Queensland Government Technical Report
This report is a scanned copy and some detail may be illegible or lost. Before acting on any information, readers are strongly advised to ensure that numerals, percentages and details are correct.
This report is intended to provide information only on the subject under review. There are limitations inherent in land resource studies, such as accuracy in relation to map scale and assumptions regarding socio-economic factors for land evaluation. Before acting on the information conveyed in this report, readers should ensure that they have received adequate professional information and advice specific to their enquiry.
While all care has been taken in the preparation of this report neither the Queensland Government nor its officers or staff accepts any responsibility for any loss or damage that may result from any inaccuracy or omission in the information contained herein.
© State of Queensland 1996
For information about this report contact [email protected] Department of Natural Resources DNRQ96001
Understanding and Managing Soils in the Stanthorpe-Rosenthal Region
Resource Information
Edited by J.M. Maher
Department of Natural Resources Brisbane 1996 w"'�*Z.,'<,!¢W%$*lr��,a:.z; NATIONAL LANDCARE
PROGRAM,. ..,...... ""··· ···· ,. ISBN 0 7242 7381 6 AGDEX 500, 510, 570
Distribution of this document is unrestricted.
1. This publication should be referenced as follows:
Maher, J.M. (ed.) 1996, Resource Information, in Understanding and Managing Soils in the Stanthorpe-Rosenthal Region, Department of Natural Resources DNRQ9600 1, Brisbane.
2. Whole publication should be referenced as follows:
Maher, J.M. (ed.) 1996, Understanding and Managing Soils in the Stanthorpe-Rosenthal Region, Department of Natural Resources DNRQ96001, Brisbane.
©The State of Queensland, Department of Natural Resources, 1996
Department of Natural Resources GPO Box 2454 Brisbane Q 4001
ii CONTENTS
List of tables v
List of figures v
List of maps VI
List of photos VI
Contributors Vl
Acknowledgments Vll
1. INTRODUCTION 1
2. CLIMATE 5 2.1 Introduction 5 2.2 Rainfall 5 2.3 Thunderstorms and hail 6 2.4 Frosts 7
. Temperature 7 '". . 2'.5· 2.6 Evaporation 8 2.7 Drought 9 2.8 Climate in relation to agriculture 10
3. GEOLOGY 13 3.1 Introduction 13 3.2 Geological history 13 3.3 Geomorphological features 14
4. LAND RESOURCES 17 4.1 Introduction 17 4.2 Land types 17 4.3 Land suitability 26 4.4 Soil properties and characteristics important to land management 29
5. VEGETATION 41
6. WATER RESOURCES 47 6.1 Introduction 47 6.2 Groundwater resources 47 6.3 Surface water resources 49 6.4 Stream and catchment management 52
iii 7. LAND USE 55 7. 1 Introduction 55 7.2 Cropping and pastures 57 7.3 Grazing 62 7.4 Horticulture 66 7.5 State Forests 68 7.6 National Parks 69 7.7 Apiculture 70
8. LAND DEGRADATION 75 8.1 Introduction 75 8.2 Loss of natural habitat 75 8.3 Soil erosion and siltation 76 8.4 Soil fertility, soil acidity and structure decline 87 8.5 Pasture rundown 89 8.6 Weed infestation and regrowth 91 8.7 Wetness 96 8.8 Salinity 97 8.9 Streambank erosion 98
9. LAND PLANNING AND MANAGEMENT - STRATEGIES FOR SUSTAINABILITY 101 9.1 Introduction 101 9.2 Farm and regional planning ' 102 9.3 Nature conservation 109
9.4 On-farm tree management j �.1 11 9.5 Horticulture 113 9.6 Pastures 115 9.7 Cultivation 120 9.8 Small holdings management 126
REFERENCES 131
APPENDIX 1 A list of plants commonly found in the Stanthorpe-Rosenthal region 133
APPENDIX2 Ratings used for interpretation of soil analyses .• 137
APPENDIX3 Analytical data for example soil profiles 139
GLOSSARY 159
iv List of tables
Table 2.1 Monthly rainfall records for selected centres in the Stanthorpe-Rosenthal region 5 Table 2.2 Hail events - Stanthorpe Post Office 6 Table 2.3 Frost frequency at various centres 6 Table 2.4 Temperatures for selected centres 7 Table 2.5 Evaporation compared with rainfall 8 Table 2.6 Occurrence of droughts at Warwick from 1865 to 1995 9 Table 2.7 Occurrence of droughts at Stanthorpe from 1873 to 1995 10
Table 4.1 Distinguishing morphological characteristics of the dominant soils 23 Table 4.2 Land use suitability for land types in the Stanthorpe-Rosenthal region 27 Table 4.3 Summary of surface soil fertility for cropping (at the sampled site) 30 Table 4.4 Important agronomic characteristics of the soils (at the sampled sites) 36
Table 5.1 Description of major vegetation types 42
Table 6.1 Summary of the groundwater resource prospects of the Stanthorpe-Rosenthal 48 region Table 6.2 Flow statistics for the Severn River and Canal Creek 50 Table 6.3 Catchment rainfall and runoff for the Severn River and Canal Creek 51
Table 7.1 Indications for cropping in Stanthorpe and Rosenthal Shires 1992-93 57 Table 7.2 Seasonal percentage of total pasture production 60 Table 7.3 State Forests within the Stanthorpe-Rosenthal region 68
Table 9.1 Land use suitability and agricultural land classes for land types in the Stan thorpe- 108 Rosenthal region Table 9.2 Recommended grasses and legumes for pasture improvement 120
List of figures
Figure 3.1 A cross-section showing the relationship between land types and geology from 15 Bony Mountain to Pozieres
Figure 6.1 Average monthly discharges for SevernRiver and Canal Creek 50
Figure 9.1 Effect of pasture ground cover on annual soil loss 116 Figure 9.2 Effect of pasture ground cover on annual runoff 116 Figure 9.3 A rainfall simulator 'rained' at Warwick at a rate of 75 mm over 45 minutes. 123 This is similar in intensity to a summer storm. Highest runoff was from the bare fallow (chisel ploughed) plot
v List of maps
following page Map 1 Locality Map 2 Map 2 Rainfall Map 6 Map 3 Catchments 48 Maps 4 & 5 Land Cover Maps 56 Map 6 Land Types inside back pocket
List of photos
Photo 7.1 Native pitted bluegrass (Bothriochloa decipiens) pastures on traprock soils, 56 Emu Park, Texas Photo 7.2 Left side of photo shows subclover and native grass pasture, Wobur 61 Photo 7.3 Vegetable production on Pozieres soil near Amiens 74 Photo 7.4 Hail netting used for storm damage control on an orchard at The Summit 74
Photo 8.1 Sheet erosion on undulating to rolling traprock hills 83 Photo 8.2 Bare patches due to salinity on flat granite plains 97
Photo 9.1 Sod seeding coated grass seed into pastures, Vermont, Warwick 119 Photo 9.2 Premier digit grass sod seeded into grassed paddock, Elbow Valley 119 Photo 9.3 An oats crop sod seeded in highly erosive creek flats,Warwick 122 Photo 9.4 Rainfall simulator, Forest Park, Warwick 123
Contributors
Emma Bryant, Resource Management, Department of Natural Resources, Toowoomba John Gray, Resource Management, Department of Natural Resources, St. George/Warwick Peter Hazelgrove, Department of Environment, Sundown National Park Ernst Heijnen, Resource Management, Department of Natural Resources, Oakey Bruce Lawrie, Conservation Strategy Branch, Department of Environment, Toowoomba Arthur Le Feuvre, Agricultural Production, Department of Primary Industries, Warwick Adrian Mackay, Water Resources, Department of Natural Resources, Warwick John Maher, Resource Management, Department of Natural Resources, Indooroopilly Ed Power, Resource Management, Department of Natural Resources, Toowoomba Geoff Sharp, Resource Management, Department of Natural Resources, Indooroopilly Ann Starasts, Agricultural Production, Department of Primary Industries, Warwick Barry Stone, Resource Management, Department of Natural Resources, Toowoomba Geoff Strom, Agricultural Production, Department of Primary Industries, Warwick Steve Tancred, formerly Agricultural Production, Department of Primary Industries, Applethorpe Bevan V anderwolf, Water Resources, Department of Natural Resources, Warwick Jo Voller, Resource Management, Department of Natural Resources, Dalby Peter Voller, Forest Service, Department of Primary Industries, Dalby Peter Warhurst, Agricultural Production, Department of Primary Industries, Warwick Bruce Wilson, South-West Regional Office, Department of Environment, Toowoomba
vi Acknowledgments
Many people have been involved with the production of this Manual. Their efforts, advice and willingness to participate are very much appreciated.
I wish to mention, in particular, Jo Voller for her considerable efforts in coordinating the regional input and chairing the core working group meetings, Diane Bray for producing the maps and Glenys Tewes for word processing. Geoff Sharp and Kathy Noble, both of the Land Management Manual Project team, made substantial contributions and are worthy of special thanks.
Mention must be made of the landholders throughout the region who freely allowed access to their properties and provided invaluable information on the local soils. Laboratory analysis of soil samples was carried out by staff of Agricultural Chemistry, Department of Natural Resources, Indooroopilly.
vii viii 1. INTRODUCTION
The Land Management Manuals Proj ect is a Department of Primary Industries 'self-help' initiative to aid decision making for sustainable land management and planning. This is achieved by increasing the awareness and aiding the understanding of land resources information within the community. The project is jointly funded by the Departments of Primary Industries and Natural Resources, and the National Landcare Program.
What is a Land Management Manual?
A Land Management Manual is a collation of currently available land resource data, combined with local knowledge and experience, primarily concerning soils and their management.
The preparation of the Manual involved a series of local workshops to obtain practical soil management information. This procedure ensured that the existing land resource information and its interpretation were up-to-date.
What area does the Manual cover?
The Manual discusses the attributes and limitations of the land types and soils used for primary production for some 462 000 hectares in the shires of Stanthorpe and that partof Warwick, previously called Rosenthal Shire.
The region includes the Granite Belt which is a popular term used to describe the large area of elevated granite between Dalveen and Wallangarra where horticulture is an important land use.
The major towns in the area are Stanthorpe, Leybum, Dalveen and Wallangarra, and the city of Warwick (which lies just outside the Manual area boundary).
The project area and its relationship to Manuals in surroundingregions are shown in Map 1.
1 Introduction
Why have a Land Management Manual?
Running a successful rural enterprise, over a long period of time, is dependent on the correct use of the available resources. Decision making should be determined by the ability of the resource to produce - not on historical practices which in some cases have led to resource degradation.
This Manual is designed to increase the awareness of the capabilities of the land types and soils within the region, and in so doing, minimise potential land degradation. It brings together the currently available resource data and practical management information in a format which is easy to use and understand.
The Manual provides a handy tool for users to identify and evaluate their land types and soils. The consideration of soils information is essential when developing long-term strategies for property management or for local planning.
What does the Manual contain?
The Land Management Manual package has three major parts contained within a ring -binder.
• The Field Manual: the core and most important component of the package. It provides a summary of the region's soil and land characteristics, and provides recommendations for appropriate management and use. This section of the Manual also provides information on identifying the soils. Various visual aids are provided for this purpose, including maps, tables, land type sheets and landscape and soil photographs. Farmers and graziers will find the land type sheets that contain land use and management information for their soils particularly useful. An increased knowledge of soils and their behaviour helps decision making on optimising production on different soils while minimising land degradation.
• The Resource Information: a reference document that provides a regional overview and places the soils information within this context. To support the information contained in the Field Manual, this document explains local land resource-related aspects in more detail. Land use problems encountered from local experience, and the solutions implemented are also dealt with.
2 SOUTH N A CENTRAL PACIFIC
DOWNS
(
I :: � ) 7 \ I
\_ 'i
NEW
SOUTH � I r (
� ( '\___ LOCALITY MAP \
REGION Scale 1 : 550 000
DOWNS 0 10 20 km 1,' NATU4RAL RESOURCES Map 1 Introduction
Who should use the Manual?
The Manual is a concise source of information for landholders, Departmental extension officers and groups or persons involved in farm planning (e.g. Landcare groups and Property Management Planning groups).
The following list illustrates the range of potential users of the Manual. Although the list only gives one example per user, the range of possible uses is more extensive.
Present landholders - to re-assess the potential of their property New landholders - to assess the realistic potential of their property Potential landholders - to assess the realistic potential of a property Property Management - for resource-based property planning Planning (PMP) groups Landcare groups - for resource-based planning over large areas Planners/consultants - to assess property and land potential Extension staff - for sound advice on property potential Educators - for education on soils and their sound use Land valuers - for property potential and valuation Rural banks - for informed decision making Local authorities - for shire development plans Dept. of Transport - for better road construction and erosion control Queensland Rail - for erosion control SWQEB - for erosion control on line construction Telecom - for erosion control on line installation.
3 4 2. CLIMATE
Ed Power
2.1 Introduction
The climate of the Stanthorpe-Rosenthal region is classified as moist sub-humid in the Granite Belt and dry sub-humid in areas of lower elevation. The climate of the region is predominantly influenced by both tropical and temperate weather patterns. The region is also influencedby continental and maritime climate patterns. Erratic summer storms, heavy winter frosts and droughts are also features of the region's climate.
2.2 Rainfall
The region's rainfall is summer dominant with 62 to 65 percent of mean annual rainfall falling between October and March with heaviest rainfall from December to February. Early summer rains are usually generated by storm activity with heavy intensity rainfall and sometimes heavy localised hail.
Table 2.1 Monthly rainfa ll records fo r selected centres in the Stanthorpe-Rosenthal region
Centre Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec YEAR
Warwick 92 78 65 40 40 41 44 35 41 64 69 91 701 Leyburn 88 73 56 40 40 40 43 31 40 62 68 87 669 Piked ale 91 73 58 37 42 47 45 40 46 66 73 88 706 Dalveen 111 98 81 53 56 59 59 45 53 72 79 106 873 Applethorpe 104 82 72 51 57 39 49 51 51 74 80 89 810 Stanthorpe 97 86 67 44 46 47 50 43 52 69 73 93 770 Wallangarra 103 84 68 40 45 49 54 42 49 75 78 99 785 Riverton N 95 81 56 36 49 36 45 41 46 72 69 84 704 Texas 87 75 57 36 40 41 43 35 40 60 64 79 657 Warroo 79 72 52 38 38 42 42 34 39 60 66 86 648 Sour ce: Bur eau of Meteor olog y
Higher annual rainfall occurs on the Granite Belt compared to areas to the north and west (see Map 2). Dalveen at an elevation of 826 metres receives a mean annual rainfall of 873 mm and Stanthorpe at 792 metres receives 770 mm, compared with 701 mm at Warwick which has an elevation of 477 metres above sea-level. Both Stanthorpe and Dalveen average 18-20 more raindays annually than Warwick's 79 raindays. Rainfall decreases in intensity from east to west across the region.
5 Climate
2.3 Thunderstorms and hail
Thunderstorms may form when cold fronts move through the region. They also may form over the Border Ranges to the east, or form locally as a result of intense daytime temperatures associated with humid summer conditions. Stanthorpe is reported as experiencing 50 to 60 thunderstorms per year and Warwick 40 thunderstorms. Early summer rainfall is usually generated by storm activity.
Hail is often associated with thunderstorms in the region, particularly from October to January. Hail events are localised but often severe, causing extensive damage particularly to stone fruit crops. Stanthorpe Post Office is the only centre in the region where hail is officially recorded. Therefore it is difficult to assess the intensity, frequency and duration of hail events over the region. Information from press reports and anecdotal reports suggest that hail storms are more frequent in the Granite Belt than in areas to the east and west. Hail storms have the severest economic impact in horticultural areas of the Granite Belt.
Table 2.2 Hail events - Stanthorpe Post Offi ce
Month Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Total
No. of yrs 30 30 30 29 29 30 30 31 29 30 28 28 28 Total 6 1 1 0 0 1 1 3 3 6 10 6 37 ev en ts Mean 0.20 0.03 0.03 0 0 0.03 0.03 0.10 0.11 0.20 0.36 0.21 1.32
Sour ce: Bur eau of Meteor olog y
Table 2.3 Frost frequency at various centres
Number of frost occurrences
Centre Warwick Applethorpe Stanthorpe Wallangarra
Mon th Lig ht Heav y Lig ht Heav y Lig ht Heav y Lig ht Heav y <2.2'C Sour ce: Bur eau of Meteor olog y 6 750 eo0 / -...._, -' ; ..f ) I h� I ( � l NEW SOUTH' WALES STANTHORPE-ROSENTHAL REGION RAINFALL MAP LEGEND Scale 1 : 550 000 Stanthorpe-Rosenthal Region ______--- 0 10 20 km �------� Mean Annual Rainfalllsohyet (mm)--- .. --?so.._____ NATURAL RESOURCES Map2 Climate 2.4 Frosts Frosts are an important climatic factor in theregion. Low winter temperatures are important for the development of 'low chill' horticultural crops. The occurrence and severity of frost influences farming strategies throughout the area. Table 2.3 lists frost occurrences for Warwick, Applethorpe, Stan thorpe and W allangarra. Early frosts usually indicate that there will be late frosts that year. The higher incidence of frost and extended duration of the frost season on the Granite Belt means that frost has a heavier impact on production of horticultural crops. 2.5 Temperature Temperatures recorded in the area are frequently the coolest in Queensland. Elevation has a marked influence on temperature. Wallangarra, at an elevation of 877 metres, has the lowest mean winter and summer temperatures, slightly lower than Applethorpe at 870 metres elevation and Stanthorpe at 792 metres elevation. Warwick at 477 metres elevation has higher summer and winter temperatures than Granite Belt centres. Table 2.4 Temperatures fo r selected centres Centre Warwick Stanthorpe Applethorpe Wallangarra (477 metres (792 metres (870 metres (877 metres elevation) elevation) elevation) elevation) Month Min. °C Max. °C Min. °C Max. °C Min. °C Max. °C Min. °C Max. °C Jan 17.3 29.7 15.5 26.9 15.1 25.9 14.8 26.5 Feb 17.1 28.8 15.5 26.4 14.9 24.8 14.7 25.5 Mar 15.5 27.6 13.8 24.9 13.4 23.6 12.9 24.3 Apr 11.5 24.9 9.6 22.2 9.6 20.9 9.1 21.4 May 8.2 20.6 5.3 18.1 6.5 16.9 5.9 17.5 Jun 4.6 18.0 2.4 15.4 3.0 14.2 3.0 14.3 Jul 3.1 17.3 0.8 14.5 1.7 13.5 1.9 13.7 Aug 4.2 18.9 2.1 16.0 2.9 14.9 3.0 15.3 Sept 7.0 21 .9 5.1 19.0 5.5 18.1 5.5 18.0 Oct 10.8 24.8 8.9 22.1 9.0 21 .2 8.5 21.1 Nov 13.5 27.5 11.8 25.0 11.3 23.2 11.1 23.8 Dec 15.8 29.5 14.1 26.8 13.6 25.6 13.2 26.2 Sour ce: Bur eau of Meteor olog y 7 Climate Heatwave conditions may be experienced in Warwick and other centres of lower elevation in the region. Warwick can expect two days in January where the temperature exceeds 35°C and sixteen days where the temperature exceeds 30°C. Areas in the Granite Belt generally do not experience summer heatwaves. 2. 6 Evaporation The mean daily and monthly evaporation rates in comparison to monthly rainfall are given for Warwick and Stanthorpe in Table 2.5. Table 2.5 Evaporation compared with rainfall Centre Warwick Stanthorpe Evaporation Evaporation Daily Monthly Rainfall Daily Monthly Rainfall (mm) (mm) Monthly (mm) (mm) Monthly (mm) (mm) Jan 7.0 217 92 5.9 183 97 Feb 5.7 160 78 5.1 143 86 Mar 4.8 149 65 4.2 130 67 Apr 4.0 120 40 3.4 102 44 May 2.8 87 40 2.5 78 46 Jun 2.6 78 41 2.3 69 47 Jul 2.8 87 44 2.5 78 50 Aug 3.5 109 35 2.9 90 43 Sept 4.4 132 41 3.8 114 52 Oct 5.3 164 64 4.5 140 69 Nov 6.4 192 69 5.9 177 73 Dec 7.6 236 91 6.4 198 93 An n ual 4.7 1731 701 4.1 1502 770 Sour ce: Bur eau of Meteor olog y The average evaporation rates exceed the average rainfall for every month of the year. The soil water deficit for the summer months combined with low moisture holding capacity of many soils in the area makes dryland summer cropping unreliable. As theevaporation rate for these centres is approximately twice their annual rainfall, management practices which reduce run-off, increase infiltration and reduce evaporation are important. Practices such as stubble retention and fallowing are practical ways to retain soil moisture for cropping. Horticultural crops are increasingly reliant on trickle irrigation to overcome the moisture deficit. 8 Climate 2.7 Drought Droughts are a regular feature of theregi on's climate. Droughts are defined here as severe rainfall deficiencies over a period of at least twelve months. A severe drought has less rainfall than that received in the driestfi ve percent of calendar years at that location; a moderate drought receives rainfall in the range between the driest five and ten percent of years. Droughts are recorded for 130 years at Warwick in Table 2.6. A more detailed breakdown of droughts can be obtained from Australian Rainman (Clewett et al. 1994). Table 2.6 Occurrence of droughts at Warwickfrom 1865 to 1995 Period Duration Total rain %of time in (months) (mm) severe drought Jan 1865 to Nov 1866 23 833 92 May 1871 toAug 1872 16 558 80 Mar 1878 toFeb 1879 12 472 0 Feb 1883 to Nov 1885 34 1359 26 Aug 1887 toMar 1889 20 906 44 Aug 1901 toApr 1903 21 925 50 Feb 1911 toMay 1912 16 597 20 Apr 1914 to Dec 1915 21 858 30 Jan 1918 toJun 1920 30 1198 42 Jan 1923 to Dec 1923 12 457 0 Sep 1925 toSep 1927 25 975 14 May 1929 toApr 1930 12 444 100 Nov 1935 to Oct 1936 12 478 0 Jan 1941 toJan 1942 13 534 50 Feb 1951 toFeb 1952 13 458 50 Jun 1953 toMay 1954 12 473 0 Jan 1957 to Nov 1958 23 827 83 Jul1964 toJun 1965 12 482 0 Oct 1971 toSep 1972 12 504 0 Dec 1979 to Jun 1981 19 824 0 Jun 1990 to Nov 1991 18 539 86 May 1992 toApr 1995 36 1480 28 9 Climate Table 2.7 Occurrence of droughts at Stanthorpe from 1873 to 1995 Period Duration Total rain %of time in (months) (mm) severe drought Feb 1874 toJan 1875 12 497 0 May 1875 toJan 1878 33 1373 41 Mar 1883 toJul 1885 29 1176 56 Sep 1887 toMar 1889 19 943 38 Apr 1898 to Mar 1899 12 550 0 May 1901 toJun 1903 26 1148 67 Apr 1908 to Mar 1909 12 576 0 Mar 1911 toMay 1912 15 628 25 Apr 1914 toJan 1916 22 1010 45 Jan 1918 toJul 1920 31 1299 55 Dec 1922 toJan 1924 14 748 33 Aug 1925 toFeb 1927 19 996 38 Mar 1935 toOct 1936 20 815 11 Mar 1938 to Feb 1939 12 543 0 Sep 1939 toMay 1941 21 1066 0 Feb 1944 toJan 1945 12 526 0 Sep 1945 toAug 1946 12 546 0 Nov 1952 toJan 1954 15 564 75 Jul 1956 to Sep 1958 27 1205 56 May 1964 toNov 1965 19 876 25 Dec19 79 toJan 1981 14 618 33 Jul 1990 to Sep 1991 15 637 0 Jun 1992 toOct 1994 29 1292 11 Source: Australian Rain man Examination of annual rainfall records for Stanthorpe for the 122 years from 1873 to 1995 shows that there have been 23 droughts and that these droughts cover similar years to those recorded for Warwick, but do not precisely match reflecting climate differences between these two centres. Examination of the above tables shows that there is no such thing as a "normal" year. Droughts are a recurring feature of the region's climate. 2.8 Climate in relation to agriculture It is the cold winters and cool summers that make horticulture economically feasible on the Granite Belt, despite the soils being less suitable for horticultural crops than most traditional fruit and vegetable growing areas. These mild, temperate conditions are due to the elevation of 800 to 940 metres above sea level. Stanthorpe experiences an average of 50 heavy frosts annually and over 70 frosts per year, which satisfies the winter chilling requirements of deciduous tree 10 Climate crops. Insufficient chilling hours leads to reduced flowering. Stop/start winters are also detrimental to the flowering and development of stone fruit. Frost in mid to late autumn and early spring limits the planting and harvesting of frost sensitive vegetables, and for this reason site selection is important. Spring frosts can also damage the young shoots, flowers and fruitlets of trees and vines. Variety and planting selection are very important, especially with stone fruit, as many new varieties flower early in spring. The risk of late frosts has limited the planting of trees and vines in low lying areas and immediately beside the major watercourses of the SevernRiver, The Broadwater, and Cannon and Accommodation creeks. Temperatures are mild on the Granite Belt during the October to April growing season, ranging from average monthly minimums of 9-l5°C to maximums of 22-27°C, which suit most vegetable crops. Heatwaves areuncommon and cool nights are usual. Excessively hot, humid or wet weather conditions, which often occur in coastal horticultural districts at this time, can advantage Granite Belt vegetable producers as market shortages increase demand and prices. Stanthorpe's rainfall averages 769 mm with 485 mm (63%) falling in the growing season. This is adequate for dryland horticulture, but most modern intensive production systems are based on irrigation to overcome short-term deficits and provide for longer term droughts. Most fruit trees, vines and many vegetables (tomatoes, capsicums, cucurbits) are grown under trickle irrigation as it is more efficient than overhead spraying. However, some tree crops have overhead irrigation to prevent damage from late frosts. There is local variation in the rainfall, with Dalveen in the north receiving an average of 873 mm, Ballandean in the south receiving 760 mm, Amiens in the west receiving 775 mm and Eukey in the east receiving 825 mm. The northern and eastern areas of the Granite Belt are closer to the eastern downfall of the Great Dividing Range and this extra rainfall occurs mainly as drizzle accompanied with mist from the east. Hence, these areas are less suited to crops like grapes, some stone fruit and many vegetables which are prone to fungal or bacterial diseases. In fact, it is this easterly influence that has limited development of orchards on some areas with suitable horticultural soils to the east of the NSW/Queensland border. Frost occurrence influences the selection of barley and wheat varieties, and the planting time of these crops, which are mainly grown in the region's north. Winter crops are usually planted in May or June to avoid frost damage to flowering crops. Late seasonal frosts are uncommon in grain growing areas and do not usually affect production. However, strong winds around 65 kmlhour can cause crop damage and lodging. The grain filling stage of wheat, from September onwards, requires an optimal monthly rainfall of 70 mm, which is higher than the mean rainfall for Warwick for those months. Very cold weather poses the most direct threat to livestock, particularly if accompanied by wind. Sheep are most at risk if cold snaps occur during lambing or during shearing in early spring. Drought affects beef cattle and sheep 11 Climate production as their major food source is native pasture forage. Dairying in the region is also adversely affected by low rainfall and to a lesser extent by low temperatures. Further Reading Cassidy, G.J. (ed.) 1988, Land Management Manual - Shire of Inglewood, Inglewood Shire Bicentennial Land Management Committee. Marshall, J.P., Crothers, R.B., Macnish, S.E. and Mullins, J.A. 1988, Land Management Field Manual - South-east Darling Downs District, Department of Primary Industries Training Series QE88001, Queensland. Wills, A.K. 1976, The Granite and Traprock Area of South East Queensland, Division of Land Utilisation, Technical Bulletin No.l3, Queensland Department of Primary Industries. 12 3. GEOLOGY Emma Bryant 3.1 Introduction An understanding of the geology and geomorphology in an area is necessary to understand the characteristics of the rest of the landscape, such as landform, soils, vegetation and land capability. The geology of the area has been mapped and interpreted by the Geological Survey of Queensland on the Goondiwindi and Warwick 1 :250 000 map sheets. It was well summarised in the Granite and Traprock report (Wills 1974) which was used as a basis for this chapter. 3.2 Geological history There are four major geological divisions in the Manual area; traprock, granite intrusions, sandstone and alluvium. The traprock is the oldest rock formation in the area, with the oldest rocks occurring south of Warwick near Mount Silverwood. Traprock is a popular term used to describe a complex mixture of highly deformed sandstone and mudstone, interbedded conglomerate, limestone and volcanics. It ranges in age from Ordovician to Permian times (approximately 450 to 250 million years ago) and forms the northern border of the New England Fold Belt. The granitic rocks are the next oldest rocks, having intruded through the traprock during Permian to Lower Triassic times (approximately 250 to 200 million years ago). These intrusions caused the whole Fold Belt to be uplifted. The traprock and granite together make up more than three quarters of the study area. Sandstone and mudstone sediments are located to the north and north-east of the Fold Belt, mainly near Warwick and Ley burn. These sediments are a result of erosion and deposition from the uplifted traprock and granite. The initial deposition formed coarse grained sediments known commonly as Marburg Sandstone. As deposition slowed, swamps and lakesfor med within the sandstone which then filled with sediments forming the sedimentary rock known as the Walloon Coal Measures. During the Cretaceous and early Tertiary times (approximately 130 to 50 million years ago) minor faulting and folding of rocks occurred and volcanic extrusions formed the Main Range Volcanics which are present to the north and east of the Manual area. Widespread erosion of the outcropping rocks produced the alluvial deposits along the creeks and rivers. 13 Geology 3.3 Geomorphological features Each of the four major geological types displays a set of distinct landform features. The traprock is characterised by a series of hard ridges which are a result of folding of the bedrock. Some of these ridges form the highest parts of the landscape and usually surround a granite intrusion, for example near Leslie Dam. The heat and force of the granite intrusion into the traprock resulted in the traprock being metamorphosed into a harder rock which is very resistant to erosion. Hence, it stands above the rest of the landscape. Other less resistant traprock generally occurs at the same elevation or lower than the granite. Other distinctive features of the traprock areincised rivers and gorges such as the Severn Gorge. Again, the hardness of the traprock has prevented any wide river beds from forming. The granite, often referred to as the Granite Belt in this region,has a very complex surface ranging from very rocky mountains to gentle non-rocky basins. This variable land surface is the result of a number of different types of granite rock and varying erosion resistance. However, the granite is most commonly in high parts of the landscape because of its relatively high resistance to erosion. The most obvious features of the granite are the tors or boulders and the massive granite rock hills. Girraween National Park has many good examples of these and other features, such as exposed rock platforms and balancing rocks. There are four types of granite in the Manual area. Ruby Creek Granite is generally the most resistant to erosion and has produced the rugged ridges around the Broadwater Basin and The Summitpla teau. The most widespread granite, Stanthorpe Adamellite, has a more variable landscape depending on erosion patterns, varying from the very rocky, mountainous Girraween area to the low relief SevernleaBa sin, west of Stanthorpe. The Herries Adamellite occurs to the north of the main Granite Belt. It has eroded to form a gentle basin surrounded by metamorphosed traprock which drains into Leslie Dam. Sandstone caps still exist on some of these ridges. The Greymare Granodiorite, west of Warwick, has eroded away to a very gentle basin surrounded by metamorphosed traprock hills. The sandstone has a relatively gentle topography compared to the traprock and granite. The softer rock is gradually being eroded and grades gently into the alluvial floodplains. A cross-section showing the relationship between land types and the parent rocks on which they have developed in the Bony Mountain to Pozieres area, is shown in Figure 3.1. 14 Geology I 1 SR : u: MBAP UTRTH GRUS ULSH GR UTRTH LTH GH : s: : Tcs : I l R I I 1000 m 800 m 600 m 400 m 200m O Sandstone Alluvium SR Sandstone Ridges USR Undulating Sandstone Rises MBAP Mixed Basalt Alluvial Plains UTRTH Undulating to Rolling Traprock Hills GRUS Granite Rises-Unform Sands ULSH Undulating Low Sandstone Hills GRTCS Granite Rises-Texture Contrast Soils LTH Low Traprock Hills GH - Granite Hills EGP - Elevated Granite Plains Figure 3.1 A cross-section showing the relationship between land types and geology from Bony Mountain to Pozieres. 15 16 4. LAND RESOURCES Emma Bryant and John Maher 4.1 Introduction Understanding the land resources of an area is essential to understanding the land management practices required of that area. Each land type described in this section is a mapping unit based on a particular type of geology and landform, and will generally have a typical pattern of soils and vegetation types. There are 21 land types in the Manual area; five in the traprock, eight in the granite, five in the sandstone and three in the alluvium. The distinguishing morphological characteristics of the dominant soils occurring in the land types are given in Table 4.1. 4.2 Land types 4.2.1 Land types develop ed on the alluvium Three types of alluvial plains occur in the Manual area. Those developed on predominantly basalt derived deposits, those on a mixture of granite and traprock deposits and those on a mixture of traprock and sandstone deposits. Mixed basalt alluvial plains: The broad floodplain of the Condamine River occurs in the very north of the study area, covering <1% of the total area. It is mixed alluvium with a large proportion being derived from the basalt slopes east of the manual area. The slope of the plain is very gentle, 0-2%, and it is generally 1-2 km wide. The soils on this floodplain, called Pratten, are mainly deep, dark cracking clays that have a self mulching surface and alkaline subsoil. Granite/traprock alluvial plains: This is not a very common unit in the Manual area, <1 %, occurring only along minor creeks that run into the Condamine River off the northern slopes of the traprock, e.g. Rodgers Creek. The alluvium is mostly derived from traprock and granite and its common slope is generally 0-1%. The dominant soils, called Rodger, are deep, texture contrast soils with a massive, very dark greyish brown topsoil that is hard setting, a bleached subsurface layer and a very dark grey to dark greyish brown alkaline clay subsoil. 17 LandResources Traprock/sandstone alluvial plains (traprock major creek flats): These plains are found in the north of the Manual area around Ley burn, along creeks such as Canal and Thane creeks and occasionally along creeks throughout the traprock. They cover only 2% of the Manual area. These creek flats are developed from material that has washed down from the traprock and sandstone hills. The slope of these creek flats ranges between 0-4% and their width between 200 m and 2 km. The dominant soil found is called Leyburn which is a moderately deep to deep texture contrast soil witha massive, hard setting, gravelly topsoil, a bleached subsurface layer and a yellowish brown or mottled brown neutral to alkaline clay subsoil. 4.2.2 Land typ es developed on the granite The granite land types range from very rocky and mountainous to gently undulating non-rocky valleys and plateaus. There are three main soils in the granite; Banca, Pozieres and Cottonvale. In general, Banca soils occur in the rocky, mountainous areas, Pozieres in the less rocky areas and Cotton vale in the lower, gentle, non-rocky valleys. Rolling granite mountains: These occur in the southernpart of the Granite Belt as the Girraween National Park and Jibbinbar Mountain. They cover approximately 5% of the Manual area. They are highly dissected with slopes commonly 30%, and tors and boulders are very common. The dominant soil, Banca, has formed between the granite tors as a result of slow erosion of the rock. It is a uniform sand of variable depth (25-90 em) but usually shallow. Very dark grey to brown sandy topsoils overlie a bleached sand which is underlain by either more sand, a hardpan or rock. Small pockets witha yellow clay subsoil may also occur as a minor soil. Granite hills: This land type is less dissected than the 'rolling granite mountains' with side slopes averaging 10-15%. The Granite hills occur throughout the Manual area, covering approximately 8%, as either rolling hills, as near Mount Magnus, as narrow ridges or spurs, as in the basin of the upper SevernRiver, or as isolated rocky knolls around The Summit. The most common soil in this land type is also Banca, with a minor occurrence of texture contrast soils with a yellow clay subsoil and sandy topsoil. Undulating low granite hills: Undulating low granite hills have gentle relief, side slopes ranging between 5-12% and common rock outcrop. It is an uncommon land type, covering <1% of the Manual area. It occurs in isolated areas in the traprock, for example in the Greymare granite basin west of Warwick and in an area west of Pikedale. The dominant soil in this land type is Banca, as in the previous units, with again small pockets of texture contrast soils with yellow clay subsoils. 18 LandResources Granite rises - uniform sands: These rises are distinguished from the previous granite land types by being mainly lower in the landscape, more gently sloping (average slopes 2-9%) and less rocky. They occur in valleys, including small isolated valleys in very mountainous areas such as Girraween, and in very gently sloping elevated areas. They have been formed as a result of sand being eroded and carried downslope from the rockier, higher areas. Where these rises occur near Leslie Dam, they can have residual sandstone caps. These rises cover approximately 8% of the Manual area. The most common soil found on these gentle rises and slopes is Pozieres. The Pozieres soil is very similar to Banca in that it is a uniform sandy soil with a dark greyish brown to very dark grey topsoil and a bleached subsurface layer overlying a hardpan or hard rock. The main difference between the two soils is that Pozieres is more likely to be deeper, usually greater than 60 em, due to a lower amount of rock outcrop. The Pozieres soils are, as a consequence, used more for horticultural purposes than the Banca soils. The minor soil associated with this unit is a texture contrast soil with a yellow and grey subsoil. Elevated granite plains: This elevated granite plain, which occurs in the Cottonvale - The Summit area, has average slopes of 2-4%, is generally non-rocky, and covers 2% of the Manual area. The dominant soil in this land type is the deep Cottonvale soil. This soil is a deep texture contrast soil with a very dark grey to dark brown sandy topsoil overlying a bleached layer and then a mottled brown, grey or yellowish grey acidic clay subsoil. The mottling indicates that drainage is poor. The Pozieres soils can also occur in this landscape. Undulating granite plains: This land type occurs in lower colluvial valleys, such as the one to the west of Stanthorpe. It covers approximately 12% of the area. These plains have gently undulating topography, with slopes 0-3% along the valley floors and 3-9% on the adj acent colluvial slopes. They have low relief and are generally non-rocky. The major soil found in this land type is the texture contrast Cottonvale soil found in the previous land type. The most common minor soil is Pozieres. Granite rises - texture contrast soils: These gently undulating rises occur as eroded granite basins between thetraprock and granite hills. They occur south of Ballandean, east of Montrose and scattered in the granite hills between Leslie Dam and Mount Magnus. They cover approximately 3% of the Manual area. The slopes of these rises are 1-6% and the soil most commonly found is Greymare. The Greymare soils are texture contrast soils with very dark grey to dark brown sandy topsoils overlying a bleached layer and then a mottled pale yellow to greyish yellow-brown clay. They are usually moderately deep to deep, acid to neutral, poorly structured and poorly drained. 19 LandResources Flat granite plains: These plains most commonly occur in association with the previous 'granite rises - texture contrast soils' land type, as around Ballandean. They are found in granite basins and along drainage lines, and cover <1% of the Manual area. Slopes average 0-3%. The soils, called Lyra, are very similar to the Greymare soils described above; the maj or difference being that they have alkaline subsoils rather than acid. They are texture contrast soils with light yellowish brown, poorly structured clay subsoils, a bleached subsurface layer and sandy topsoils. 4.2.3 Land typ es develop ed on the sandstone The land types in the sandstone range from rocky ridges with shallow soils, to undulating rises with deep soils that are suitable for limited cropping. Sandstone ridges: These isolated remnants of Jurassic (Marburg) sediments occur in the north of the area around Leybum and Bony Mountain. They cover <1% of the Manual area. Because they have been hardened and ferruginised (impregnated with iron) in the past, they resisted complete weathering and erosion. The slopes in this land type range between 0 and 15% on the ridges and up to 100% on the scarp slopes, more commonly known as jumpups. The most common soil in this land type is Hanmer which is a shallow to moderately deep texture contrast soil. It has a gravelly, massive, hard setting dark brown topsoil which lies over a bleached layer and then a reddish brown to grey, acid, mottled clay subsoil. A minor soil found in this land type is a shallow, stony sand. Undulating low sandstone hills: These undulating Marburg sandstone hills are restricted in location to an area south-west of Warwick. They cover approximately 2% of the Manual area. The side slopes of these hills range between 2-10% and the 'sandstone ridges', described previously, occasionally outcrop within them. Two soils commonly occur; Dalveen and Mardon. The Dalveen soil is a moderately deep to deep soil (60-90 em deep) with a gravelly, hard setting dark brown topsoil overlying a thick bleached layer and a brown to yellowish brown, mottled, acid to neutral clay subsoil. The Mardon soil is similar to the Dalveen, the main difference being that it gradually increases in clay content with depth rather than being an abrupt change as in a texture contrast soil. It is moderately deep to deep, has a gravelly dark reddish brown to dark brown topsoil which grades into a massive dark reddish brown to brown, acid to neutral sandy clay subsoil. Undulating sandstone rises: These undulating Marburg sediments occur to the west of Warwick along the Condamine River. They cover approximately 1% of the Manual area. Slopes of this land type are usually between 2-6%, with down to 0% near the valleys. The most common soil is Allan which is a deep texture contrast soil. It has a dark brown to dark yellowish brown sandy topsoil which occasionally overlies a bleached layer and a brown to yellowish brown, neutral to alkaline clay subsoil. 20 LandResources The subsoil often has a coarse blocky structure and contains manganese and/or carbonate concretions. Gently undulating sandy rises: These Marburg sandy rises mostly occur in large patches on the northern edge of the traprock near creek lines around Leyburn. They cover approximately 2% of the Manual area and 'sandstone ridges' often outcrop within them. Slopes range between 1-3% and the two dominant soils coincide with the different types of sandstone beds. Bonnie Doon is a gravelly, moderately deep to deep, texture contrast soil. It has a dark brown to grey sandy loam topsoil over a deep, gravelly bleached layer and a mottled greyish brown to brown, acid clay subsoil. The Drome soil is a deep, bleached siliceous sand which becomes increasingly yellow with depth from a brownish surface. Gently undulating sandstone plains: These sandstone plains, with slopes 1-3%, occur in association with the previous land type around Leyburn. They cover approximately 1% of the Manual area. The dominant soil is Maxland which is a moderately deep to deep texture contrast soil. It has a gravelly, hard setting dark brown to greyish brown sandy topsoil over a bleached, gravelly layer which overlies a frequently mottled, greyish brown to yellowish brown, coarse blocky, neutral to alkaline clay subsoil. The subsoil is often high in sodium and salt, and waterlogging and low fertility are common. The Bonnie Doon soil can also occur on these plains. 4.2.4 Land typ es develop ed on the traprock Land types within the traprock range from intensely dissected mountains to plains along the valley floors. However, regardless of this variation in land type, the traprock area is dominated by two soils; Gammie and Karangi. Traprock mountains: These intensely dissected mountains have slopes up to vertical, and sharp, narrow ridges. They occur south of the granite belt along the border around the deeply dissected SevernRiver, in the Sundown National Park, and south of Girraween National Park, and cover <1% of the Manual area. Two soils occur in this land type. The Gammie soil is a very shallow to shallow (20-30 em) gravelly loam to clay loam with a massive dark brown to brown topsoil overlying a bleached acid subsurface which overlies weathered rock. Occasionally, this subsoil deepens to encounter a weakly structured, yellowish brown, brown or reddish brown acid clay. This shallow to moderately deep (35-70 em) soil profile is then called the Karangi soil. The Karangi soil tends to occur in the lower, gentler parts of the landscape where soil formation is greater. Generally, both the Karangi and Gammie soils are unproductive and prone to sheet erosion. Undulating to rolling traprock hills: These traprock hills run through the area from the border south of Glenlyon, along the western edge of the granite belt up to and around Leslie Dam and Ley bum. 21 LandResources Consequently, they are a common land type and cover approximately 36% of the Manual area. They have a typical slope of 20%, ranging between 10 and 30%. Along some down-cutting creeks, such as Pike Creek, slopes can reach 60%. The undulating hills in the Pikedale area have average slopes of 10%. The hills occur mainly as ridges which run in a NW-SE to a N-S direction. North of Braeside and south of Greyrnare they occur as metamorphic aureoles around granite basins. The soils that occur in this land type are the same as the previous land type; Gammie and Karangi. Surfaces are often stony and there are occasional rock outcrops. Low traprock hills: Undulating low traprock hills are less common in the study area, covering approximately 7% of the Manual area. They generally occur lower in the traprock landscape, in valleys surrounding watercourses. Slopes are mainly 4-6% and relief is gentle. Isolated traprock knolls are also included in this land type. They have a similar landform to the low hills; slopes of 5% and gentle relief, but outcrop through the sedimentary rock in the north near the Condarnine River. The ground surface in this land type is usually stony, and again the most common soils are Gammie and Karangi as in previous traprock land types. The Karangi soil is perhaps more common in this than in the steeper land types, as it is found more frequently on gentle slopes. It is also often slightly deeper because of the gentle topography. Traprock plains: These low footslopes and colluvial slopes found along drainage lines throughout the traprock hills have typical slopes of 1-6% and low relief. They mainly occur in theThane to Karara area and cover approximately 7% of the Manual area. The most common soil within this land type is Karangi; the gravelly texture contrast soil that occurs in previously described traprock land types. In this land type, however, it has a much deeper profile (approximately 80 ern) due to it being low in the landscape. Elevated low traprock hills: To the west of Dalveen and south-west of Morgan Park lie two small areas of traprock hills with an associated soil called Glentanna. They cover <1% of the Manual area. These undulating hills have an average slope of 3-10% and generally have stony surfaces. The Glentanna soil is a shallow to moderately deep texture contrast soil with a gravelly, friable, dark brown or brown loam to clay loam topsoil over an occasionally bleached subsurface layer and a brown to reddish brown acid to neutral clay subsoil. It tends to set hard easily. This land type is very erodible and often has rock outcrops, but is one of the most productive on the traprock. 22 Table 4.1 Distinguishing morphological characteristics of the dominant soils SOIL COLOUR TEXTURE STRUCTURE OTHER PROFILE CHARACTERISTICS Allan surface soil dark brown to dark yellowish sandy clay loam to loamy sand massive, may be blocky neutral pH, may have a subsurface bleach brown upper subsoil yellowish brown to brown fine sandy medium clay strong blocky contains manganese, neutral pH lower subsoil brownish yellow clay loam coarse sandy weak blocky manganese and calcareous soft segregations, very strongly alkaline Banca surface soil very dark grey to brown loamy coarse sand loose gritty, may have a bleached subsurface, slightly acid upper subsoil brown clayey coarse sand massive slightly acid lower subsoil brown coarse sand massive hardpan, slightly to medium acid Bonnie Doon surface soil dark brown to very dark grey sandy loam massive hard setting, slightly acid, bleached subsurface upper subsoil greyish brown to brown coarse sandy light medium clay moderate blocky mottled, strongly acid lower subsoil light greyish brown coarse sandy medium clay weak blocky mottled, some quartz, strongly acid Cottonvale surface soil dark brown to very dark grey coarse sandy clay loam moderate granular to bleached subsurface, medium to slightly acid massive upper subsoil brown, grey or yellowish grey coarse sandy light clay moderate blocky mottled, extremely acid lower subsoil grey coarse sandy light clay massive mottled, very strongly acid Dalveen surface soil dark brown sandy clay loam to sandy loam weak granular to massive loose to hard setting, bleached subsurface, slightly acid to neutral, gravelly upper subsoil brown to yellowish brown medium clay weak blocky mottled, slightly acid to neutral lower subsoil yellowish brown coarse sandy medium clay weak blocky mottled, slightly acid to neutral Drome surface soil brown to light brownish grey sandy loam to loamy sand weak granular may be bleached, medium acid upper subsoil brownish yellow loamy sand to sand single grain slightly acid lower subsoil brownish yellow sandy loam single grain mottled, neutral pH N CN N .j::a. SOIL COLOUR TEXTURE STRUCTURE OTHER PROFILE CHARACTERISTICS Gammie surface soil dark brown to brown clay loam massive coarse fragments and gravel, may have bleached subsurface, neutral pH upper subsoil brown to yellowish brown clay loam massive gravel and weathered rock, neutral to mildly alkaline Glentanna surface soil dark brown to brown sandy clay loam weak blocky to massive abundant coarse gravel, hard setting, slightly acid, may have bleached subsurface upper subsoil brown to reddish brown light medium clay strong blocky slightly gravelly, mildly alkaline lower subsoil brown medium clay strong blocky slightly gravelly, mildly alkaline Greymare surface soil very dark greyish brown coarse sandy clay loam to massive to granular usually hard setting, bleached subsurfa ce, neutral pH sandy loam upper subsoil pale yellow to greyish yellow- coarse sandy medium heavy strong columnar or mottled, neutral pH brown clay coarse blocky lower subsoil olive yellow coarse sandy medium clay massive mottled, neutral pH Hanmer surface soil dark brown sandy loam to clay loam weak polyhedral to loose or hard setting, gravelly, medium acid massive upper subsoil yellowish red to reddish brown heavy clay weak polyhedral to may be mottled, strongly acid blocky lower subsoil yellowish red to light reddish medium to light clay weak blocky very strongly acid, coarse fragments, mottled grey Karangi surface soil brown to dark brown clay loam to sandy clay loam massive hard setting, gravelly, medium acid, bleached subsurface upper subsoil reddish brown, brown or medium heavy clay moderate blocky or coarse fragments, medium acid, may be mottled yellowish brown columnar lower subsoil brownish yellow medium clay massive coarse fragments. slightly acid Leyburn surface soil dark brown to dark yellowish fine sandy clay loam to loamy massive hard setting, bleached subsurface, medium acid to neutral brown sand pH upper subsoil yellowish brown to brown medium clay blocky or columnar may be mottled, slightly acid lower subsoil yellowish brown medium clay massive mildly alkaline SOIL COLOUR TEXTURE STRUCTURE OTHER PROFILE CHARACTERISTICS Lyra surface soil greyish brown to dark brown clay loam massive hard setting, bleached subsurface, slightly acid to neutral pH moderately alkaline upper subsoil light yellowish brown medium heavy clay blocky or columnar strongly alkaline lower subsoil light yellowish brown coarse sandy light medium clay massive Mardon surface soil dark brown to dark reddish coarse sandy loam moderate granular gravelly, medium to slightly acid brown upper subsoil dark reddish brown to brown coarse sandy clay loam massive slightly acid, quartz and sandstone lower subsoil yellowish red coarse sandy light clay massive neutral pH, quartz and sandstone Maxland surface soil dark brown to greyish brown loamy sand to sandy clay loam massive hard setting, bleached subsurface, slightly acid upper subsoil greyish brown sandy medium clay strong columnar or strongly alkaline, may be mottled blocky lower subsoil yellowish brown coarse sandy light clay massive very strongly alkaline Pozieres surface soil very dark grey to dark greyish loamy coarse sand to coarse weak granular to massive very strongly acid, may have a bleached subsurface brown sandy loam massive upper subsoil light grey loamy coarse sand massive medium acid lower subsoil light grey loamy coarse sand may have a hardpan, medium acid Pratten surface soil very dark brown to black heavy clay strong blocky cracking, may be self-mulching, moderately alkaline upper subsoil very dark grey to very dark heavy clay strong blocky calcareous nodules and soft segregations, strongly alkaline greyish brown lower subsoil dark greyish brown heavy clay strong lenticular calcareous nodules and soft segregations, very strongly alkaline Rodger surface soil very dark greyish brown clay loam massive to weak granular hard setting, bleached subsurface, neutral pH strong blocky or upper subsoil very dark grey medium heavy clay columnar neutral pH moderate blocky to lower subsoil greyish brown to brown medium heavy clay to medium massive calcareous soft segregations, strongly alkaline clay N CJ'I LandResources 4. 3 Land suitability 4.3.1 Introduction Evaluating the characteristics of a parcel of land is essential in determining its land use potential. All landholders evaluate land to some degree when deciding what use it is best suited to, for example, cropping or grazing. A number of scientific land evaluation systems have been developed around Australia to help landholders make the best decisions for use and management of their land. Each system involves deciding what alternative land uses could be appropriate, what land and soil requirements each use has, and then measuring the attributes of the land and soil to see if they satisfy these requirements. The land is then given a rating to indicate its suitability for different uses. A formal rating system was not used in this Manual to determine the suitability of each land type for different uses. Instead, suitabilities were determined by assessing the land's characteristics, such as soil type and depth, slope and rock outcrop, and climate, and using local knowledge and experience. The land type sheets in this Manual contain the outcomes of this assessment, while this chapter is a brief overview of that information. The area covered by this Manual is very diverse in its land types and potential land uses. Agricultural uses range from vegetables and fruit-tree plantations, to sheep and cattle grazing, to broadacre cereal cropping. A summary of the broad suitability classes for each land type is provided in Table 4.2. 4.3.2 Suitability of alluvialla nd types Alluvial land types are usually productive compared to the other land types because of a relative lack of limitations. The Mixed basalt alluvial plains, for instance, aresuitable for a wide range of crops including wheat, sorghum, maize and irrigated fodder crops, because of their gentle topography and deep, highly fertile, well structured soils. The Granite/traprock alluvial plains are less productive. They are more prone to floodingand the Rodger soil is less suitable for cropping because it has a lower water holding capacity, and can be sodic and saline. Although they have a limited suitability for cropping, they are suitable for growing lucerne and improved pastures. The Traprock/sandstone alluvial plains are moderately deep, especially when compared to the surrounding traprock hills. Consequently, they have some potential for growing grain, fodder crops and lucerne. However, they are mostly suited to grazing improved pastures due to the major limitations of waterlogging, flooding, restricted workability and low water holding capacity. 26 LandResources Table 4.2 Land use suitabilityfo r land types in the Stanthorpe-Rosenthal region Land Dominant Land Use Suitability Type Soil Grain Hortic Improved Native Crops Crops Pasture Pasture Mixed basalt alluvial plains Pratten s NS s s Granite/traprock alluvial plains Rodger LS NS s s Traprock/sandstone alluvial plains Leyburn LS NS s s Rolling granite mountains Banca NS NS NS LS Granite hills Banca NS LS LS s Undulating low granite hills Banca LS LS LS s Granite rises-uniform sands Pozieres LS s s s Elevated granite plains Cottonvale NS s s s Undulating granite plains Cottonvale NS s s s Granite rises-texture contrast soils Greymare LS LS s s Flat granite plains Lyra NS NS LS s Sandstone ridges Hanmer NS NS NS LS Undulating low sandstone hills Dalveen NS NS LS s Mardon LS LS s s Undulating sandstone rises Allan LS LS s s Gently undulating sandy rises Bonnie Doon NS NS s s Drome NS NS s s Gently undulating sandstone plains Maxi and NS NS s s Traprock mountains Gammie NS NS NS LS Karangi NS NS NS LS Undulating to rolling traprock hills Gammie NS NS NS s Karangi NS NS NS s Low traprock hills Gammie NS NS NS s Karangi NS NS NS s Traprock plains Karangi NS NS LS s Elevated low traprock hills Glentanna NS NS s s S = Suitable NS =Not Suitable LS = Limited Suitability 27 LandResources 4.3.3 Suitability of granite land types The topography of the GraniteBe lt is extremely variable and consequently its suitability for land uses, such as horticulture, is also variable. The Granite Belt is known for its suitability for horticulture and viticulture. Its cool climate and deep sandy soils are two of the characteristics that make it highly suitable for these enterprises. Specific land types most suited to horticulture are the non-rocky and gently sloping areas, such as the Elevated granite plains, the Granite rises - uniform sands and the Undulating granite plains with the deeper Cottonvale and Pozieres soils. Both soils, however, do require substantial inputs for production, namely water and nutrients, to overcome low water holding capacity and low nutrient status. The Cottonvale soils may also have problems with waterlogging. An area of Undulating granite plains around Storm King Darn, is mostly unsuited to horticultural production because of unfavourable climatic conditions, and traditionally land in the north of the Manual area has not been used for horticulture, but for grazing instead. All of these land types are suitable for grazing native or improved pastures. The rockier land types; Rolling granite mountains and Granite hills with shallow Banca soils, are very limited in their suitability for agricultural land uses. They are best left in their natural state for parks, nature conservation, honey production and minimal grazing. However, small pockets of less rocky areas within these land types can and are used for vines, horticulture and improved pastures. The less rocky Undulating low granite hills are also constrained in their agricultural use because of rock outcrop. However, some areas can be sown to improved pastures and fodder crops, and they are suitable for grazing native pastures. Horticultural crops can also be grown if water is available. Grazing of native and improved pastures is the most suitable use for the Greyrnare soils of the Granite rises - texture contrast soils. This is due to their impermeable, poorly structured and sodic subsoils, low fertility, restricted workability and proneness to waterlogging. However, they can occasionally be used for fodder cropping if appropriate management practices are implemented. The Granite plains with Lyra soils have similar limitations to agricultural use as the Greyrnare soils, but of greater severity. They are best suited to the grazing of native pastures only. 4.3.4 Suitability of sandstone land typ es In general, the sandstone land types have many limitations that preclude them from intensive uses such as cropping. If any are cropped they require high levels of management to prevent land degradation. The Sandstone ridges are best suited to light grazing of native pastures because of hard setting surfaces, low water holding capacity, low fertility and restricted workability of the Hanmer soils, and steep scarp slopes. The Undulating low sandstone hills south of Warwick have two dominant soils which have different limitations. The texture contrast Dalveen soil is best suited to grazing of native pastures, unless it has a topsoil deeper than 30 ernand then improved pastures can be sown. This is due to it having low water holding capacity, low fertility, restricted workability and sodic subsoils. 28 LandResources However, the Mardon soil is more fertile, more permeable and non-sadie and can be used, with intensive erosion control measures, for short-term cereal and fodder cropping, improved pastures, and horticulture. The Undulating sandstone rises land type is probably the most productive sandstone land type. The dominant soil, Allan, is usually deep and well structured, enabling it to be cropped occasionally for cereals and forage crops, and horticultural crops. However, intensive management is needed, such as erosion control and ley pastures, to overcome a hard setting surface, low fertility and low water holding capacity. The Gently undulating sandy rises and the Gently undulating sandstone plains that occur near Leyburn are limited to grazing on sown pastures because of the low water holding capacity and low fertility of the major soils; Bonnie Doon, Drome and Maxland. Bonnie Doon and Maxland are prone to waterlogging, and have subsoils that are highly sadie and erodible. 4.3.5 Suitability of traprock land typ es The traprock land types mainly have steep and rocky slopes and shallow, infertile, erodible and low water holding soils. Consequently, grazing of native pastures is usually their most suitable land use. Only the Traprock low hills and Traprock plains, with the deeper Karangi soils and gentler slopes, can be used for sown pastures. However, a high level of management is required as these soils are still impermeable, erodible, low in fertility and gravelly. The Elevated low traprock hills with the Glentanna soil, near Dalveen, have different characteristics from the rest of the traprock hills and are suited to a wider range of land uses. Some minor soils within this unit are more fertile, better structured and permeable, and can be used for improved pastures and short-term fodder cropping. However, high levels of management are necessary as they can be shallow, gravelly and difficult to work. 4.4 Soil properties and characteristics important to land management Many soil properties and characteristics adversely affect agricultural production, as indicated by reduced productivity and/or land degradation. An understanding of these properties and characteristics is essential if management requirements and appropriate strategies, such as fertiliser inputs, are to be developed for the soils of the region. 29 LandResources 4.4.1 Fertility The chemical properties of soil play a vital role in plant growth and soil stability through their effects on nutrition, toxicity and soil physical condition. Soil tests or analyses should now be an integral part of all management strategies. They are useful in providing a guide for fertiliser requirements and to monitor trends. Table 4.3 gives a summary of the surface soil fertility at sites selected as example soil profiles for each soil. It must be stressed that the data represent single, point sites and that there will be a range of values for each particular soil. The limited data does not allow us to give an estimate of the extent to which sampled sites are representative of other members of a given soil. However, the data can be used to give a general indication of local trends, or as bench mark data for later comparisons. Table 4.3 Summary of su;face soil fe rtilityfo r cropping (at the sampled site) SOIL pH Organic Total C/N Available Available Available carbon nitrogen ratio phosphorus potassium zinc Allan 7.0 low low 20 low medium medium ...... �···························-········· ······························· Banco 6.2 low low 1 0 low medium medium ••••••••••••••••••••••••••••••••••••••••••••••••••••••••• ''''''''''''''"'"'''''"'"""""""'''''"''''"''"""""""""""""""""'""'"'''''"''''''''"''''''''''"'''"''''"""'" ""'"'''''''''''''''"'"'""""""""Mooooooooooooooo••••••••••••�••••••••• �•••••••••••••••••••••••••••••• Bonnie Doon 6.0 low low 14 low medium medium- ...... hi g...... h . .. g9.1':t9.1}Y.g!�...... �.�9.���---·- .. !9Y! . f::!.} ...... 1.� ...... �.� 9.i.��...... Q!.9. � ...... �!g .�·················· Dalveen 6.7 low- low 15 low high medium medium ························································· ··············-···························-··························································-···································-···························-·········-······························ i .. _��- · · ····· !?.�. .. §g���� ...... 9.:?...... !9Y!...... !9.�...... �-�-...... �-�9.i.�.�...... !:!!.9. � ...... �.� 9.���-·-· .. ·· .. S?..1.�Qt9.1}.1}.9...... 9.:9...... Y�!.Y.. �!.9.� ...... �!.9.�...... �-�...... _ .. �!g_�...... Y.�-�Y. .. Q.i9 � ...... �-� 9.i.��...... ..S?..��Y.� 9.��...... ?..:?. ��9.i.��...... !C?Y!...... �-�...... _ .. !9.�...... !:!!.9.� ...... !9.� ...... ..!j_g Q��.� ...... �:9...... �!g .� ...... ��g -��� ...... ?. �...... '!..��Y.. !9.� ...... ��S�!�. � ...... Y��Y .. �!g.�...... .. �9-�9_Qg!...... f:!.:9 ...... �. �9.���--... .. ��9-��� ...... J.9...... -. Y..��Y.. !9.Y! ...... ��s�!� .� ---·-·········-··�·�9.i.��-······· i ..�.�Y .9.��Q...... !9.� ...... !9Y! ...... i _��- · - ····· f:!.:9. ?.9. !9.�...... Q .Q� ...... �.�g_ .. �Y.!.g...... ��. 9!�.� ...... Y��Y .. �!g_�-.... . f::!.:9...... �-�9.���--·--····!9Y!...... J? ...... !9.Y! .. �g!.9S?.Q...... �L ...... �!g _�--·············-···-�-�9.i.��...... �}...... � !g_�...... ��9.!�� ...... �. !g.�...... Maxland 6.5 low low 16 low low low ························································· ...... -···································-···························-·········�···· ·························· . .P.S>:?i.���� ...... A:9...... ��9-���--..·· ..! 9.� ...... ?:? ...... _ .. �.�9.i.�.�...... ��. 9!�.� ...... �!g.� ...... . .P.�gt!:�Q ...... !9Y! ...... !9.� ...... �!g.�---······.. ····· ...... Q!9 � ...... !9.Y! ...... �:9 ...... J� Rodger 6.8 high medium 13 medium very high medium The analytical methods for these soil tests are described in Bruce and Rayment (1982). All analyses were carried out on 0- 10 em bulked samples from undisturbed sites (apart from Pratten). Ratings used for classifying the results are those used by Bruce and Rayment (1982) and Hazelton and Murphy (eds) (1992) and are as follows: 30 LandResources Soil Test Ratings very low low medium high very high Organic carbon (%) <0.5 0.5-1 .5 1.5-2.5 2.5-5.0 >5.0 Total nitrogen (%) <0.05 0.05-0. 15 0.15-0.25 0.25-0.50 >0.50 Carbon/nitrogen ratio <8 8-10 10-15 15-25 >25 Available phosphorus (mg/kg) <10 10-20 20-40 40-1 00 >100 Available potassium <0. 1 0.1-0.2 0.2-0.5 0.5-1 .0 >1 .0 (meq/100g) Available zinc (mg/kg) pH>7 <0.3 0.3-0.8 0.8-5.0 5.0-15 >15 pH<7 <0.2 0.2-0.5 0.5-5.0 5.0-15 >15 The natural fertility of cropping and pasture soils in the region is declining with time. More frequent opportunity cropping and the use of higher yielding varieties requires growers to monitor nutrient levels as part of their existing management programs. Pastures, grain legume rotations and fertilisers are important to the maintenance of soil fertility in this region. Soil pH The pH of soil is a measure of its acidity or alkalinity and is important in determining the degree and likelihood of acidification, in estimating possible nutrient deficiencies and assessing suitability for certain crops. Although theywill tolerate a range in pH conditions from 5.5 to 8.5, most plants grow best when soil pH is between 6.0 and 7.5. Most soils within the region have a surface soil pH between 5.5 and 7.0. If a soil is excessively acid (pH<5.2), aluminium and manganese can become available in the soil in large quantities that are toxic to many plants. On the other hand, if soils are excessively alkaline (pH>7 .0), trace elements such as zinc, iron, copper and boron become less available and can lead to deficiencies in plants (Lines-Kelly 1994). It is possible that the high levels of exchangeable aluminium in thePozieres soils (pH of surface soil <5.0) are associated with poor growth on these acid soils. Consequently, Pozieres soils should show large responses to liming. However, to lessen soil acidity in the subsoil, where the majority of roots occur, pre-planting lime applications distributed throughout the profile by deep ploughing should be considered. Organic carbon and nitrogen Organic carbon (OC) is the main component of organic matter and acts as a soil aggregate stabiliser, thereby improving porosity, and as a storehouse for nutrients. Soils with low or very low organic carbon values indicates low levels of organic matter in the soil, suggesting low fertility. The levels of organic carbon in the soils will vary depending on land use. Most of the soils with low OC values in the region have either sandy surfaces or they are cropped. 31 LandResources The majority of total nitrogen (N) within the organic matter fraction of a soil is not immediately available to plants, some however may be mineralised to available forms. Low to very low values of total N indicate potential problems of availability for plant growth (since only a fraction is available). The use of fertilisers or legumes may be needed to correct N deficiency. The ratio of carbon to nitrogen (C/N) is often a more useful indicator of the ability of the soil to supply N in an available form (Hazelton & Murphy (eds) 1992). A C/N ratio of 10-15 is normal for an arable soil. High figures (15-25) indicate a slowing in the decomposition process (mineralisation) while a very high ratio (>25) shows thatthe organic matter is unlikely to breakdown quickly, e.g. Drome with a C/N of 38. Where the ratio is low or very low ( <1 0), the organic matter is likely to break down very rapidly (e.g. pea stubble). Phosphorus Many of the soils sampled had low or very low levels of available (extractable) phosphorus (P) which will limit plant growth. Because P is not very mobile, phosphate fertilisers are most efficient when applied at planting in direct contact with the seed. Long fallows due to crop rotation or drought will accentuate the responsiveness of a soil to phosphate fertiliser due to the absence of mycorrhizae (soil fungi which act as extensions to plant roots, helping roots take in more nutrients). Ahern et al.(1 994) state that pasture yield and quality, and hence animal production continue to increase as soil P increases from 4 mg/kg and reach a maximum between 8 and 10 mglkg. They use the following categories to rate soil P levels for pasture growth. Soil P (mg/kg) Rating <4 extremely low 4-6 very low 7-9 low 10-15 medium 16-25 high >25 very high Although there is little evidence of production responses from providing additional phosphorus to cattle on land with P values greater than 10 mg/kg (Ahern et al. 1994), the extra categories provide greater certainty on whether or not the P status is adequate. In grazing situations, the introduction of legumes into grass pastures can improve animal production, without the use of phosphorus fertilisers, on soils with low P levels (Shields & Anderson 1989). 32 LandResources When interpreting P values other factors need to be considered (Baker & Eldershaw 1993). Some of these factors include: e there are differences in P uptake by different crops, for example, legumes have a larger requirement than grasses; thus the amounts removed over time (cropping history) should be considered as well as the potential demands of current crops. Under permanent pasture, phosphate fertilisers tend to accumulate in the surface zone as organic (unavailable) P; e a high value of available P in soils regularly fertilised, could provide an opportunity to reduce levels of P fertiliser; and e P applications on P deficient soils can produce limited growth responses because of a second limiting deficiency - the most likely ones are nitrogen and potassium. Potassium Most soils sampled have adequate available (extractable) potassium (K) levels. Baker and Eldershaw (1993) list a number of instances where economic returns are most likely from the use of K fertilisers. They are: e on soils low in both exchangeable K and total forms, for example, sandstone and some shale soils; e where soil moisture from either rainfall or irrigation is sufficient to allow uninterrupted growth during the growing season; e where heavy removal of K is likely, as in hay cutting or forage harvesting; and e where large amounts of K are transferred off the site via the animal, as in strip grazing and the use of night paddocks on dairy farms. Zinc Zinc (Zn) plays a vital role in a plant's ability to use nitrogen and transform it into yield and protein. Soils with low to very low available zinc levels are below the critical soil Zn levels. Example soils with critical Zn levels include Greymare, Maxland and Pratten. Zinc related problems are closely linked to pH - increasing pH reduces Zn availability, e.g. Pratten soil. Zinc deficiencies in crops are not common in acid soils. The availability of zinc to many crops is increased by the presence of mycorrhizae in the soil. Crops following long fallows or other events that deplete soil mycorrhizal population will be most at risk of suffering zinc deficiency. Response to zinc fertiliser occurs frequently in old cultivation on heavy clay soils with high soil pH levels. Soil erosion, soil structural problems (e.g. hard pans) and root diseases can all increase the likelihood of Zn deficiency. Zinc deficient winter cereal crops often have a patchy appearance. The plants are stunted with short, thin stems and usually pale green foliage. The first symptoms in wheat appear on middle leaves and develop in the lower half of the leaf, as yellow chlorotic areas between the mid vein and leaf margin and extend outward towards the tip and the base of the leaf. These chlorotic areas eventually die and turn pale grey or brown. 33 LandResources There are a number of methods to correct Zn deficiency. The most common is soil applied zinc sulfate which will last for a number of years. Foliar sprays or zinc applied at planting with the seed have also been successful. Interpreting soil analyses As a guide to the generalised ratings given in Table 4.3 the following statements can be made (this guide is takenfrom Bruce & Rayment 1982): • very low or low ratings are usually undesirable for optimum crop production. When very low or low ratings for P, K and Zn are recorded, the fertiliser rate required usually equals the highest normally recommended in the district for the specificcrop being grown; • medium ratings for P, K and Zn indicate a level of soil fertility at which only small (if any) responses to these nutrients are likely for most agricultural crops and pastures under dry land conditions. Fertiliser recommendations for P and K should be below the district average; usually no Zn would be required; and • high or very high ratings indicate no fertiliser would normally be recommended for crops and pastures. 4.4.2 Moisture availability One of the main functions of soil is to store moisture and supply it to plants between rainfall or irrigations. If the water content becomes too low, plants become stressed. The plant available water capacity (P AWC) of a soil provides a buffer which determines a plant's capacity to withstand dry spells (Soil Pit Field Day 1992). Decisions about what crops to grow, sowing times and density of planting are made on the basis of the amount of water stored in the soil, and the expectations of rain in the coming season. Soil properties that affect P AWC include: • the ability of the soil to retain moisture - determined by the number and size of pore spaces. Because the total and available moisture storage capacity are linked to porosity, the particle sizes (soil texture) and their arrangement (soil structure) are the critical factors. Evaporation from the soil surface, transpiration by plants and deep drainage are also important; • the effective rooting depth - an estimate of the long-term depth of wetting within a soil. It is measured as the depth to which salts have been leached (usually where the salt content in a soil makes an abrupt rise). It may also represent thedepth to severe physical or chemical barriers that restrict root growth, such as dense gravel or stone layers, impermeable sodic clay subsoils, or strongly acid clay subsoils; 34 LandResources • surface soil characteristics that reduce infiltration and increase runoff structureless or poorly structured surface soils which have high levels of fine sand, silt or dispersible clay and low levels of organic matter are usually prone to surface sealing after rain. They may also be hard setting or crust on drying; and • landscape position - steep slopes increase runoff, decreasing infiltration and subsequent water storage. In flat, poorly drained or floodedare as, water supply may exceed P Awe making soils waterlogged. All the air in the pores is displaced by water, so no oxygen is available to plant roots or for soil microbial activity. If waterlogging continues for a long period, plants die. Table 4.4 gives an estimate of the PAWe (measured in millimetres of water) in the root zone for the example soil profiles. These estimates have been derived using the method of M. Littleboy (pers. com.) and use the following ratings to interpret the results. PAWC in root zone Rating (mm) <50 very low 50-100 low 100-1 50 medium 150-200 high >200 very high The effective rooting depth (see Table 4.4), and hence the PAWe, is reduced in most soils by the accumulation of salt or an impermeable subsoil due to high sodicity levels. The low to very low PAwe figures for themain horticultural soils of the Granite Belt highlight the need for supplementary irrigation. 4.4.3 Salinity Salinity refers to the concentration of soluble salts in a soil. These salts are dissolved in the soil water and move down the profile by leaching or into plant roots by uptake. Plant growth is affected by high levels of soluble salts which reduce the availability of water to plants as well as specific element toxicities and nutrient disorders. 35 (.,) 0') Table 4.4 Important agronomic characteristics of the soils (at the sampled sites) SOIL pH SALINITY SODICITY DISPERSION Ca/Mg RATIO CLAY CONTENT EFFECTIVE ROOTING PAWC IN ROOT RATIO (R1) (%) DEPTH (cm) ZONE (mm) Allan surface soil 6.7 very low sodic medium 1.3 15-20 65 80 upper subsoil 6.7 very low sodic medium 0.7 35-40 lower subsoil 9.2 medium strongl:i sodic low 0.7 40-45 Banca surface soil 6.2 very low non-sodic 7.7 15-20 depth to hardpan or rock, 25-43 (depends on upper subsoil 6.2 very low non-sodic 8.0 15-20 usually 25-50 profile depth) lower subsoil 6.5 very low non-sodic 3.1 20-25 Bonnie Doon surface soil 6.2 very low non-sodic medium 1.7 10-15 30-60 (surface soil depth) 37-56 (depends on upper subsoil 5.5 very low sodic 0.1 30-35 surface depth) lower subsoil 5.4 very low non-sodic <0.1 35-40 Cottonvale surface soil 5.8 very low non-sodic low 0.9 15-20 30-45 (surface soil depth) 37-50 (depends on upper subsoil 4.3 medium strongly sodic low <0.1 45-50 surface depth) lower subsoil 4.5 medium strongl:i sodic low <0.1 30-35 Dalveen surface soil 6.5 low non-sodic low 2.2 15-20 10-60 (surface soil depth) 15-53 (depends on upper subsoil 6.7 very low non-sodic low 1.1 50-55 surface depth) lower subsoil 6.8 very low non-sodic low 0.9 50-55 Drome surface soil 5.8 very low non-sodic low 1.5 0-5 110 (profile depth) 66 (depends on upper subsoil 6.3 very low non-sodic low 0.3 0-5 profile depth) lower subsoil 6.6 very low non-sodic low <0.1 0-5 Gammie surface soil 6.8 very low non-sodic medium 3.7 30-35 20 (depth to weathered 29 (depends on upper subsoil 7.7 very low sodic medium 2.5 30-35 rock) profile depth) Glentanna surface soil 6.3 very low non-sodic low 3.0 30-35 60 (profile depth or depth to 87-101 (depends on upper subsoil 6.7 very low non-sodic low 1.9 70-75 hard rock) profile depth and lower subsoil 7.5 very low non-sodic low 1.6 70-75 stone content) Greymare surface soil 7.0 very low non-sodic medium 4.0 10-15 30-60 36-58 (depends on upper subsoil 7.0 high sodic medium 1.0 35-40 (surface soil depth) surface depth) lower subsoil 7.1 medium sodic medium 1.2 20-25 SOIL pH SALINITY SODICITY DISPERSION Ca/Mg RATIO CLAY CONTENT (%) EFFECTIVE ROOTING PAWC IN ROOT RATIO (R1) DEPTH (cm) ZONE (mm) ------Hanmer surface soil 5.7 very low sodic low 2.4 15-20 50 37-62 (depends on upper subsoil 5.1 very low non-sodic low <0.1 50-55 gravel and stone lower subsoil 5.2 ver'f. low non-sodic low <0.1 55-60 content) Karangi surface soil 6.0 very low non-sodic medium 1.6 10-15 50 22-64 (depends on upper subsoil 6.0 very low sodic high 0.1 40-45 rock content) lower subsoil 6.3 medium stronglY.sodic high <0.1 40-45 Leyburn surface soil 7.0 very low non-sodic rnedium 2.2 15-20 50 57 upper subsoil 6.1 very low sodic medium 0.8 25-30 (surface soil depth) lower subsoil 7.7 high-medium stronglY. sodic high 0.7 25-30 Lyra surface soil 6.3 very low non-sodic high 2.4 10-15 10-35 15-36 (depends on upper subsoil 6.6 rnedium strongly sodic high <0.1 20-25 (surface soil depth) surface depth) lower subsoil 8.9 medium stronglY. sodic high <0.1 20-25 Mardon surface soil 6.3 low non-sodic low 3.6 15-20 90 37-68 (depends on upper subsoil 6.5 very low non-sodic low 1.5 15-20 (profile depth) gravel and rock lower subsoil 7.1 ver'f. low non-sodic medium 1.2 15-20 content) Maxland surface soil 6.1 low non-sodic medium 3.3 5-10 20-40 26-42 (depends on upper subsoil 8.5 low strongly sodic high 0.5 35-40 (depending on surface soil surface depth) lower subsoil 9.1 high stronglY. sodic high 1.3 15-20 depth) Pozieres surface soil 4.9 very low non-sodic medium 1.9 5-1 0 depth to hardpan or rock, 39-59 (depends on upper subsoil 5.6 very low non-sodic high 0.5 0-5 usually 60-90 profile depth) lower subsoil 5.6 ver'f. low non-sodic high 0.4 0-5 Pratten surface soil 7.9 very low non-sodic low 0.8 60-65 50-80 (depends on depth 93-133 upper subsoil 8.7 low sodic medium 0.7 65-70 to salt bulge) lower subsoil 9.3 ver'i.high-high stronglY. sodic high 0.2 50-55 Rodger surface soil 7.1 very low non-sodic low 3.5 20-25 110 (or shallower 95 upper subsoil 7.3 very low non-sodic medium 3.5 40-45 depending on subsoil lower subsoil 8.8 low non-sodic medium 3.3 25-30 structure) w ...... LandResources Table 4.4 shows that most soils throughout the Granite Belt are non-saline. The exceptions to this are some of the low-lying, texture contrast soils - Greymare, Leybum, Lyra, and Maxland, and the uniform clay soil, Pratten. As previously mentioned, these high salinity levels have a marked influence onthe effective rooting depth and hence the PA WC. This is particularly evident for Pratten at the sampled site, where an increase in effective rooting depth would considerably increase the P A WC. However, research by Dalal ( 1986) has shown that cultivation does cause the leaching of salts downwards over time, in cropping country on clay soils. The electrical conductivity (EC) of the soil solution (given for each example soil profile in Appendix 3) is used to estimate soil salinity. The following ratings are used to interpret the results. Average root zone salinity for differing clay content ranges EC 1:5 dS/m Salinity 10-20% clay 20-40% clay 40-60% clay 60-80% clay Rating very low <0.05 <0.08 <0.12 <0. 18 low 0. 10 0. 165 0.25 0.37 medium 0.25 0.40 0.58 0.85 high 0.45 0.67 1.00 1.5 very high 0.70 1.05 1.58 2.4 extreme >0.70 > 1.05 > 1 .58 >2.4 Source: R. Shaw, 1988 4.4.4 Sodicity and dispersion Sodicity is caused by the presence of sodium held on the surface of clay particles in a soil. Sodicity becomes a problem when it reaches a concentration where it starts to affect the soil structure (Rengasamy & Walters (comps) 1994). A sodic soil is defined as one in which the sodium makes up 6% or more of the exchangeable cations (i.e. the exchangeable sodium percentage, ESP, is 6 or greater - see below). Sodicity rating ESP (%) non-sodic <6 sodic 6-15 strongly sodic >15 The sodium weakens the bonds between soil particles when they are wetted making clays swell then disperse. Dispersion can be seen as cloudy water. The dispersed clay acts as a filler and binder - it clogs the pores in a soil reducing infiltration and drainage, and increases the size and density of aggregates. It is 38 Land Resources often observed that these soils have impermeable, dense subsoils that restrict root activity and water uptake. Examples of this are the subsoils of Allan, Cottonvale, Greymare, Karangi, Leybum, Lyra, Maxland and Pratten. Symptoms that are typical of a sodicity problem in the root zone of plants include poor infiltration and drainage resulting in waterlogging, increased runoff and poor water storage, surface crusting, poor emergence of crops and pastures, problems with cultivation (hard surface crusts or sealing when dry), gully erosion and tunnel erosion in sloping country (Rengasamy & Walters (camps) 1994). Table 4.4 shows that soils which are sadie or strongly sadie may also have medium to very high salinity levels - examples include the subsoils of Leybum, Lyra, Maxland and Pratten. In these soils the salt prevents the clay particles from dispersing and any difficulties experienced managing these soils will be due to salinity not sodicity. However, if the salts are leached from these soils, sodicity symptoms may start to appear, that is, increased dispersion and reduced water and air movement throughoutthe soil profile. Management practices which may bring sadie soils to the surface, e.g. deep tillage or levelling, are not recommended. Sealing and crusting problems will occur if the sadie clays are incorporated with the surface layer. Gypsum can be used to improve the structure of sadie clays. Table 4.4 also shows two other soil characteristics that are used to assess soil physical behaviour - the dispersion ratio and theCa/Mg ra tio. Both ratios should always be considered in conjunction with ESP values. The dispersion ratio, R1, gives an indication of the dispersibility of soil layers and is particularly important in soils with a high clay content, especially in areas which experience high rainfall intensities. The table below gives an interpretation of R1 values. Rating Dispersion ratio (tendency to disperse) Rl low <0.6 medium 0.6-0.8 high >0.8 The R1 values are taken from example soil profiles in Appendix 3. Soils with a Ca/Mg ratio of <1 exhibit a dominance of magnesium in their subsoils indicating cation imbalance and an increase in the dispersion tendency (even at low ESP). Examples of soils with low subsoil ratios, which are impermeable and dense, include Bonnie Doon, Cottonvale, Karangi, Leyburn, Lyra and Pratten. 39 LandResources Further Reading Doherty, J. and Stallman, A. 1992, Land management options fo r salt-affe cted catchments on the Darling Downs, Queensland Department of Primary Industries Project Report Q0920 10. Marshall, J.P., Crothers, R.B., Macnish, S.E. and Mullins, J.A. 1988, Land management field manual fo r south-east Darling Downs districts, Queensland Department of Primary Industries Training Series QE88001. Mills, W., Mcintyre, G. and Lucy, M. 1993, Darling Downs summer crop management notes, 1993- 1994, Department of Primary Industries, Queensland. Thorburn, P. 1989, Causes, identification and management of drylandsalinity on the Darling Downs, Queensland Department of Primary Industries. Vandersee, B.E. 1975, Land inventory and technical guide, EasternDowns area, Queensland, Technical Bulletin No. 7, Division of Land Utilisation, Queensland Department of Primary Industries. 40 5. VEGETATION Bruce Wilson The vegetation of the Stanthorpe-Rosenthal region is mainly Eucalyptus dominated woodland and open forest, with small, but biologically significant, areas of closed forest (dry rainforest or scrub), open scrub, grassland and sedgeland communities. A feature of the flora ofthe area is the presence of many temperate adapted species that do not occur further north in Queensland. For example, species such as snow gum (Eucalyp tus pauciflora) and manna gum (E. viminalis), are found extensively throughout temperate parts of New South Wales but only occur in Queensland in the Rosenthal and Stanthorpe region, and some adjacent areas. In addition, there are localised occurrences of species some of which have only been described by botanists recently. Some noteworthy examples are Eucalyptus terrica and E. interstans. These species are mostly found in the more rugged hills and ranges. Vegetation in this area is strongly correlated with geology and its associated soils, and topography. Land use and clearing patterns also follow these fe atures. Thus vegetation occurring on the more rugged hills and ranges is largely uncleared while there is extensive cleared/semi-cleared land on more undulating hills and flats (see Land Cover Maps 4 and 5). A description of major vegetation types, or floristic associations, is given in Table 5.1. A list of plants commonly found in the area is given in Appendix 1. 41 ,f::o. 1\.) Table 5.1 Description of major vegetation types Vegetation type Land type Dominant species Associated species Comments a) Vegetation occurring on broad alluvial plains blue gum open forest mixed basalt alluvial plains blue gum and/or river red river sheoak restricted to the fringes of the Condamine gum River; largely cleared except for banks; important habitat for arboreal mammals and birds poplar box grassy woodland granite/traprock alluvial poplar box rough barked apple virtually all cleared for crops and plains, and pastures; little is represented in traprock/sandstone alluvial conservation reserves; important habitat plains for arboreal mammals and birds Blakely's red gum and/or granite/traprock alluvial Blakely's red gum and/or manna gum, rough barked apple, found on alluvium derived from granite; fuzzy box grassy woodland plains, and fuzzy box or New England mountain gum, yellow box, blue gum, extensively cleared; habitat for rare and flat granite plains peppermint apple box, broad leaved stringybark, threatened species including E. Youman's stringybark magnificata, Macrozamia viridis, Pterostylis woolsii, Grevillea scortechinii, Acacia ruppii; important habitat fo r arboreal mammals and birds manna gum open forest granite/traprock alluvial manna gum fringes watercourses; restricted to plains watercourses north of Dalveen; extensively cleared or modified poplar box, gum topped box traprock/sandstone alluvial poplar box, gum topped box blue gum extensively cleared; not represented in open forest plains conservation reserves I Vegetation type Land type Dominant species Associated species Comments b) Vegetation occurring mainly on granite New England blackbutt open rolling granite mountains, New England blackbutt many species co-dominant such as some areas cleared, but extensive areas forest/tall open forest granite rises - uniform round leaved or Deane's gum, broad remain and well represented in Girraween sands, elevated granite leaved stringybark, Tenterfield National Park; mainly limited to highest plains, and undulating woollybutt, yellow box, rough barked parts of Granite Belt (>1 000 m) granite plains apple, with localised occurrences of Sydney blue gum, grey gum, messmate stringybark, narrow leaved peppermint, snow gum and silvertop stringybark mixed species shrubland rolling granite mountains dominated by Acacia spp., habitat for rare and threatened species not cleared - found on rock pavements; Banksia spp. and including Boronia granitica, B. repanda, mainly limited to highest parts of Granite Eucalyp tus spp. B. amabilis, Callitris monticola and Belt (>1000 m); represented in Girraween Homoranthus papillatus and Sundown National Parks swamps rolling granite mountains sedgeland fringed by shrubs not cleared; mainly limited to high and low trees (e.g. mountain altitudes of Granite Belt (> 1000 m) on swamp gum) poorly drained depressions New England peppermint, undulating granite plains, New England peppermint habitat for rare and threatened species very extensively cleared; small area manna gum grassy and granite/traprock alluvial occurs on lower slopes and including Persoonia daphnoides and represented in Girraween National Park woodland plains narrow alluvial flats; manna Grevillea juniperina gum sometimes locally common New England blackbutt granite hills New England blackbutt mixed species upper stratum including well represented in Girraween National shrubby open forest to Youman's stringybark, yellow box, Park with smaller areas in Sundown woodland Tenterfield woollybutt, black cypress National Park pine and orange gum; mid stratum contains scattered shrubs, especially wattles (e.g. Acacia adunca, A. fa lciformis, green wattle, A. neriifolia), I coughbush, wild may, Leucopogon melaleucoides, L. muticus, sticky daisy, rice flower, dogwood ··--- � (,) .j:::l. .j:::l. Vegetation type Land type Dominant species Associated species Comments tumbledown gum, granite hills, granite rises - tumbledown gum, Tenterfield woollybutt, orange gum, occurs on drier parts of the Granite Belt Youman's stringybark, texture contrast soils, and Youman's stringybark, while Caley's ironbark is replaced by and elevated traprock; much of this Caley's ironbark and undulating granite plains Caley's ironbark, black silver leaved ironbark or narrow leaved hillside vegetation remains as it is other species grass/shrubby cypress pine on hillsides ironbark in places unsuitable for clearing; well represented woodland in Sundown National Park broad leaved stringybark, undulating granite plains, broad leaved stringybark, red ash, wattles (e.g. lightwood, A. extensively cleared and restricted to blue gum grassy woodland granite rises - texture blue gum, rusty gum, yellow leucoclada subsp. argentifolia, A. northern slopes of Granite Belt; not contrast soils, undulating box, narrow leaved ironbark neriifolia, sally wattle), dogwood, sticky represented in conservation areas low granite hills, and hopbush, weeping pittosporum; grassy sandstone ridges lower stratum of Queensland bluegrass, wiregrass, barbed-wire grass; herbs such as bluebells are also conspicuous c) Vegetation occurring mainly on sandstone spotted gum, narrow leaved gently undulating sandy spotted gum, narrow leaved mid layer of bull oak or some white this community occurs in scattered ironbark shrubby/grassy rises, gently undulating ironbark, tumbledown gum cypress pine patches on sandstone and traprock; open forest sandstone plains, and (e.g. Mt Burrabaranga, Mt represented in Sundown National Park undulating to rolling Gammie) and rusty gum traprock hills gum topped box grassy gently undulating gum topped box this community is naturally restricted and open forest sandstone plains confined to vicinity of Dalveen vine thicket or 'softwood sandstone ridges small patches of vine thicket extensively cleared with remaining areas scrub' or 'softwood scrub' restricted to isolated pockets narrow leaved ironbark, blue sandstone ridges narrow leaved ironbark, blue mid layer of bull oak or some white extensively cleared gum shrubby/grassy gum, smooth barked apple cypress pine woodland Vegetation type Land type Dominant species Associated species Comments d) Vegetation occurring mainly on traprock grey box with fuzzy box and traprock mountains, low grey box, fuzzy box, yellow poplar box or blue gum on lower very extensively cleared/modified yellow box grassy woodland traprock hills, traprock box slopes, small patches of shrubby plains, undulating silvertop stringybark open forest in sandstone rises, undulating highest parts of Sundown National low sandstone hills, flat Park granite plains, and granite/traprock alluvial plains closed forest (dry rainforest) traprock mountains dominated by a mixture of naturally restricted community fo und I species including giant- growing in rugged gorges in Sundown leaved stinging tree, National Park Hymenanthera dentata and ooline silvertop stringybark, rough traprock mountains silvertop stringybark, rough Tenterfield woollybutt, yellow box well represented in Sundown National barked apple open forest barked apple Park narrow leaved ironbark, elevated low traprock hills, narrow leaved ironbark, white box, white cypress pine; silver extensive on traprock country tumbledown gum mixed undulating to rolling tumbledown gum leaved ironbark replaces narrow leaved species grassy/shrubby traprock hills, and ironbark in an arc along the Severn woodland sandstone ridges River from west of Ballandean to the QLD/NSW border; Eucalyp tus terrica is restricted to a small area south of Mount Burrabaranga mugga ironbark and broad elevated low traprock hills, mugga ironbark, broad leaved grey box, tumbledown gum and in occurs in scattered patches on traprock leaved red ironbark shrubby and low traprock hills red ironbark places mallee eucalypts (E. bal .r:o. (J1 Vegetation Further Reading Heil, Judy 1996, Remnant Vegetation Report - Stanthorpe Shire, Stanthorpe Landcare Group. 46 6. WATER RESOURCES Bevan Vanderwolf and Adrian Mackay 6.1 Introduction There are a number of streams and aquifer systems which comprise the water resources of the area. A diverse range of development and use options exist across the area, and these will be described in detail for both surface and groundwater for the different land types. The major catchment boundaries for the streams in the area are shown in Map 3. The growth of water resource use for intensive horticulture, particularly of groundwater during drought, has led to many groundwater areas being fully committed. Periods of increased use result in significant periods of pumping restrictions for both groundwater and surface water. 6.2 Groundwater resources The occurrence of groundwater within the Manual area is closely related to geology in terms of both rock type and structure. A basic division of the geology relative to aquifer system types within the area is: • unconsolidated alluvium - sands and gravels deposited by stream channels; • consolidated sediments - principally sandstones of the Jurassic Marburg Sandstone; and • fractured rocks - a range of volcanic and low grade metamorphic rocks including traprock and granites. The yields and water quality associated with the various aquifer systems are primarily related to the storage and transmission properties of the aquifer. The degree and extent of fracturing and jointing also influence groundwater occurrence and characteristics, particularly in fractured rock aquifers. Mineralisation has a marked impact on water quality particularly within volcanic and metamorphic rocks. All aquifer systems within the Manual area contain sub-artesian supplies, in that the watertable does not rise above the ground surface. However, spring discharges largely associated with shallow groundwater flowsare reasonably extensive, particularly over the Granite Belt. 47 Water Resources 6.2.1 Aquifers associated with alluvium The limited areas of alluvium which occur within the Manual area are associated with the major creeks and rivers such as the Condamine River to the north and the Dumaresq River to the south-west. Aquifers or waterbeds occur in sand and gravel sections within the alluvium. Supplies are variable depending upon the depth and areal extent of the alluvium, and the sorting of materials. The major alluvial aquifers within the Manual area are contained within the Condamine River alluvium and the Dumaresq River alluvium. Supplies are encountered in the range 1.5-32 litres per second from a maximum depth of 30 m and 60 m respectively. Smaller alluvial systems are associated with the majority of major creeks draining to the Condamine River. Supplies up to 10 litres per second are encountered from a maximum depth of 15-20 m within these systems. Water quality associated with alluvial systems is generally suitable for most purposes - domestic, stock, irrigation, industrial and town water supplies. Alluvial groundwaters provide a valuable source of good quality water supporting a range of production-based enterprises. Average electrical conductivities (EC), or concentration of total soluble salts, are used as a measure of water quality. For alluvial systems these are in the range 1200-1500 microsiemens/cm (see Table 6.1). Table 6.1 Summary of the groundwater resource prospects of the Stanthorpe-Rosenthal region Aquifer type Yield range Depth range Water quality range (litres per second) (metres) (microsiemens/cm) Alluvial major 1.5-32.0 30-60 1200-1 500 minor up to 10.0 15-20 1200-1500 Sandstone 0.1-3.0 50-100 2500-3500 Traprock 0.1-6.0 40-120 2500-1 0000 Granite 0.1-5.0 15-20 200-500 6.2.2 Aquifers associated with sandstone The occurrence of sandstone aquifers is limited to the northern edge of the Manual area surrounding Warwick, a small area near Dalveen and an area south-west of Leybum. Waterbeds occur in porous sandstone sections and limited jointed zones. Supplies are highly variable and are generally in the range 0.1-3.0 litres per second. A suitable supply is usually encountered from depths of up to 50 m, however, it is not uncommon for bores to be completed up to 100 m in depth. 48 N SOUTH A PACIFIC STANTHORPE - ROSENTHAL REGION CATCHMENTS Scale 1 : 550 000 ______---- Stanthorpe-Rosenthal Region 0 10 20 km ______Catchment boundary NATURAL RESOURCES Map 3 Water Resources Water quality is generally suitable for stock and most household domestic applications. Average ECs are in the range 2500-3500 microsiemens/cm (see Table 6.1). The Rosenthal Heights area to the south-west of Warwickhas significantly poorer water quality than the average. Groundwaters in this area may be unsuitable for most stock and have limited domestic uses. 6.2.3 Aquifers associated with traprock (m etamorphics) Aquifer systems in traprock occur over the maj ority of the western half of the Manual area, as localised and discontinuous systems. Waterbeds areloca ted in fractured and jointed zones within the traprock. Supplies are highly variable depending upon the degree of fracturing. Bore yields in the range 0.1 -6.0 litres per second are generally encountered at depths below 40 m and up to a maximum of 120 m. Water quality is generally suitable for most stock, but marginal for domestic applications. These ground waters often contain high concentrations of individual ions. A water analysis is recommended to determine suitability for specific uses. Average ECs are in the range 2500-10 000 microsiemens/cm (see Table 6.1). 6.2.4 Aquifers associated with granites (ad amellites) Aquifer systems in granite occur over the majority of the Granite Belt, in the Greymare area, and within a large proportion of the Leslie Dam catchment. W aterbeds are generally found in porous zones within the weathered granites, and shallow alluvial and colluvial areas to a depth of 15-20 m. Waterbeds are also located in fractured and jointed zones below 20 m, however, supplies are often limited and highly variable. Yields in weathered zones range between 0.1-5.0 litres per second. Wells and excavations are often constructed to enhance supply and provide storage. Water quality is generally suitable for all uses. The shallow groundwaters are a valuable source of water for horticultural enterprises on the Granite Belt. Average water qualities (or ECs) are in the range 200-500 microsiemens/cm (see Table 6.1). 6. 3 Surface water resources The surface water resources of the area are mainly developed through the use of farm dams on the tributaries of the more defined streams, the exception being the Granite Belt area where significant in-stream development has taken place in the form of concrete weirs. 49 Water Resources 6.3.1 Irrigation development There are two major storages located within the area: Leslie Dam on Sandy Creek near Warwick, and Glenlyon Dam on Pike Creek near Texas. Both these storages supply irrigation projects mostly outside the Manual area. The Broadwater Dam Site near Stanthorpe is undergoing detailed planning as a supply to augment existing farm storages. When complete it will provide increased reliability for existing irrigation enterprises of high value horticulture and small crops. Irrigation development has centered on alluvial groundwater and on-farm catchment dams. Water harvesting of surplus and/or higher level flowsin the major watercourses to storages off-stream, is also undertaken. The role of water harvesting is significant on the Granite Belt and guidelines for water harvesting are to be incorporated in the Water Management Plan for the area. Stream flow datais available for the SevernRiver (Sundown National Park) and Canal Creek at Leyburn. Table 6.2 shows the stream flow statistics for these two gauging stations. Average monthly discharges are shown graphically in Figure 6.1. Table 6.2 Flow statistics fo r the SevernRiver and Canal Creek Stream Record Annual discharge (Megalitres) (Station) Period Maximum Minimum Average Median Severn River (Farnboro) 1963 to 1994 3091 52 165 93290 59965 Canal Creek (Leyburn) 1973 to 1992 61340 14 15026 5880 CANAL CREEK SEVERN RIVER 4000 3000 � !:: 2000 :;l"' "' 1000 :; MONTH MONTH Figure 6.1 Average monthly discharges fo r SevernRiver and Canal Creek The Canal Creek statistics show the general seasonal pattern of run-off for most of the Rosenthal area catchment, and the Severn River statistics show the typical runoff patternfor the Granite Belt area. Table 6.3 shows the proportion of rainfall 50 Water Resources which runs off annually as stream flow for the catchment area of the two gauging stations. It indicates the proportion is fairly low. Table 6.3 Catchment rainfa ll and runofffo r the SevernRiver and Canal Creek Stream Station Average annual Average annual Runoff as a percentage rainfall runoff of rainfall (mm) (mm) (%) Severn River Farnboro 805 71 8.8 Canal Creek Leyburn 703 38 5.4 6.3.2 Surface water resources associated with alluvial land types The alluvial plains generally have very limited potential for surface water development. The Mixed basalt alluvial plains often lack an adequate foundation for a surface water storage and are generally developed for irrigation. The Granite/traprock alluvial plains offer some potential with sites for irrigation and stock water storages available with clay generally available for foundation and construction material. Sites across the minor tributary streams offer the greatest potential for an irrigation storage and are generally limited to the narrower, flatter alluvial plains. The Traprock/sandstone alluvial plains are generally steeper and present very limited storage potential. However, sites for stock water storages are available and generally have clay available as a foundation and for construction. 6.3.3 Surface water resources associated with granite land typ es Historically, surface water storages have been developed at the sites where surface springs have been evident, and this subsurface spring flowhas been utilised for recharge of the storage. The Granite hills and Granite mountains land types, due to their steep slopes and rocky nature, offer very limitedpotential for surface water storage development. Small and often shallow sites are available in spots where the rock outcrops are less dominant. Seepage losses from storages can be significant as foundations are often very sandy and construction material has a low clay content. The Granite rises, being less rocky and of lower slope, offer potential for development. Significant development of both stock water and irrigation storages has taken place. Concrete weirs have been constructed on the granite rock in the bed of the streams. The Elevated granite plains and Undulating granite plains are theareas where most of the development has taken place. There is less likelihood of striking rock, however, construction material is most likely of low clay content and seepage losses from any storage can be experienced. 51 Wa ter Resources Granite plains offer limited potential as they are very sandy and sites with suitable foundations and construction material are very limited. 6.3.4 Surface water resources associated with sandstone land typ es The sandstone areas offer reasonable sites topographically, however the underlying soils are often very gravelly and storages experience seepage losses. Detailed soils investigation is recommended as part of the preliminary planning for any surface water storage. 6.3.5 Surface water resources associated with traprock land typ es The traprock areas offer potential for stock water storages with the greatest potential found on the more gentle slopes. Available clay construction material is often very limited in supply. Seepage losses can often be experienced from storages. Large irrigation storage sites are of limited availability, the main restrictions being the steep slopes in the hills and the lack of available bank height on the plains. 6.3.6 Surface water quality The surface water runoff across the area is generally of suitable quality for the irrigation of most crops and for stock watering purposes. Testing of the water quality for any proposed use is recommended. Water quality issues of concernare salinity, turbidity and agricultural chemicals. High levels of salinity can be harmful to irrigated crops, the soil, riverine aquatic life, as well as making the water unattractive for domestic use. High levels of turbidity cause difficulty in the treatment of water for domestic supplies and micro irrigation, as well as being detrimental to riverine aquatic life. Agricultural chemicals in water can be toxic to humans and animals who drink the water, as well as to riverine aquatic life. 6.4 Stream and catchment management 6.4.1 Stream management Activities within the stream environment are controlled under the Riverine Environment Protection Legislation. Any works which impact on the physical integrity of the stream require a permit from the Department of Natural Resources (DNR) Resource Management Group. River Improvement Trusts also undertake stream management works. 52 Water Resources 6.4.2 Catchment management A number of agencies and groups are involved in catchment management and include Department of Primary Industries (DPI), DNR, Border Rivers Catchment Coordinating Committee, Condamine River Catchment Coordinating Committee and Landcare. Water Advisory committees also exist in a number of areas. 6.4.3 Flooding andflo od plains Flooding occurs periodically and generally presents a hazard to the low lying flood plains along the streams and rivers. Recent major floods occurredin 1956, 1976 and 1988. The costs associated with the damage which can be caused by flooding has led to the construction of levees to protect cultivated land and property infrastructure. Levee banks require a licence from DNR Resource Management Group before construction. If the works are significant in terms of size, location or effect on flooding, a detailed study of the effects of the works on floodflows may be required before a licence can be issued. 53 54 7. Land Use 7.1 Introduction A variety of land uses occur in the Stanthorpe-Rosenthal region. The major land uses are: • cropping and pastures; • grazing sheep and wool, and beef production; • horticulture; • State Forests; • National Parks; and • apiculture. These are discussed in the following sections. Maps 4 and 5 show land cover for the region andare described below. On the granite country south of Dalveen, all agriculturally suitable land has been cleared and is predominantly used for horticultural purposes. However, a considerable amount of land in this area is non arable and agriculturally unproductive. Fortunately, most of the natural forest has largely been left intact. The Elevated granite plains in The Summitarea consist of gently to moderately sloping arable land. Here, most native vegetation has been cleared except on the isolated knolls (Granite hills land type) and along most roads. Inthe Undulating granite plains the flatto moderately sloping country has been extensively cleared andis used mainly for grazing. The steep narrow ridges, spurs and knolls where exposed rock is common, is natural woodland. The land use in the Storm King Dam area(Undulat ing granite plains) is mainly grazing. About 60% of this area, consisting of low to moderate slopes (occasionally up to 9%) , is extensively cleared. The very gently sloping country alongside the watercourses is totally cleared. Only the elevated hills and stony surface soils, with some large rock outcrops (Granite hills), still retain native vegetation cover. Of the Rolling granite mountains land type about 80% of the country is rough, steep, stony and rocky granitic highlandsunder native vegetation. Some clearing occurred in the narrow valleys and on plateaus. Some clearing has also been carried out for mining and wool production. The Granite hills to the west of Stanthorpe consist of steep, rocky ridges covered by native forest. The Granite rises - uniform sands land type has largely been cleared for commercial forestry, grazing and fruit growing. Some limited clearing for pasture production has occurred south of Wyberba. The remainder of the area is rugged woodland. The Traprock mountains in the JibbinbarMounta in, Rats Castle area are largelyuncleared and are of little agricultural value. 55 Land Use Inthe main traprock area, besides State Forest, Timber Reserves and extremely steep and rugged country, virtually all timber has been cleared with only a scattering of trees remaining. The same applies to the granitic areas south of Lesley Dam. The steep sandstone scarps and ridges, and slopes between 3% and 10 % in the Lesley Dam area are partly cleared. The Undulating sandstone rises in the Allan to Bony Mountain areaare cleared, except for some flat-topped sandstone ridges and scarps which have some tree and scrub vegetation left on them. The isolated traprock knolls which occur in this area are also extensively cleared. The Gently undulating sandy rises and some steep sandstone scarps and ridges in theLey bum area are under nativefore st except for some cleared paddocks. The creek flats and gently undulating sandstone plains in this unit are extensively cleared, as are the traprock protrusions, except for the upper hillslopes which are only partly cleared. Photo 7.1 Native pitted bluegrass (Bothriochloa decipiens) pastures on traprock soils, Emu Park, Texas 56 152° 28° Legend - Open Forest - Plantation Woodland Crops Grassland Built up area Shire Boundary Road - Dam (_____ � River/creek • ' Source Resource Sciences Centre data sets. Forestry tenure derived from the DCDB. Topographic data courtesy of AUSLIG. Accuracy Statement Due to varying sources of data sets, spatial lo cations may not coincide when overlayed. PART OF WARWICK SHIRE (PREVIOUSLY ROSENTHAL SHI RE) LAND COVER .A. : � Scale 1 250 000 0 5 10 km NAT u R A L IL__L__L__L__L__L__IL__IL__I_lL___lL__jJ RESOuRas Map 4 Legend - Open Forest - Plantation Woodland Crops Grassland Built up area Shire Boundary Road Dam River/creek Source Resource Sciences Centre data sets. Forestry tenure derived from the DCDB. Topographic data courtesy of AUSLIG. Accuracy Statement Due to varying sources of data sets, spatial locations may not coincide when overlayed. + STANTHORPE SHIRE LAND COVER Scale 1 : 300 000 0 5 10 km I I _l .J. J NATU RAL RESOURCES Map S Land Use 7.2 Cropping and pastures Ann Starasts 7.2.1 Introduction Most of the agricultural land in the Stanthorpe-Rosenthal region is used for grazing sheep and cattle. The soils are too shallow and light textured to store the moisture necessary to grow grain crops. Any cropping that is carried out in the area is for the purpose of growing forage crops, mainly for grazing. Broad scale cropping is restricted to the deep alluvial soils in the Rosenthal area around Wheatvale (Mixed basalt alluvial plains). Table 7.1 Indications fo r cropp ing in Stanthorpe and Rosenthal Shires 1992-93 Stanthorpe Rosenthal Hectares Yield t/ha Hectares Yield t/ha Total Agricultural Area 158528 164291 Area cropped 5901 3359 Area sown pastures 8305 5882 Lucerne for hay 16 1.9 492 5.9 Pastures for hay 18 1.8 570 5.7 Oats - forage 206 1473 Other cereals - forage 97 474 Forage sorghum - 247 Barley - grain - 345 2.4 Sorghum - grain - 174 2.6 Maize - grain - 65 1.2 Oats - grain - 78 Soybeans - grain - 30 1.3 Source: Australian Bureau of Statistics Farm size varies from hobby farms of around 50 to 60 ha, to grain/mixed farming and dairy properties of around 200 to 300 ha, to sheep/beef grazing properties of around 1200 to 4000 ha. 7.2.2 Crops Table 7.1 shows that less than 3% of the total agricultural area is usually cropped or cultivated. Much of this cropping is geared around providing feed for livestock by grazing, silage or grain feeding. 57 Land Use Forage oats is the main crop grown in the area. It is sown for winter grazing by cattle and to a lesser extent sheep. Lucerne and pastures for baling and grazing are also important in the area. Barley is the main winter cash grain crop sown for stockfeed and malting purposes. Summer crops sown include sorghum and maize for processing and increasingly, for silage. Irrigated cropping includes lucerneproduction, pasture and forage hay and some grain production, mainly on the alluvial soils along the Condamine River and on smaller areas on granite soils. Spray irrigation is the most common method of application. Minimum temperatures in winter are generally lower than in the main cropping areas on the Darling Downs. Winter crops, particularly on the lowest paddocks, are usually sown slightly later to avoid the high risk of frost damage. Due to the proximity to the Great Dividing Range, there can be a tendency for cloudy, showery weather conditions at times, which can increase the incidence of a number of leaf and stem diseases. These conditions may also extend the time needed for crops to dry down sufficiently to enable harvesting, which can put grain at greater risk of sprouting and quality damage. 7.2.3 Pastures Most pastures in the area are native pastures used for sheep and cattle production. Of the total agricultural area, approximately 4% is sown to improved pastures, most of which are comprised of clover-based pastures on the granite soils in the Stanthorpe area. Other pastures include lucerne-basedpastures on the alluvial and traprock soils. These pastures play a significant role in beef breeding and fattening enterprises, and to a lesser extent sheep breeding. Irrigated pastures other than lucerne are limited to small holdings on old orchards around Stan thorpe, and to a small number of holdings west of Warwick. They are usually based around annual ryegrasses and white clover andluce rne. The pastures are usually only irrigated through winter as water requirements to maintain them all year round aretoo high. The pastures are mainly spray irrigated, although there are a small number of holdings on traprock that are floodirrigated. 7.2.4 Land use on alluvial land typ es Mixed basalt alluvial plains - Pratten soils: Much of the cropping is performed on these fertile alluvial soils in the Wheatvale/Pratten area. Predominantly, this is because of the higher water holding capacity of these soils, higher fertility, good depth and the fact that they withstand cropping for long periods without a decline in the soil structure. Many of these soils have been cultivated for over 100 years, the smaller holdings 58 Land Use growing forage and grain crops in association with dairying in the early part of this century. A large range of summer and winter forage and grain crops are grown on these soils, including lucerne,barley, sorghum, maize and forage oats. An increasing area of crops are sown for silage and sold to feedlotters and dairies. Oats and some irrigated ryegrass are also sown for grazing dairy and beef herds. Lucerne is often grown in rotation with grain and forage/silage crops. Approximately 6 cuts per year can be expected from anirri gated lucerne crop. Yields vary from 12 to 20 t/ha (irrigated). These soils are fertilised with nitrogen for cereal crops and sulphur and zinc for most crops. The need for phosphorus fertilisers depends on soil test results in individual paddocks. Granite/traprock and traprock/sandstone alluvial plains - Rodger and Ley burn soils: Some areas of these soils are suitable for short-term cropping of one to two years. Crops mainly sown on these soils are lucerne andforage crops, such as oats or millet. Legume forage crops such as cowpeas, medic or vetch are also suitable for these soils, preferably in rotation with cereal crops such as oats or millet. These soils have moderate fertility, but they will require nitrogen fertilisers (for cereal crops and grass pastures) and phosphorus and sulphur fertilisers on all crops for good production. Pastures are often lucerne-based, and include a summer grass such as paspalum or rhodes grass. Other suitable species include the winter legumes/medics and white clover, and summer grasses such as Bambatsi, silk sorghum or purple pigeon grass. These pastures are usually sown from October to February, with February being the optimum time if sowing with temperate pastures such as medics and clovers. Stocking rates on improved pastures vary due to rainfall and nutrition of the paddock. Generally, with reasonable management of improved pastures, stocking rates should at least double that of native pastures. 7.2.5 Land use on granite land typ es Gently undulating plains and lower slopes with reasonable soil depth may be intermittently cropped (1 year in 5), prior to sowing to a longer term pasture, particularly when soil moisture conditions are good. They are often cultivated to grow a forage crop such as oats, millet, or cowpeas. These soils have low soil water holding capacity and will not withstandcontinued cultivation. They have low fertility, and require fertiliser or nitrogen buildup from legumes in order to grow a crop or reasonable pasture. Cereal forage crops such as oats or millet are fertilised with nitrogen, phosphorus and sulphur, and legume crops with phosphorus and sulphur fertilisers such as superphosphate. 59 Land Use Deeper soils could handle sudan grass sorghums, millets, cowpeas, or lucerne for a short term only (1 to 2 years). Those producers with irrigation will regularly grow oats, and often ryegrass for grazing or baling. Cultivation should be kept to a minimum on these soils, andif successive crops are grown they should include legume crops such as cowpeas or vetches. Some improvement of pastures does occur. The major advantage of improving the winter component of pastures is shown in the following comparison with native pasture (Table 7.2). Table 7.2 Seasonal percentage of total pasture production %of Total Sown Pasture Native pasture Production (Winter legume base) Spring 26 30 Summer 28 42 Autumn 23 25 Winter 23 3 Pastures suitable for the soils on the granite land types include: winter grasses rye and fescue winter legumes white clover, serradella and vetches summer grasses kikuyu, rhodes grass, premier digit grass, and paspalum. Pastures which are predominantly grasses require nitrogen fertiliser, and most mixed pastures require phosphorus and sulphur fertiliser. Pastures are usually sown into a fully prepared seedbed, although there is potential to establish some pastures by sod seeding into frosted native pastures or crop stubble. Where rainfall is greater than 800 mm per annum, and with at least 600 kg/ha of phosphate fertiliser applied over a period of time, the stocking rates of improved pastures can increase by 400% over native pastures. The deeper granite soils lend themselves to the growth of some fodder trees, among which Tagasaste or tree lucernehas proved effective. 7.2. 6 Land use on sandstone and traprock land types Allan, Dalveen, Karangi, Gammie, Glentanna, Maxland, Bonnie Doon, Drome, Mardon and Hanmer soils: Most of the sandstone and traprock land types are devoted entirely to grazing native pastures. Limited pasture development has occurred on the more friable sandstone soils (e.g. Mardon) and to some extent on the traprock soils. The soils suitable for pasture development have reasonable depth, are not hard setting, and have a reasonable water holding capacity. Even the better soil types are only 60 Land Use suitable for cultivation to sow pastures once in 7 to 10 years. Sod seeding improved species is the preferred method of pasture establishment. Cropping on these soils is restricted to small pockets of friable, deeper soils sown to forage oats, lucerne or pastures on grazing properties. Cultivation on these soils should be kept to an absolute minimum, therefore sowing crops or pastures into grass cover or crop stubble, using reduced tillage, is recommended. Forage millets, winter cereals, cowpeas and vetches are suitable for these soils, but cereals require nitrogen, phosphorus and sulphur fertiliser, while legumes require phosphorus and sulphur. Pastures recommended for these soils are included in Section 9.6. These soils should be cultivated no more than once every 10 years. Premier digit grass pastures have been shown to persist for up to 20 years on these soils if spelled adequately in summer to set seed. Withreasonable seasons and around 400 kg/ha of phosphate fertiliser applied over time, improved pastures can increase stocking rates by around 50 to 70%. Photo 7.2 Leftside of photo shows subclover and native grass pasture, Wo bur 61 LandUse 7. 3 Grazing 7.3.1 Sheep and wool Arthur Le Feuvre Sheep have been grazed throughoutthe Granite and Traprock region for more than a century and most land types are still used for sheep grazing. Merinos are the major breed. The most common sheep enterprise is wool growing using merino wethers; these being run on Gammie and Karangi soils. Self-replacing breeding flocks are maintained on more favoured soils such as the deeper Karangi, Leybum, Rodger and Pratten, and most of the granite-based soils where superphosphate has been used to establish improved pastures. It is possible that the development of improved pasture species and their correct management will see more breeding enterprises throughout the area. Meat sheep principally derived from British breeds (mainly Dorset, Poll Dorset and Suffolk), are bred for prime lamb production using improved pastures on fertilised granite-based soils (Cottonvale, Pozieres and Banca) or more fertile types (e.g. Rodger), sometimes with irrigation. Pastures: Pastures used for sheep and wool production are usually based on native species such as pitted bluegrass, Queensland bluegrass, wallaby grass, lovegrasses, spear/wiregrasses and kangaroo grass. Over the years burr medic has become naturalised in most pastures. On some soils, introduced species such as rhodes grass, creeping bluegrass, rye grass, paspalum, Johnson grass, white clover, snail medic, woolly pod vetch, subclover and numerous varieties of medics contribute significantly to pasture production and quality. Introductions are continuing and appear to offer considerable gains in animal production and soil improvement. The nutritive value of native pastures (andoften introduced species), usually falls significantly during the cold winters. Graziers usually respond by supplementary feeding of stock in an effort to reduce weight losses and tender wool. This feeding over some three months (July, August and September) aims to capitalise on likely early storms in October/November. If such storms do not eventuate, graziers face the difficult decision of continuing to feed or trying to sell stock on a falling market. Most choose to feed, which can cause considerable pasture degradation, leading to soil erosion when the storms finally arrive. The fact that many properties are too small to be viable (unable to run at least 4000 DSE), also entices the owners of these properties to try to keep stock 62 Land Use numbers up, in the face of pasture shortage, in an effort to pay off debt and/or have an income. Personal, resource and community damage may result. The practice of flat stocking, i.e. having some stock in most paddocks most of the time can cause major problems in improved pastures, particularly on the traprock soils. Palatable native and introduced species are soon depleted by such mismanagement and has unjustly given many useful species a bad name. Flat stocking and overgrazing has also contributed to the occurrence of significant areas of woody weeds and undesirable grasses such as the Aristida spp., the latter considerably downgrading wool values in many years through shive fault in fleeces. Sustainable sheep production over most of the area will demand grazing management practices other than flat stocking. Stocking rates: Stocking rates are highly variable. There is little doubt that the carrying capacity of a lot of properties has been severely compromised by long-term overstocking and the practice of flat stocking. The best traprock soils might carry 1.5 DSE/ha most years,but most areas carry much less (0.75 - 1.0 DSE/ha). Erosion, pasture degradation, woody weeds and sucker regrowth can easily halve the above figures. Wool production: Wool production per hectare per head is also highly variable. The biggest influenceis stocking rate and the previous stocking history of the country. In general terms, wool cuts on the traprock soils are around 4.0 - 4.5 kg/head, granite soils 4.0 - 5.5 kg/head, sandstone soils 4.0 - 5.0 kg/head and alluvial soils 4.5 - 6.0 kg/head. Lambing: Where breeding enterprises are carried out lambing percentages are around 75% - 110% depending on management and season. Merino lambs are usually grown out on native pasture, sometimes supplemented with fodder crop or grain. Crossbred lambs are mostly produced on fertilised, improved pastures on wetter granite soils, or grazing crops on alluvial and the more fertile soils. F eedlotting: Because of the proximity to grain supplies, feedlotting of lambs and adult sheep for meat production is likely to expand. Meat produced by feedlotting appears to have many of the features of grain fed beef, e.g. tenderness, hard white fat, good muscling and predictable eating qualities. Future change in the area's sheep industry will probably be driven by grower groups such as Traprock Wool Inc. This group is adopting ISO 9002 standards in wool production. Such a philosophy will initiate major changes in property management at all levels and will have significant impact on resource use and restoration. 63 Land Use 7.3.2 Beefproduction Geoff Strom Small, intensively managed beef herds predominate in the Stanthorpe-Rosenthal region. The average herd size is 150 head. Many herds are maintained to supplement income with sheep, and to a limited degree, crops and orchards. Breeding and selling slaughter cattle or producing stores for fattening are the main types of enterprises. However, significant numbers of stores are bought in for fattening. Most slaughter cattle are provided for the domestic market as well as some heavyweight grass-fed export requirements. Feedlotting: Feedlotting is a firmly established and expanding segment of fat cattle production. Current markets, both domestic and export, are increasingly issuing specifications which can only be supplied by intensively finished cattle. As these markets expand, intensive finishing of cattle will increase in importance. The demand to supply these cattle has already had an effect on the store market, and will bring further changes into this market. The increasing trend to finish cattle in intensive situations will decrease the numbers of cattle reaching the older ages now common, and will result in a gradual decline in the overall age of tum-off in the region. The use of developing techniques to increase reproductive rates anddecrease mortalities, will improve the economic prospects of producing store cattle in regions traditionally producing aged, fat stock. The downside is that intensive finishing is expensive, compared to low cost product from pasture. Intensive finishing is only feasible if the markets are prepared to consistently pay a commensurate price. Breeds: British breeds predominate, with quite a few small studs breeding pure animals. Hereford, Shorthorn and Angus would prevail with Charolais being popular. Most commercial properties run crosses of these breeds. Carcasses produced by these breeds meet the need of the major current markets, given appropriate nutritional levels. Pastures: Overall, most cattle are still bred or fattened on native pastures that are unimproved, although some 4000 tonnes of artificial fertiliser is applied each year. The areas of sown pastures, Stanthorpe 8305 ha (5.2%) of agricultural land and Rosenthal 5882 ha (3.5%) of agricultural land, are relatively small, but nevertheless do contribute to significant production. 64 Land Use Native pastures, which are unimproved, are essentially summer growing species which deteriorate rapidly in quality at the end of the growing season. Cattle grazing these pastures exhibit fluctuating growth patterns, and liveweight losses occur for about four to six months during the winter/spring periods. Stocking rates: Stanthorpe has 17 000 beef cattle held by 180 producers and Rosenthal has 29 000 beef cattle held by 124 producers. Of the available 164 29 1 ha of agricultural land in Rosenthal, approximately 86% is being used for some form of beef cattle production. Stanthorpe figures are 158 528 ha with approximately 81% used in beef cattle production. In both instances beef cattle are mostly combined with sheep production. The stocking rate varies widely with soil, rainfall and the extent of property development. On the highly improved pastures of the higher rainfall granite, 1 halAE is common, and this decreases to 2-8 halAE on unimproved traprock. Markets: Cattle are usually sold by one of three methods: a) private treaty of the property; b) public auction on liveweight or per head basis through saleyards; or c) on a weight and grade basis slaughter. Regular cattle sales are held in Stanthorpe and Warwick whilst significant abattoirs are close by. Costs: Surveys indicate that total farm costs (excluding interest and managers allowance), as a proportion of total farm returns,vary greatly depending on prices received for beef. Total farm cash receipts from beef enterprises in the Stanthorpe-Rosenthal region average 64%. Once deductions are made for the operators labour, therate of return to average capital and management varies from -1% to 11% depending on prices. Gross margins per adult equivalent equate to approximately $128 on the higher rainfall granite areas and $82 on the traprock areas. 65 Land Us e 7. 4 Horticulture Steve Tancred 7. 4.1 Introduction Horticulture in the Stanthorpe-Rosenthal region is based on deciduous tree, vine and fresh summer vegetable crops. Most fruit and vegetable crops are grown on the granite-based soils around Stanthorpe bounded by Lyra in the south, Dalveen in the north, Amiens in the west and Dalcouth in the east. There is some tree cropping on the traprock. 7. 4.2 History of development Apple trees and grape vines were first planted in the region in 1873 with production increasing markedly after the tin mining boom passed its peak in 1880. After the first World War and the establishment of Soldier Settlement Projects there was considerable development, especially to the north and west of Stanthorpe. However, most of these properties proved non-viable because they were too small or sited on poor soils. Many have now been amalgamated or planted to softwood forests. Transport of fresh fruit and vegetables to market is an important aspect of successful horticulture and this factor influencedthe location of early development. Areas close to main roads and railway stations developed first and have now been replanted several times to tree or vine crops. 7. 4.3 Soils The main horticultural soils are those developed on granite; namely, Banca, Cottonvale and Pozieres soils. All have a sandy surface horizon, poor fertility, are acid and low in organic matter. Because of the undulating landscape and local granite outcrops, there are localised drainage problems in many areas that need to be corrected before cropping. It is only because of the relatively high returns per hectare from horticulture, that the Granite Belt farmers can afford the high level of inputs required for successful cropping. The southernhalf of the district has a greater area of the better drained soils which are more suited to stone fruit and grapes during times of excessive rainfall and subsequent waterlogging. The northern part of the Granite Belt (e.g. Cotton vale, Amiens areas) contains some pockets of soil which are more loamy and support a higher intensity of production when waterlogging is not a problem. 7. 4.4 Climate It is the cold winters and cool summers that make horticulture economically feasible in the district, despite the soils being less suited to horticultural crops than most traditional fruit and vegetable areas. These mild-temperate conditions are a result of an elevation of 800 to 940 metres above sea level. 66 Land Use Stanthorpe experiences an average of over 60 frosts per year, which satisfies the winter chilling requirements of deciduous tree crops. Frosts in mid to late autumn and early spring limit the planting and harvesting of frost sensitive vegetables, and for this reason, site selection is important. Spring frosts can also damage the young shoots, flowers and small fruitlets of trees and vines. The selection of variety and planting site are very important, especially with stone fruit, as many new varieties flowerearly in spring. The risk of late frosts has limited the planting of trees and vines in low lying areas and immediately alongside the major watercourses of the Severn River, The Broadwater, Cannon Creek and Accommodation Creek. Temperatures are mild during the October to April growing season. During this period, temperatures range from average monthly minimums of 9-l5°C to maximums of 22-27°C, which suit many vegetable crops. Heatwaves are uncommon and cool temperatures at night are usual. Excessively hot, humid or wet weather conditions, which often occur in coastal horticultural districts at this time, can advantage Granite Belt vegetable producers as market shortages increase demand and prices. Stanthorpe's rainfall averages 770 mm per annum with nearly 70% falling in the growing season. This is adequate for dryland horticulture, but most modem intensive systems are based on irrigated production to overcome short-term deficits and provide for longer term droughts. Most trees and vines, and many vegetables (tomatoes, capsicums, cucurbits) are grown under trickle irrigation, as it is more efficient than overhead spraying. However, some tree crops have overhead irrigation to prevent damage from late frosts. There is local variation in the rainfall withDalveen in the north receiving 873 mm, Ballandean in the south receiving 760 mm, Amiens in the west receiving 775 mm and Eukey in the east receiving 825 mm per annum. The northern and eastern areas are closer to the eastern downfall of the Great Dividing Range where the extra rainfall occurs as drizzle accompanied by mist from the east. Hence, these areas are less suited to crops like grapes, some stone fruit and many vegetables that are prone to fungal or bacterial diseases. In fact, it is this easterly influencethat has limited development of orchards and vineyards on some areas with good horticultural soils to the east of the NSW/QLD border. Some Granite Belt vegetable producers have expanded into NSW to utilise existing water resources during drought years. Much of the summer rainfall occurs as thunderstorms and most properties have catchment dams to collect and store runoff for irrigation. 67 Land Us e 7.4.5 Irrigation water The local creeks and the Severn River are also used to harvest water for irrigation and on-farm storage; hence, development around these areas has been intensive. Underground water resources are limited, but many farms have developed wells and shallow bores to supplement supplies. Storm King Dam is the only major water storage in the district, but it is used only to supply Stanthorpe's water. A major irrigation dam is planned for The Broadwater which will supply areas from Applethorpe to Cottonvale and west to Pozieres. It is envisaged that this supply will be primarily as supplementary irrigation water, and not at a level which is required for fully-irrigated production. The trend towards more intensive production techniques, such as close planting, hail netting and fertigation, will be facilitated by the additional water availability. 7. 5 State Forests Peter Voller In the Stanthorpe-Rosenthal region, several forests are managed by the Queensland Department of Natural Resources (DNR). These are listed in Table 7.3. Although the principle objective in their management is the production of timber and associated products, watershed protection, soil and environmental conservation, and, where applicable, recreation, grazing, mining for minerals and bee-keeping are also an integral part of their management. Table 7.3 State Forests within the Stanthorpe-Rosenthal region Local Authority State Forest Number Area (ha) Soil Stanthorpe Passchendaele SF 263 4640 Banca* Stanthorpe Pozieres SF 32 1 186 Banca* Stanthorpe Broadwater SF 327 918 Banca* Stanthorpe, Durikai SF 444 12370 Gammie** Rosenthal, Karangi*** Inglewood Rosenthal Leyburn SF 574 2391 Gammie** Karangi*** Rosenthal Talgai SF 595 1402 Gammie** Karangi*** *Gritty, siliceous sands amongst rock outcrops **Shallow, gravelly loams ***Shallow, gravelly texture contrast soils In general, Native Forests in the area are not of high commercial value. This is due to slow growth rates and high levels of defects. 68 Land Use 3 Despite this, an annual harvest of 12 000 m of hardwood and cypress pine is cut from State Forests in the Stanthorpe-Rosenthal region. This timber is either cut as saw logs to supply local sawmills, or as poles or sleepers. Timber sales are made on the basis of an annual allocation basis which is closely monitored to ensure that the forest resource remains in a sustainable state. State Forest areas are also harvested for firewood sales on a regulated basis. The only commercial plantations in the area have been established on Passchendaele State Forest. These plantations are mainly the exotic pine, Pinus 3 radiata, and yield on average 1 Om /halyr of saw logs. The plantations cover an area of 1700 ha in the State Forest. The main markets for this wood are house framing and boards. Local sawmills in Tenterfield, Warwick and Killarney buy most of the plantation resource. 7. 6 National Parks Peter Hazelgrove There are two national parks and one conservation park in the Stanthorpe-Rosenthal region. They are Girraween National Park (12 000 ha) and HoransGorge Conservation Park (300 ha), both on granite, andSundown National Park (16 000 ha) on traprock, located to the east and west of the New England Highway respectively. These reserves occur at the southernend of the Stanthorpe-Rosenthal region; Girraween and Sundown both lying on the NSW /QLD border. Both parks feature elevated landscapes withrugged, although contrasting, topography. Girraween combines elevated flats and perched swamps with large granitetors, exposed slabs and steep gullies. Sundown is dominated by the Severn River which has down cut to produce a very steep, winding valley with rugged side gorges on the traprock. In addition, two granite intrusions, JibbinbarMountain and Mount Emily, and Red Rock Gorge add to the landscape variety. Horans Gorge is a steep sided valley, very similarto some of the western areas of Girraween. The vegetation in the parks is determined by soil type andclimate . Girraween is dominated by stringybark, blackbutt andyellow box forest with a complex understorey of heath species; pea bushes, wattles, banksias,hop bushes and other small wild flowers. Sundown, dominated by ironbark, box and cypress woodland, has a much simpler understorey of fewer, generally less showy species, mostly wattles, dead finish and peach bush. The exception is aroundthe granite intrusions where a heath vegetation similar to Girraween occurs. Some of the deeper gorges in Sundown contain significantpatches of dry vine thicket. Both parks contain rare and threatened species, particularly Girraween. 69 Land Use Macropods such as the easterngrey kangaroo, wallaroo and smaller red-necked and swamp wallabies occur in both parks. Platypuses are seen in the larger waterholes in Bald Rock Creek (Girraween) and the Severn River. A small colony of bush-tailed rock wallabies occurs in Sundown. The Superb lyrebird is found in all three parks and the regent honeyeater has been recorded in Sundown. It should be noted that despite the reasonably large area of landreserved and the very high number of species of plants in Girraween and Horans Gorge, many plant species and communities in the Stanthorpe-Rosenthal region only occur outside the park boundaries. Much of the vegetation in the area reserved is more closely related to the northernNew England area of NSW than those systems found further north. Therefore, reasonable preservation of floraand fauna will only be achieved with suitable off-park management. 7. 7 Apiculture Peter Warhurst 7. 7.1 Introduction Historically, the Stanthorpe-Rosenthal region has been one of Queensland's more important honey producing areas. However, the huge loss of honey florain this area is now of great concernto beekeepers. Outside the State Forests, production of honey from Caley's ironbark, mugga and brown box is rare. The most important honey, yellow box honey, is in great demand by the packers and consumers because of its superb flavour, light brown colour and non candying ability. Tumbledown gum and narrow leaved ironbark are also superior types of honey. Production of yellow box honey, together with other species in this area and from the Inglewood Shire, is now 7.5% of the total Queensland production. In 1973174 the figure was 46% of the Queensland production. This represents a production level of only 16% of that obtained in 1973174. Although still a major beekeeping area of Queensland many serious problems have arisen, including: • resource removal; and • access to honey and pollen plants. 7. 7.2 Resource removal Loss and removal of honey and pollen producing florais occurring at ever increasing rates. This is due to a number of factors: • chemical methods of tree removal have improved with the use of Picloram, Triclopyr, Hexazinone, Tebuthiuron, Glyphosate and 2,4-D amine either alone or in specific combinations; 70 Land Use • physical methods such as ring barking, pulling or dozing trees are all still employed; • costs to landholders have been reduced because of the taxation advantage of regrowth control; • numerous reserves under Crown control were released to freehold title to adjoining landholders. After this was completed most trees were removed; and • New England dieback combined with clearing for horticulture and the urban spread are reducing the areas of flora. 7. 7.3 Access to honey and pollen plants Where extensive clearing has occurred apiaries are not allocated as there is insufficient nectar or pollen to sustain the bees. Where clearing has not been as extensive, the number of useable apiary sites is proportional to the number of remaining larger trees useful to bees. Some areas set aside for National Parks are no longer accessible to beekeepers. Access to some properties where bees have been kept for many years is being denied to beekeepers. Two of the more common reasons given are: (i) that the bees pollinate the flowers; and (ii) bees carry the seeds over the property and cause more regrowth. The first point is partly correct because honey bees do pollinate eucalypt flowers. However, native bees, wasps, flies, beetles, ants, moths, butterflies, birds and some mammals are also responsible. Removing honey bees will not prevent the pollination of these flowers. The second point is incorrect and not possible, as bees do not carry seeds. Roadsides are commonly used by beekeepers, but many believe that access to these sites will also be lost. 7. 7. 4 Honey flora The tree species of major importance in the area to the honey industry, may be divided into four groups: • yellow box (Eucalyptus melliodora) and tumbledown gum (E. dealbata). These two species in combination are of prime importance in the study area. Their characteristics of reliability and high nectar output are highly valued; • grey box (E. microcarpa / E. mollucana), white box (E. albens) and Caley's ironbark (E. caleyi). These species are less important than the previous group, having a fair degree of reliability at moderate production levels; 71 Land Use • Blakely's red gum (E. blakelyi), mallee box (E. pilligaensis), silver leaved ironbark (E. melanophila), bluetop ironbark (E. fibrosa subsp. nubila), narrow leaved ironbark (E. crebra). These species are very important to beekeepers. Their production from season to season is very erratic but, during good seasons, they are very productive and beekeepers will move their hives to these areas. Mugga (E. sideroxylon) has been listed as important in the past, but has now been cleared to such an extent that it has no significant production; and • New England blackbutt (E. andrewsii), broad leaved stringybark (E. caliginosa), New England peppermint (E. nova-anglica), river red gum (E. camaldulensis). These are important support species, valued for their pollen production. The river red gum usually does not cause beekeepers to relocate hives, but it is of supplementary value in honey production areas. Shrubs are also valuable to beekeepers in the support role. Acacia spp., Dodonaea spp. and peach bush (Olearia elliptica) are important pollen sources. These are common throughout the region. Also of importance are commercial crops such as lucerne(Medicago sativa), maize (Zea mays), sunflowers and sorghum. In cultivated and otherwise disturbed areas, Mexican poppy (Argemone ochroleuca), mintweed (Salvia reflexa), turnip weed (Rapistrum rugosum), purple-top (Heliotropium amplexicaule) and carpet weed (Phyla nodiflora) can become useful sources of honey and/or pollen. 72 Land Use Further Reading For information on growing grain crops: Mills, W., Mcintyre, G. and Lucy, M. (eds) 1993, Darling Downs summer crop management notes, 1993-1994, Department of PrimaryIndustries South Region. For information on growing pastures and lucerne: DPI Farmnote 'Pastures for the Eastern GraniteBelt' Agdex 130-20. DPI Farmnote 'Pastures for the Traprock, Sandstone and Dry Granite Country' Agdex 130-20. DPI Farmnote 'Pastures for horses - Darling Downs' Agdex 130-20. DPI Farmnote 'LUCERNE cultivar and management recommendations 1995' F2. Cassidy, G.J. (ed.) 1988, Land Management Manual Shire of Inglewood, Cranbrook Press (Toowoomba) Pty. Ltd. Swann, I.F. (camp.) 1972, Stanthorpe Shire Handbook, Queensland Department of Primary Industries. Swann, I.F. (camp.) 1973, Rosenthal Shire Handbook, Queensland Department of Primary Industries. Wills, A.K. 1976, The Granite and Traprock Area of South East Queensland, Technical Bulletin No.13, Division of Land Utilisation, Queensland Department of Primary Industries. For fu rther information on Tagasaste: 'Tagasaste (tree lucerne) ' Agfact P2.1. 7 NSW Department of Agriculture; available from DPI Information Centres. 73 Land Use Photo 7.3 Vegetable production on Pozieres soil near Amiens Photo 7.4 Hail netting used fo r storms damage control on an orchard at The Summit 74 8. LAND DEGRADATION Ernst Heijnen 8.1 Introduction The amount, type and rate of land degradation varies according to the land resource, land use and land management practices adopted. Ifmanagement practices are aimed at using the soils according to their capability, then land degradation will be minimal. The main land degradation issues that occur in different parts of the area include: • loss of natural habitat; • soil erosion and siltation; • soil fertility, soil acidity and structure decline; • pasture rundown; and • weed infestation andregr owth. Other forms of landdegradation less significant in terms of area affected are: • wetness; • salinity; and • streambank degradation. 8.2 Loss of natural habitat When poorly-planned clearing of native vegetation occurs, not only does this result in loss of florabut also loss of fauna. Loss of insect eating birds andpredatory insects result in a build-up of pest populations affecting crops and pastures, and may be one of the causes of die-back of remaining trees. A suitable habitat for predatory birds and insects requires more than a monoculture.of eucalypt trees. An understorey of shrubby species is required to provide habitat for these predatory species. Unfortunately, many land managers do not realise the valuable function these shrubby species have, and tend to remove them as 'rubbish' even when they retain trees. It is important to have diversity of species in shade andnature corridors to maintain ecological balance (Voller & Molloy 1993). While planned clearing may be necessary in many situations to increase production, a lack of wind protection caused by total clearing may reduce productivity of crops andpastur es. Similarly, it has been noted that productivity losses occur when stock are subject to climatic extremes if there is not enough shade and shelter. This is particularly so when stock are already under stress from lactation, poor water supplies or they are below optimum weight levels. 75 LandDeg radation 8.3 Soil erosion and siltation Soil erosion, which occurs during summer storms, is a serious form of land degradation. The most common, but least noticed type is sheet erosion, with rill and gully erosion also occurring. The fine soil particles holding organic matter and nutrients are often removed from the paddock in the runoff water. This causes a decline in fertility, structure and water holding capacity of the remaining soil, and causes pollution downstream. The coarser, less fertile soil particles will settle out forming silt deposits. These silt deposits can occur further down the slope within the paddock, as well as some distance away from the eroding sites, depending on the intensity of the storm. Erosion and silt deposition can cause damage to pastures, crops, fencing, farm tracks, irrigation and drainage works, streams andpublic utilities, such as roads and railways. Silting reduces the capacity of streams, dams and waterways. It can contribute to more frequent and severe flooding. 8.3.1 Erosion of horticultural /and The horticultural lands of the Granite Belt are susceptible to water erosion due to runoffduri ng summer storms. Evidence of erosion of varying degrees of severity can be found over most of the area. However, the problem is most evident on land growing tree crops and grapes. Vegetable beds can also erode if provision is not made to control runoff water. The severity of erosion is particularly related to management practices, with degree of slope being a secondary influence. Management practices such as clean cultivation between rows on steep grades results in sheet and rill erosion, while gully erosion will occur where runoff water is allowed to concentrate. Uncontrolled runoffwa ter from steep land, rocky outcrops, road and railway culverts onto cropped land will cause severe damage. On the uphill slope of cropped land, distinct drops in soil surface levels of 30 ern or more from virgin country onto cultivated soil are common where unprotected land has been cropped for 20 years or more. Silt deposits of one metre or more are common on the bottom side of these paddocks. Washed out and damaged tracks are also a common occurrence. Although the area affected by silt deposition is small, the costs of damage repair and silt removal are high. Silt deposits are particularly detrimental to the growth and productivity of tree crops and grapes. Examples of damage repair involve the rebuilding of grape trellises buried by silt deposits. Where the practice of using scoops to redistribute silt deposits over the eroded area occurs, it is an indication that , land management practices are not adequate to reduce erosion to acceptable levels. 76 Land Degradation A soil erosion survey of a number of GraniteBelt properties by Wills (1980) found a net loss of production in many vineyards and orchards due to soil movement. In eroded areas, soil and nutrients were depleted; while in depositional areas, increased foliargrowth competed with fruit development which affected yield and ripening. Individualpaddocks on three properties were studied in detail to obtain quantitative data on soil loss rates. Estimates showed net loss varied between one and seven tonnes of soil per hectare per annum. Movement of soil within paddocks was estimated to be between 20 and 41 tonnes per hectareper annum which is considered to be more relevant to production variation than the net loss figure. Soil erosion problems and their causes in other horticultural areas of theregion, such as the sandstone areas south and west of Warwick, are similarto those of the Granite Belt. Here the annual rainfall is lower, but the high intensity summer storms on cleanly cultivated soils can cause significant damage. In the few orchards on the traprock, cultivation is not practiced because of lack of soil depth. Orchards are irrigated and weed control is carried out with herbicides. Consequently, there is minimal damage from soil erosion. 8.3.2 Managing soil erosion in horticultural land Soil erosion control measures in horticultural land include: • mechanical measures to control runon and overland waterflow; • mechanicalmeasures to control water in the cropped area and to increase infiltration; and • conservation cropping practices. Mechanical measures to control runon and overland water flow Diversion banks, head ditches and waterways: Diversion banks are needed to intercept runoff entering cropping landfr om road and railway culverts, and from rocky or other landabove the cropped area. They are designed to handlethe amount of runofffr om the particular areas involved and are surveyed on a low enough grade to prevent channels from washing out (approximately 0.5%). If steeper grades are used to match the farm layout, then the channel may need to be stabilised with grass to prevent gullying. Head ditches are used aroundthe edges of blocks for control of small amounts of runoff(catchments up to 2 ha). It is advisable to construct them with a flat bottom, rather than v-shaped, to prevent erosion of the channel. It is preferable that stable, well-grassed, natural watercourses be used to carry discharge water. Where natural watercourses are not available, waterways need to be constructed and grassed to an adequate design standard to prevent gullying. These waterways may need to takethe disc harge water from diversion banks, head ditches, road and railway culverts, internal contour banks or drains, and individual rows. 77 LandDeg radation Waterways should be constructed so that tractors and machinery can cross them to allow the full width of a paddock to be worked. When crossing waterways with tillage implements, the implements should be lifted so the grass lining of the channel is not damaged. The waterway channel should be deeper than the channel of adj acent structures so water from these structures can flow freely into the waterway channel. Diversion banks andwaterways are designed to handle the runoff water from a one in ten year frequency storm. Diversion bank channels should be allowed to grass naturally or they can be planted with suitable grass species. Waterways should be planted to the recommended grass as soon as possible after construction and should not be used to carrywater from structures until they are grassed and stable. Their stability depends on maintaining a complete vegetative cover. Mechanical measures to control water in the cropped area and to increase infiltration Wa terways: The information provided above on waterways applies. One directional cultivation: In established cultivated orchards with squareplant pattern s, some reduction in erosion can be achieved by working in one direction only. The direction adopted will depend on achieving the most satisfactory slope along the direction of cultivation. To adopt cross-slope cultivation it may be necessary to establish a series of small waterways in hollows. The rows can then be slightly hilled so that each row handles its own water at a reduced velocity. At theends of rows any water running out is then able to be controlled safely. In some situations adjoining grasslandcan be used to safelyspread water from thero ws. Even though the slope down some rows may still be steeper than desirable, the system is a compromise during the remaining lifetime of the orchard. When the orchard is replanted, a properly planned system should be implemented. Contour banks: During the early years of soil conservation in orchards, graded contour banks were sometimes installed at intervals through existing tree crops. This required the removal of a number of trees on each line, which was a sacrifice not easily made. New plantings were made between contour banks withrows running parallel to the banks. As contour banks themselves seldom run parallel to one another, this system often resulted in one or more short rows in the middle between two banks, or varying widths between rows. Runoff flowingacro ss rows was intercepted by the contour banks before it was able to be concentrated into rills. The direction of cultivation was parallelwith the contour bank. Contour banks are also used to protect vegetable crops. The banks are installed at intervals down theslope, then the beds are formed parallel to the banks. The resultant depressions between beds provide further drainage for individual rows. 78 Land Degradation Contour banks can be used for access, with the tracks either on the banks or adjacent to them. To ensure that pondage does not occur in either orchards or vegetable crops, a grade of around 1% is used for contour banks. They are constructed from the top side using a crawler or farm tractor fitted with a dozer blade, or a grader. Bank channels should be grassed-up to reduce gullying. Mounds and beds: Mounds and beds are raised plant areas. They provide extra depth of topsoil for better root development, extra available moisture holding capacity andnutrie nts, and better drainage. Mounds and beds can be constructed to intercept and direct runoff flowsto control soil erosion. Inpome and stone fruit orchards with widely spaced tree rows (e.g. 4-5 m) mounds consist of small narrow banks. At the establishment stage of the orchard, before planting, a small narrow bank to a height of 45-60 em is constructed on each row location. Every third row is surveyed on a set grade. The two rows in between are measured to divide the space evenly. Because of slope differences alongthe lines, slight variations in width between rows occur. The bankscan be constructed and allowed to settle before planting, otherwise trees are planted 10 to 15 em deeper than normal to allow for settlement. The space between the banks is cultivated. In this system each row handlesits own runoff waterand drains into a subsurface waterway. Providing that waterways are deep enough, and all bank outlets are clear, a slope of 0.5% along rows is sufficient. However, 0.5% is regardedas an absolute minimum. A higher grade of 1% or more is preferred by most growers, especially if internal soil drainage is poor. Ponding of water along rows for any length of time is detrimental to crops. In longrows of 150 metres or more, grades towards the outlet end of banks have to be kept down to about 1% to prevent too high a flowvelo city and scouring. In more modem close planted orchard layouts the same principles as above apply. Mounds consist of closely spaced broad based banks. The space between mounds is a channel. It becomes an alternating system of broad banks and channels. Ifthe inter row space is to be cultivated, the rows must be on a suitable grade across the slope (around 1%). Every fifth row may be surveyed, and the intermediate four rows measured in. Continuous vegetable beds of any lengthmust be on a suitable grade across the slope (around 1%) to prevent erosion. The depressions between beds provide for drainage emptying into subsurface waterways. Parallel contour layouts: Where the topography is even and slopes do not vary greatly, parallel contour layouts are a possibility. It is preferable that mounds andbeds, and inter-row spaces are of constantwidth to simplify cropping activities. To develop a plan for such a parallel system it is important that a contour survey is carried out. If rows are kept 79 LandDeg radation short, by incorporating one or more extra waterways, there is a better chance of success. Key lines need to be surveyed on predetermined grades to which adj acent beds or mounds are made parallel. Grades will vary in a parallel system. A steep grade of 3-4%, over a short distance (50 m), at the beginning of a channel is acceptable because in this situation it is carrying a minimal flow. Depending on soil type and bank/row length, lower grades of 0.5-1% are required to ensure channels do not erode. Straight and parallel rows: Especially in vineyards, but also in trellised tree crops, it is of great advantage if rows are not only parallel to each other, but also straight. It is difficult and more expensive to build trellises on curved lines. The same principles as discussed in the previous sections apply in planninga straight andparallel layout, as the aims are the same. Each row must handleits own water at safe velocities. Straight and parallel rows may makemechanical harvesting more efficient. Bench terraces: Bench terracing has been used on occasions in both tree and vine crops, but they have a disadvantage on steep slopes, where harvestingthe bottom side of rows becomes a problem. Again, each terracemust handle its own water at safe velocities and drain into subsurface waterways. To construct them, cuts and fills aremade using a grader. Deep ripping: Deep ripping of Banca, Pozieres and Cotton vale soils before plantingcrop s, especially long-termhorticu ltural crops, is recommended if a hardpan is present in the soil profile. Hardpans restrict root development and reduce productivity. A hardpan may be a natural occurrence, it may be caused by intensive traffic in wet weather, or by cultivation such as repeated discing and rotary hoeing at shallow depths which can allow hardpan development below cultivation depth. Breaking up the hardpan will improve internal drainage and root development, and in combination with other soil conservation measures increase infiltration, resulting in less runoffand ero sion. In existing orchards and vineyards, deep ripping is not recommended as it would do too much damage to established root systems. In small cropping paddocks, deep chisel ploughing may be carried outif necessary, at the start of a fallow to loosen compacted soil. Conservation cropping practices Sod culture: Sod culture is the growing of permanent grass or a grass/legume mixture e.g. fescue and clover, as ground cover in orchards. Sod culture is a zero till conservation cropping system. It is the preferred system, from the conservation point of view, as it provides excellent protection against erosion andimpr oves or maintains the physical condition of the soil. However, the grass and legumes compete with the trees for moisture and nutrients. Ample irrigation water must be available for sod culture to be feasible. When changing over from clean cultivation to sod culture, 80 Land Degradation extra nutrients must be added. Regular mowing and allowing the grass cuttings to decay, results in increased organic matter content of the soil and gradually makes up for the initial nutrient loss. With a complete ground cover, rows can run up and down the slope without causing serious erosion. However, with trees on mounds across the slope, better use is made of rainfall as water has more time to soak into the soil. Mounds can be kept bare with herbicides restricting the sod cover to the inter row space. This reduces the competition from the sod. To enhance infiltration and control erosion within the row, a straw mulch may be needed if rows are on a grade steeper than 3%. Reduced tillage: Frequent clean cultivation destroys soil structure and does not conserve soil moisture. With reduced tillage in orchards and vineyards, weeds are allowed to grow for a while before they are ploughed out. When chisel points with sweeps are used, the weeds are mulched on the surface. Slashing is often necessary before working when weed growth has become too tall. The mulch on the surface provides protection from erosion by reducing raindrop splash, increasing infiltration and slowing runoff flows. It also reduces evaporation and is a source of soil organic matter. Cover cropping: Cover cropping further reduces the need for cultivation, provides protection from erosion and increases the organic matter content of the soil when ploughed under or mulched. As fruit trees andvines grown in the area are inactive during winter, their requirements for moisture andnutrients areminimal at this time of theyear. It is for this reason that cover cropping is carried out during winter. Oats are planted between February and April when production is finished, then ploughed under or sprayed out andmulched during August. Zero tillage: The best zero tillage practice in orchardsis sod culture as described previously. In vineyards sod culture may need to be used when rows must run up anddown the slope, for example, on small parcels of land between rocky outcrops, or where there is a shallow surface layer and poor drainage. The rows themselves need to be kept clean for maximum production and prevention of frost damage in winter. Zero tillage in vineyards amounts to complete chemical weed control. Non disturbance of the soil is beneficial to crop growth,especially in shallowsoil s. In orchards where insufficient irrigation water is availableto allow for sod culture, especially when row spacing is narrow, zero tillage by complete chemical weed control is worthy of consideration. 8.3.3 Erosion of alluvial cropping land The Condarnine River flatsare subject to occasional, severe erosive flooding. This area is almost entirely cultivated for the production of grain, grazing crops and 81 Land Degradation irrigated pastures for the dairy industry, because of generally high fertility soils with high moisture holding capacity. Large amounts of soil have been lost during deep, fast moving floods,especially from depressed areas. As the soils are deep, the area is generally still productive if fertility is maintained. The river flats of the SevernRiver (dark brown gradational soils) and the creek flats of Rodger (Rodger soil), Greymare, Thane, Back, Canal, Sandy and other smaller creeks and large watercourses (Leyburn soil) are also subject to occasional erosive flooding. The risk of damage is high on the most prone areas when they are in a loose, cultivated state. Some of these flats have suffered severe flood erosion. Badly eroded paddocks are no longer suitable for cropping, as the fertile top layer of soil has been lost, and workability and physical properties of the remaining soil are severely limiting. 8.3.4 Managing soil erosion in alluvial cropp ing land The cropping areas on much of the Condarnine River alluvium are not ideally suited to strip cropping because of uneven land surface and the resulting irregular shape of contours. Floods moving across some of the area canbe deep and fast moving. Strip cropping is not effective under these conditions. However, areas where contours are sufficiently even to allow a practical layout to be implemented should benefitfr om this practice. Land use andland management adjustments need to be made when strip cropping is adopted, but it canbe designed to suit the enterprise. Depressed areas of high erosion potential arebest retired to permanentpasture . Zero tillage anduse of a rotational ley pasture system will further reduce risk of those areas that are cropped. The cropping lands on the other alluvial soils of the area, such as Rodger and Leyburn, are also unsuitable for strip cropping as areas are narrow, have uneven contours, and the velocity of floodwaters can be high. As these soils are only marginally suitable for cropping they may never fully recover after an erosion event. Zero till would decrease the erosion risk and is worth considering on well-structured soils, but as eroded soil surfaces are usually hard setting, it would be difficult. Growing of improved pastures including lucerne, with a minimum of cultivation, is the recommended maximum land use for these areas. 8.3.5 Erosion of grazing and occasionally cultivated land Traprock soils: Limited cultivation has been carried out on the better soils in the traprock country to grow fodder crops, with the emphasis on winter crops such as oats. As the topsoil is shallow andslopes range from 2-5%, soil erosion can occur. None of the traprock soils are suitable for lengthy periods of cultivation and need to be rotated back to pasture for lengthy periods. Cultivated areas on creek flats subject to flooding, have been badly damaged by flooder osion. The texture contrast alluvial soils of the traprock country do not recover once the topsoil is eroded, and ectedaff areas can become scalded and vulnerable to further wind and water erosion. 82 Land Degradation On the permanent pasture country, soil erosion has occurred where plant cover has been removed due to grazing pressure, exposing the soil surface to erosion by water. Sheet erosion occurs extensively where plant cover is low, with some gully erosion occurring in natural depressions and on side slopes into depressions. Because of the shallow topsoil even minor soil losses markedly reduce the productivity of these traprock soils. The land surface tends to become scalded and hard setting even after small amounts of topsoil have been removed. Wind erosion can also occur to a minordegree. The practice of timber clearing by pulling and burning, combined with regrowth control by 'sucker-bashing' the area with sheep, leaves the ground surface bare and vulnerable to water and wind erosion. Photo 8.1 Sheet erosion on undulating to rolling traprock hills 83 LandDeg radation Sandstone soils: The arable land (e.g. Mardon soil) of the sandstone scrub country was intensively cultivated for fodder crop production, 20 or more years ago. The steep undulating topography and the farming practices of thattime were the main contributing factors to severe sheet andrill erosion, with gullying in the hollows. Erosion during those early years left the country degraded, and although a lot of soil conservation earthworks were carried out, most of the land was returned tonative or improved pastures. Some minor areas are still occasionally cropped, mainly for fodder crops, before rotating back to pastures. Of the sandstone forest country, the arable land (e.g. Dalveen andAllan soils) that is cultivated is used to grow fodder crops on an intermittent basis, before sowing to improved pasture. Water erosion can occur and earthworks have been constructed over much of the area. On the open grass country, all sandstone soils are subject to water and, to a lesser extent wind erosion, during periods of severe overgrazing. Eroded gullies in the hollows andwaterc ourses are common. On the gently undulating sandstone plains some of the Maxland soils have been cultivated in the past. Water andsome areas of wind erosion were extensive, leading to the abandonment of cultivation and establishment of improved pastures. Some of the better paddocks were contoured and are still intermittently cultivated for winter grazing crop production. The occasional paddocks on deep sand (Drome soils) in this unit were cleared and cultivated. Erosion andresulting siltation caused by high intensity rain has been very serious on some of these paddocks. The loose sandis also susceptible to wind erosion if areas areextensively clearedof protective vegetation without leaving shadelines. Granitic soils: Serious soil erosion has occurred on granite soils where they have been cultivated for the production of fodder crops. Improved pastures were established after generally short periods of cultivation. Many paddocks were contour banked after erosion problems became evident to provide protection during the pasture establishment phase. Some cropping is still practiced. Water readily runs off the loose sandy soil surface when cultivated, making them susceptible to sheet, rill and gully erosion. On the texture contrast soils (Greymare and Lyra soils) the subsoils arevery erodible and dispersible where sodium levels are high. Deep gullying and some tunnel erosion occur in many hollows and watercourses. Open grasslandis subjected to water and minor wind erosion when overgrazed. 8.3. 6 Managing soil erosion in grazing and occasionally cultivated land Cultivated areas: To minimise soil erosion in any cultivated area it is importantto use a combination of structures and conservation tillage practices. Structures such as diversion banks, contour banks and waterways, are used to shorten overland flows andcontrol concentrated flows. Conservation tillage practices such as contour cultivation, 84 Land Degradation rough tillage, minimum tillage and stubble mulching, should be used in conjunction with earthworks to reduce erosion to acceptable levels. Soil conservation structures: Conservation structures, such as diversion banks and contour banks, can be used on most of the arable soils on sloping land. Exceptions are the texture contrast soils with shallow surface horizons (less than 30 em deep) and dispersible subsoils, such as some of the Lyra, Maxland and Karangi soils. Excavating into dispersible subsoils can result in tunnel erosion starting in the bank channel and eroding under the bank. Ifthese soils with dispersible subsoils are on slopes greater than 2%, they should not be cultivated as they can not be protected by earthworks, due to the risk of tunnel erosion. However, on low slopes (less than 2%) contour cultivation combined with grass strips can be used, provided that natural grassed drainage lines and watercourses are left undisturbed. Contour banks should be on a suitable grade (e.g. 0.2%) to avoid potential waterlogging and salinity problems on low grades. Ifbank grades are too steep, then the bank channel may erode. It is preferable to use grassed, stable, natural depressions to carry water from contour banks. Where waterways are used, it is preferable they consist of a wide grass strip up and down the slope on natural ground level. The traprock, sandstone and granite soils often have shallow surface horizons, erodible subsoils and low fertility. If waterways are constructed on these soils and the subsoil is exposed, gully erosion can occur. Waterways should not be built on these soils, but if this is unavoidable, then topsoil should be replaced. Where waterways need to be built in perched situations (e.g. a site with side slope) where a channel with only one bank on the lower side is needed, some or all of the topsoil can be pushed or graded to the top side of the channel first, the channel excavated and the bank constructed out of subsoil. Mter completion the stockpiled topsoil can be spread back evenly over the width of the channel. A minimum of 10 em depth of topsoil is required so that a good grass cover canbe re-established. Where waterways are being built on sites without side slope, retaining banks on either side arerequir ed. These can be constructed from the outside so as not to disturb the grass strip between the banks. Contour banksdischarging into the waterway, at intervals down the slope, intercept any waterflow down the outside excavation of the waterway banks. Conservation tillageprac tices: Tillage producing a rough, cloddy surface is achievable on most soils with the exception of the loose coarse sands of the Banca, Pozieres and Drome soils. A rough cloddy surface allows better infiltration and reduces overland flow velocities, resulting in less erosion. A rough soil surface is also more resistant to wind erosion. Chisel ploughs do less damage to the soil structure and they can produce and maintain a rougher surface compared to disc implements. After the first working with chisel points, sweeps may then be fitted to obtain better weed control. Low profile sweeps cause minimal disturbance of the soil by passing underneath the surface leaving the clods largely in tact and on top. Reducing thenumber of 85 LandDeg radation workings also maintains a rough surface for a longer period, and any protective trash will last longer. Ifthe feed situation allows, it is advisable not to graze crops right down so the residue can provide some cover during the fallow period. Spraying for weed control may replace one or more workings. After the final grazing of oats, the fallow period coincides with the summer months when erosion damage fromhigh intensity storms is most likely. The maintenance of a rough soil surface, combined with as much cover as possible during this critical time, will reduce soil erosion. It will also result in better moisture storage which will be of benefit to the next crop. Pasturecountry: Special management measures, aimed at restoring and maintaining an adequate ground cover of greater than 30%, may be needed to prevent degradation and to rehabilitate degraded areas. These measures include fencing to control grazing, relocation of watering points, ripping, chisel ploughing andre-seedi ng. The principle soil erosion control measure in pasture country is the maintenance of adequate ground cover. Adequate ground cover ensures that soil infiltration rates are maintained, overland flowvelocities are reduced when runoffdoes occur, and the risk of erosion is minimised. It has been shown that a pasture cover above 40% reduces runoff and soil loss significantly in grazing lands (Silbum et al. 1992). The adoption of safe, flexible stocking rates is the key to maintaining a good pasture cover. The grazing system that is used can have a significantimpact on the combination and persistence of pasture species present, that is, the quality of the pasture. Obviously the issues of pasture quality and quantity are interlinked and grazing management must affect both. For more information refer to the discussion on 'Pasture Rundown' (see Section 8.5). Safe stocking rates will vary throughout a property. Different areas will have different production potential and erosion risk. It is important to develop a property management plan which recognises these differences. Where practical, fencing should be located to separate the different land classes and produce a sufficient number of paddocks to enable rotational spelling of pastures. Critical areas such as actively eroding watercourses and creeks should be fenced to restrict grazing by livestock, thereby enabling stabilisation. In developing a property management plan, thelocation of 'high use' areas such as roads, tracks, laneways, gates and watering points should be given careful consideration. The plan may also identify areas to be left under timber or set aside for timber regeneration. Windbreaks reduce the risk of wind erosion and provide stock with shade and shelter. The property plan should aim to encourage even grazing pressure through strategic location of watering points and tree clumps. During drought, areas of low erosion risk could be fenced off into holding paddocks. Stock canbe kept and fed in these areas to prevent all paddocks from being grazed out to allow for quick recovery of pastures when drought breaking rains occur. 86 Land Degradation Practices aimed at increasing ground cover to combat water erosion will also combat wind erosion. For example, roughening the ground surface to increase water penetration also reduces the risk of wind erosion, as a rough cloddy surface is more resistant to soil loss than a smooth one. To control erosion in hollows and watercourses it is sometimes necessary to strategically poison trees to increase grass growth. Problem areas should be fenced off temporarily, and stabilisation work undertaken on active gullies within them. Stabilisation measures include battering and grassing of gully heads and overfalls, grassing of gully floors andwhere warranted, chute and drop structures of different types and materials. Refer to the local Land Conservation Adviser for information on the design and use of thesestructur es. Water spreading canbe very beneficial as an aid to gully control. Instead of allowing water to concentrate in depressions, small diversion banks or drains canbe installed to spread runoff water onto broad slopes or ridges where it can increase pasture growth. 8.4 Soil fertility, soil acidity and structure decline 8.4.1 Granite soils The loose, gritty, siliceous sandy soils (Banca and Pozieres) are poorly structured, acid soils of very low fertility. With cultivation they become more infertile and structure deteriorates further. Water does not easily penetrate the soil surface because of its water repellent properties. Cultivation aggravates these problems due to the loss of organic matter. Higher runoffresults in more soil erosion. Sod culture under fruit trees, where sufficientirrigation water is available, is the preferred system to reduce problems with soil structure. The extra growth of medic and clover-based pastures, using phosphate fertilisers, has increased soil acidity. As pastures become affected by acidity, sedges invade and pasture productivity is reduced. Application of lime or dolomite to increase pH, together with the application of fowl manure or sawdust to increase organic matter, is a common practice in horticultural areas. The increase in organic matter results in an increase in both water absorption and water holding capacity. The loamy sands,sandy loams andlight sandy clay loams of the yellow and grey mottled, texture contrast soils (Cottonvale soils) are weakly structured, infertile and acid. They arevery friable when in good condition. The friable structure is soon lost through compaction by grazing or cultivation, and through loss of organic matter. The soil becomes hard setting, resulting in lower infiltration of rainwater, high runoff and erosion. Intensive use of inorganic fertilisers increases acidity. The problems and causes of fertility and structural decline of the Greymare and Lyra soils are similar to that of the Cotton vale soil. 87 LandDeg radation 8.4.2 Traprock soils The shallow gravelly loams (Gammie soils) vary considerably in initial fertility (low to high) because of variability in parent material. The fertility of the shallow to moderately deep, gravelly texture contrast soil (Karangi) is low to medium while that of the Glentanna soil is medium to high. Even the fertility of some of the better minor soils declines rapidly when used for continuous grazing, without any inputs. The initial fertility of these arable soils declines rapidly when cultivated and cropped. The Gammie, Karangi and Glentanna soils are generally massive, hard setting soils. Those that arenot, have a fragile surface soil structure. Intensive grazing or cultivation quickly causes structural breakdown. The soil surface will set hard, has reduced infiltration and increased runoff, and the resultant soil erosion causes further degradation. The remaining soil surface tends to become scalded even after small amounts of topsoil have been lost by erosion. The brown structured earths, a minor soil of the Elevated low traprock hills land type, is deep, moderately fertile and more stable than the other soils. 8.4.3 Sandstone soils The fertility of the sandstone soils is generally low. Even on the better soils, the initial fertility soon deteriorates through cropping or heavy grazing. The moderately acid Dalveen and Maxland soils become more acid with the use of fertilisers and will need lime to correct the problem. The very acid Hanmer, Bonnie Doon and Drome soils need lime if cropped. The Mardon and some of the Allansoils are the more fertile of the sandstone derived soils in the area. However, fertility decline with cropping, and the resultant soil loss are serious problems. The Hanmer andMaxland soils are hard setting while the Dalveen, Allan and Bonnie Doon soils usually become hard setting if not carefully managed. Cultivation resulting in rapid loss of soil organic matter and/or trampling of stock when wet, makes thehard setting characteristics more strongly developed. The sandy Drome soil breaks down to single grains and becomes more subject to erosion by water and wind with the loss of organic matter. 8.4.4 Alluvial soils The deep, self-mulching, black, cracking, Condamine alluvial soil (Pratten) has high initial fertility. However, in areas wherethere has been heavy soil losses caused by severe erosive flooding, the result has been a serious decline in productivity. This decline in productivity results from the contact of plant roots with subsoils with high sodicity and alkalinity levels, and a coarse structure and hardconsistence, compared with the topsoil. 88 LandDeg radation The initial fertility of the Rodger soil is medium andLeybum soil is low. Acidification occurs due to the increase in organic matter content of the surface soil as a result of fertiliser andnitrogen producing legumes. Lime or dolomite may be used to correct this problem. Without fertilisers the fertility declines fairly quickly under cropping. The Leyburnand Rodger soils generallyhave hard setting surfaces. The hardsetting characteristics become more strongly developed with cultivation and loss of soil organicmatter, therefore restricting their suitability for cropping. Trampling by stock when wet has the same detrimental affect (compacts the surface). Soil erosion caused by flooding is extremely detrimental for both the fertility and structure of these soils. 8.4.5 Managing soil fe rtility, soil acidity and structure decline The quickest way of losing soil fertility and structure is through the loss of topsoil by erosion. Control measures to prevent soil fertility and structure decline include all the measures to minimise erosion discussed in the soil erosion section. Fertility management aims at maintaining soil organic matter, structure, nutrient status and a desirable pH. This is obtained through the use of fertilisers and amendments together with crop rotations including pasture phases and reduced tillage. Maintenance of pH at desirable levels is necessary as soil nutrient availability is affected. Some elements, such as aluminium, can become toxic at low pH. In the horticultural areas, the addition of organic matter in the form of fowl manure or sawdust, and the application of lime or dolomite to increase pH, is a common practice. Soil and plantana lysis allows fertiliser application to be optimised, thereby ensuring maximum use of the applied nutrients by crops and pastures. Reducing tillage frequency, and restricting tillage and stocktramp ling during wet conditions, reduces soil compaction. Allowing swelling clay soils (Pratten) to dry out and crack canam eliorate compaction. 8.5 Pasture rundown Whilst soil erosion, soil fertility, pH and soil structure decline contribute to pasture rundown, inappropriate grazing managementis the maj or cause of declining pasture condition. Regrowth following clearing, associated with overgrazing, is also a prime cause of pasture rundown. Poorly managed grazing systems tend to result in the more palatable pasture species being grazed more heavily than the less palatable species. This creates a situation where the less desirable species, such as wire grasses, have more chance to set seed, and eventually these plants dominate. The problem is widespread in the area, with 89 Land Degradation rundown pastures often providing less ground cover, resulting in further soil erosion. As production levels decrease, then pasture quality also deteriorates. Tothill and Gillies (1992) estimated that 60% of the Bothriochloa and Stipa pastures of the traprock country had deteriorated to an extent where management changes were required to restore them to an acceptable level. Additionally, 15% of the traprock and 10% of the graniteand sandstone pastures had degraded to such an extent that irreversible changehad occurred. 8.5.1 Managing pasture rundown The management of pastures involves developing an understanding of what species are present andhow the grazing system is affecting the pasture condition. Regularly monitoring the pasture composition and the extent of ground cover will give information as to how the composition is changing over time. Ifthe grazing value of different plants in a pasture is known, then pasture condition may be improved by changing grazing management and by adopting safe, flexible stocking rates. It is important to note that the process of using management to change pasture composition back to the more favourable species, once it has degraded, is difficult and long-term. It is a far better option to monitor pastures so that managementcan be altered as soon as signs of degradation are detected. Measures to control soil erosion, soil fertility andstructural decline are fundamental in maintaining dense, productive pastures and keeping weeds out. Weeds, including unpalatable grasses, woody weeds and regrowth all compete withuseful pasture plants for moisture and nutrients, and should be controlled. Fire is one of the few management options available to producers in extensive rangelandsto control weed species. Used opportunistically and intelligently, it can be a very useful tool. Spelling pastures during the growing season encourages seeding, but some knowledge of the growth pattern of the favoured species is needed for definite recommendations. Improved pastures should be fenced off separately from native pastures. They are more sensitive than the native pastures to heavy grazing pressure, so theirgrazing should be more carefully controlled. Many of the soils in the area (Gammie, Karangi, Glentanna, Hanmer, Maxland, Leybum and Rodger) are naturally hard setting and with bare soil surfaces water infiltration is inhibited, and they do not easily regenerate. Other soils (Cottonvale, Greymare, Lyra, Dalveen, Allan and Bonnie Doon) usually become hard setting if not carefully managed. Contour chisel ploughing or deep ripping using narrow points, helps degraded pastures to recover. Breaking and roughening up a compacted, smooth surface enables rain water to penetrate the soil instead of running offand causing erosion. When tine marks are on the contour, water can pond in themgiving it extra time to infiltrate the soil. However, this practice should be avoided on soils with shallow surfaces and dispersive subsoils e.g. some Roger, Leybum, Lyra, Dalveen, Allan, Maxland, Karangi soils as it may introduce excess water into the unstable subsoil and result in tunnel or gully erosion. 90 LandDegradation The introduction of legumes, such as lucerne and medics by sod seeding on suitable soils, and the occasional use of fertilisers will increase or maintain soil fertility. This, in combination with good grazing management, will result in dense pastures of better quality. 8. 6 Weed infestation and regrowth Ann Starasts and John Gray 8.6.1 Weed infestation and weed management When weeds invade pastures, productivity is reduced. Their infestation can be due to seed spread due to wind or animals, the purchase of hay or stock from other areas, or seed spread on vehicles. Whether or not weeds takehold of a paddock is often due to management. Identifying and controlling a weed infestation is importantin reducing its spread in future seasons. The infestation of weeds in the Stanthorpe Rosenthal region is often due to poor competition from native grasses. This is the result of drought conditions, overgrazing, or cultivating out the native pastures. In many cases, the long-term answeris to improve the growth of the native pastures so they canbetter compete with the weeds. This is particularly true of summergrasses on the lighter soils. Once overgrazed or cultivated out, theytake many years of summer spelling to thicken up. Cropping on alluvial soils: Major annual summer weeds in cultivation include liverseed grass, summer grasses, thornapple, noogoora burr, mintweed and wireweed. Winter weeds include turnip weed, wild radish, thistles, wild oats and climbing buckwheat. Perennial weeds posing serious problems in cultivation on heavier soils include nutgrass, johnson grass and bindweed. These weeds are controlled mainly through crop rotations and herbicide application. Ifa summer weed is a serious problem, winter cropping is carried out in thatpaddock andthe weed controlled (through herbicide or cultivation) through the summer. Irrigated pastures: Dock, turnipweed, thistles and horehound are the most common weeds in irrigated pastures. These can usually be controlled through mowing or baling the pasture, or spraying with herbicide when the weeds are at the small seedling stage. Having a thick healthy plant stand, which is well fertilised and not grazed too heavily, is usually the key to suppressing weeds in an irrigated pasture. Lucerne: Weeds which invade lucerne stands include rnintweed, deadnettle, turnipweed and couch grass. Establishing a vigorous, even standof lucerne in the autumn/early winter is the key to competing withwee ds. Spring and summer sown stands are 91 LandDegra dation subjected to competition from summer grasses early in their life. Herbicides are available to control some weeds in lucerne. Heavy infestations in old lucerne stands are usually cultivated out. Drylandpastur es: Sand burr is a serious problem on sandstone soils. Any cultivation of these soils will almost undoubtedly encourage significant regrowth of sandburr. Band seeding should be practiced on these soils. Sowing previously cultivated soils to a vigorous summer grass, such as premier digit grass or rhodes grass, and fertilising with a small amount of nitrogen fertiliser (15 units of N/ha) will provide competition to the sand burr. Glyphosate will control sand burr prior to the setting of seed heads. Managing individual weeds: Blue heliotrope is probably by far the most widespread weed of both improved and native pastures. It usually appears after periods of heavy grazing or drought. This means that whenever the native or sown pastures are not competitive (as happens in the above situations) blue heliotrope will take hold. It has been suppressed by spraying with glyphosate or by cultivation. Lightening the grazing pressure, especially after rain, will assist native pastures to compete. Johnson grass is a perennial grass which usually takes hold in summer cropping land. It is usually controlled by spraying with glyphosate during a summer fallow. Nutgrass is also a perennial grass which is probably the major weed problem in cultivation areas on black soil (e.g. Pratten). It can be controlled by strategic cultivations through summer and spraying with glyphosate: the aim being to induce tubers to re-shoot andeventually weaken. Lippia (Phyla canescens) or Condamine couch is a major problem in native pastures. It has encroached on creek flats and neighbouring paddocks forming a mass or carpet which completely destroys all native grasses. For smaller areas, it can be sprayed with Lantana DP 600 at 5 L/ha. This rate will control the weed for a number of years, however, it will invariably return. Regular spraying (1 to 2 years) with LantanaDP 600 or 2,4-D amine will suppress the plant enough to allow some pasture growth. African boxthorn is a spiny shrub growing on the better soils around Warwick. It is spread by birds, and ifnot controlled can seriously infest areas. Many woody weed herbicides will control boxthom if applied in the recommended method for this weed. Blackberry is a widespread woody weed which is a serious problem on the Granite Belt. It can be controlled with a range of herbicides if applied in the recommended manner. Bracken fern is also a weed of native pastures in the Stanthorpe area. It can be adequately controlled with herbicides. Rushes (Juncus spp.) invade pastures especially in low lying areas,although it has encroached wider areas. It has been suppressed by slashing, or by encouraging native pasture competition through fertilising and liming. Glyphosate will control 92 Land Degradation the weed, however, it will also kill native grasses. Rope wick applicators, which wipe undiluted chemical onto the plant, have been used successfully. This method kills the weeds and does not touch the native pastures if they are first grazed to below the height of the weed. Tree pear and pricklypear appearfrom time to time. Their growth canbe discouraged by spreading deteriorating parts ofth ese plants(obviously infected with parasites) around the base of healthy plants. Stem injection with glyphosate in tree pear will provide adequate control. Prickly pearcan be sprayed with a number of chemicals. Australianbl ackthorn is a woody weed encroaching timbered pasture areas around the Greymare area. A native beetle exerts some control, but this varies from year to year. Again, there are a small number of herbicides which will control this weed if applied in the recommended manner. Wild rosemary is a woody weed which grows to about one metre high. It infests grazing lands, particularly the harder soils and especiallyfo llowing timber thinning. It is extremely difficult to control. It can be temporarily suppressed with heavy grazmg pressure. Wiregrass infests paddocks which have been overgrazed. It can be suppressed by slashing or burning. Practices which encourage the growth of native grasses, such as spelling and fertilising, will assist in competing with, and suppressing wiregrass. Slender bamboo grass is a significant problem on smaller blocks west of Warwick. It is suppressed by slashing and fertilising. Spelling and encouraging native grasses will discourage its growth. Coolatai grass has occurred in the west and south of thedistrict and is a cause of serious concernfor graziers, as it is not eaten by stock. Mrican lovegrass has infested a number of paddocks in the Stanthorpe Shire and has the potential to be a devastating weed if not checked. This grass is not palatable to stock and istherefore encouraged by heavy and constantgra zing. Native pastures must be maintained through spelling to allow vigorous competition. Inpa stures which have been sown to winter species, there is little competition during the summer, and the lovegrass can gain a significant hold. Heavy grazing (around 20 sheep/ha) has been used to reduce the grass. Glyphosate will control the main species if sprayed in February/March. It should be spot sprayed so as not to kill native pastures. Spelling native pastures during late summer, sod seeding them with summer grasses and fertilising with small amounts of nitrogen, may assist in suppressing the lovegrass. For furtherinformation on weed control, consult the DPI Crop Management Notes, DPI Notes and Department of Lands Pestfacts. 93 LandDeg radation 8. 6.2 Regrowth Regrowth of woody species occurs on grazing lands on which the original timber has been pulled or chemically treated. It is an important economical factor in both its effect on pastures and the cost of controlling it. All the land types in the area are prone to regrowth problems with the exception of the Condarnine Riverflood plains (Mixed basalt alluvial plains landty pe). Regrowth can be of two types: either from seedlings or from old stumps and roots. Some of the species causing a regrowth problem include yellow box, tumbledown gum, cypress pine, bull oak, wild rosemary and wattles. Regrowth species can vary according to land types. For example, wattles and bull oak are more likely to be a problem on sandstone soils, while yellow box, wild rosemary and tumbledown gum can regrow on traprock soils. Areas that have been severely grazed for several years may have a dominance of undesirable plants such as cotton bush, wiregrass or reedy grass with patches of bare soil. Management that allows grass to be continually depleted encourages regrowth problems due to lack of competition. 8.6.3 Managing regrowth Landholders have devised a number of ways to control regrowth according to the scale of their operation and personal preference. Planning: An important step in managing regrowth is to have a plan of attack for controlling the regrowth resulting from the pulling or chemical treatment, before the initial treatment. This plan must take into account the total amount of money available for the initial treatment, and the resultant regrowth control. It is pointless using up all the available money for the initial treatment without having money available for regrowth control. Similarly, the area to be treated needs to take into account the landholder's management needs for regrowth control such as time required and the area that can be dealt with efficiently. Requirements for shadelines and clumps should be planned before the initial treatment. If regrowth is left to form shadelines and clumps, it often consists of almost a monoculture of a certain species. The diversity is lost as slow growing and edible species such as cattle bush, soap ash, wilga and others do not regrow. The shadelines and clumps must be of a sustainable size to withstand the heavy grazing, fire or chemicals used when treating regrowth. The landholder needs to be sure that the increase in productivity expected from the treatment gives an adequate return on capital. 94 Land Degradation Tr eatments: • Some landholders pull the desired area and then immediately graze it very heavily with sheep that eat the leaves off suckers and seedlings. Different mobs of sheep may need to be used if the first mob weakens. The practice is based on the theory that the supply of nutrients of the regrowth roots is depleted if leaves are continually removed, finally resulting in the death of the plant. The area being treated needs to be small enough to allow very heavy grazing, and landholders need to be hard on their sheep. It is important to note that this method leaves the soil surface completely bare and open to erosion. This can be particularly destructive if the area receives high intensity rainfall at this stage. The high stock numbers used places a lot of pressure on surface soil structure and can lead to surface sealing and associated problems of reduced water infiltration and grass germination. • Another method is to pull the desired area and then destock it until it is well grassed up. The area is then subjected to a hot fire on a hot day, after fire breaks have been burnt in or raked in from the edges. Sometimes the fire breaks are burntat night. The area is then subject to very heavy grazing to kill the suckers and seedlings. If landholders are serious about preserving shadelines and clumps, fire breaks are made around these areas before they bum. Some country may have thick wattle regrowth after fire. • Another method may involve pulling the area and then stickraking into windrows. Some landholders stickrake the windrows onto the contour and do not bum them but regard them as shelter for stock and grasses, and allow regrowth in the contoured windrows. Any operations to improve pasture are then done on the contour, between the windrows. Some landholders slash regrowth between the windrows as an alternative to the other methods described. • The occasional landholder uses goats to eat regrowth, but this tends to make some neighbours nervous due to the difficulty of keeping goats fenced in which may result in feral goat problems and wool contamination. • Another method is to use chemicals by individual application, aerial application, or by mechanical spreading. Individual application allows very selective treatment of timber. Aerial application takes careful planningto leave shadelines and is not always successful if a dominant species is not controlled after a lot of expense. Some lateral movement of chemical may occur so shadelines should be very wide to allow for this. To stickrake or not to stickrake ... ? Some landholders stickrake areas on which they have no intention of ever using implements. Stickraking is expensive and therefore can be a waste of finances if the practice is only carried out because of tradition. 95 LandDegr adation On soils that tend to surface seal any scattering of sticks and logs tends to slow runoff water and allow better infiltration. Grasses also grow better close to logs as they are protected somewhat from grazing and have a better microenvironment. Windrows do a similar job, particularly if they are on the contour. 8. 7 Wetness Wetness can occur on the granitecountry, on deep siliceous sands (Banca and Pozieres soils), during or following periods of prolonged rainfall. This is caused by a perched watertable due to rock or clay bars in the subsoil, resulting in the water rising within the plant root zone. Sometimes the water may actually reach the soil surface. These areas often become too wet to be useful with reedy grasses and sedges dominating. Inor chards where the nuisance value of these wet areas has warranted it, the clay barshave been cut in strategic places anddrai ns installed. In cases where the watertable does not rise too much, but comes withinreach of plant roots, the free water is actually beneficial. Impermeable hardpans occurring naturally in Banca and Pozieres soil profiles are also responsible for impeded drainage and wetness. Prolonged rainfall causes waterlogging in the texture contrast soils with poorly structured subsoils of the granite, sandstone and traprock country. Susceptible soils areCottonvale , Greymare, Lyra, Bonnie Doon, Maxland, Karangi andsome Dalveen andAllan soils with less well structured subsoils. Susceptibility to waterlogging depends on the permeability of the subsoil. Flat areas aremore susceptible to wetness than slopes, as surface drainage and lateral movement of free water in the surface layer is restricted. Areas of silt deposition also become wet and boggy after rain. Although wetness and waterlogging occur naturally in the area, the clearing of timber and ploughing of soils have resulted in an increase in their incidence and severity. Waterlogging causes bleaching of subsurface soils andloss of fertility through the leaching of nutrients. 8. 7.1 Managing soil wetness Areas which are prone to wetness are best left under native grass and timber, and should not be grazed at all when wet. Retaining timber on rugged unproductive areas, hill tops, rocky outcrops and ridges, and in belts on the contour, reduces seepage and therisk of rising watertables because of the ability of trees to use water from a considerable depth within the soil profile. A dense, permanent winter and summer pasture mix will also aid in drying out soil profiles through a higher year round water use. Runoffwa ter may be intercepted and diverted away from areas prone to wetness. On the horticultural cropping lands, subsurface drainage works may be economically installed in critical areas. 96 Land Degradation 8. 8 Salinity Salinity in soil refers to the concentration of soluble salts in thesoil solution. Salts are a natural component of all landscapes. Salinity in the environment results from the weathering of rocks and other sediments, or canbe blown inland from coastal areas. Water dissolves any salts present in the soil, therefore the flow of water in the landscape determines the movement and the final distribution of the salts. Plants and animals tolerate different levels of salinity in the water they use. Salts can build up in particular areas of the landscape and may cause problems for land managers, such as restricting the range of land uses and level of production. An understanding of the landscapes within the catchment will therefore assist to identify sources of salinity. Some of the factors which contribute to salinity are: • rising watertables which may result from tree clearing, housing developments or irrigation; • irrigating with saline water; • addition of some fertilizers; • climatic conditions; • geological configurations such as folding, faulting and dykes, and topographical constrictions such as two adj acent hills which restrict water flow; • past and present landuses; • soil types; • placement of roads on valleyfl oors; and • confluence of streams. Photo 8.2 Bare patches due to salinityon flatgranite plains 97 LandDegr adation Some recognisable features of an area affected by salinity include: • dying trees and grasses; • patches of bare ground; • areas which remain wetter than surrounding areas; • the presence of salt tolerantvegetati on; • fluffy or powdery soil surface; • salt crystals on the surface; and • water that has a salty taste. The area affected by salinity in the Stanthorpe-Rosenthal region is not great, with a few saline patches occurring in the region. Scalded areas devoid of vegetation occurring on Rodger andLyra soils are highly saline, sodic and alkaline. The area affected by salinity may increase in the future due to the extensive timber clearing practices that have been carried out in the past. 8.8.1 Ma naging salinity As seepage and rising watertables can lead to salinity, measures used to control wetness as described in the previous section are relevant for the control of salinity. The establishment and/or maintenance ofvegetative cover on affected areas reduces the evaporative concentration of salts on the soil surface and erosion. Selective revegetation, drainage and ground water pumping are also management options for affected areas. The quality of groundwater in areas affected by salinity should be monitored before using for irrigation. 8.9 Streambank erosion Streambank erosion is a problem along the Condarnine and Severnrivers , Pike Creek and other watercourses in the area. Streambanks are eroded by clearing, grazing or cultivation of banks and adj acent areas. Vehicular trafficup and down banks, and the removal of soil and gravel are also major contributing factors. Obstructions to stream flow,such as fallen trees and sediment deposits, or trees growing on the inside of a bend, may deflect stream flow to vulnerable locations, such as the outside curve of a bend, resulting in streambank erosion. 8.9.1 Managing streambank erosion Livestock should be excluded from streams generally, but especially from unstable or potentially unstable areas, or areas under repair. When access is required, careful location and stabilisation of tracks is necessary. If grazing must be used to control weeds, a short period using high stocking rates of lighter type stock (e.g. young cattle) is preferable, and has lower impact than low stock numbers over an extended period. Natural vegetation should be retained on streambanks as well as an area 98 Land Degradation adj acent to the streambank. When damage does occur, repair and maintenance work should be undertakenimmediat ely. Careful planning of any restoration work in the river/stream system is essential. Seek advice from the local DNR Resource Management staffor River Improvement Trust before starting any work. Further Reading Bierenbroodspot, J. and Jamieson, G.I. 1983, Farm Layouts fo r Intensive Cropping, Information Series QI83012, Queensland Departmentof Primary Industries, Brisbane. Lucy, M. 1995, Lipp ia (Phyla canescens): a review of its economic and environmental impact on flood plain ecosystems in the Murray-Darling Basin, Pittsworth Landcare Group, Pittsworth, Queensland. Nufarm 1996, Lippia - a major problem of river floodplains, Spectrum Note, QLD AG-2 February. 99 100 9. LAND PLANNING AND MANAGEMENT - STRATEGIES FOR SUSTAINABILITY 9.1 Introduction Barry Stone and Emma Bryant A basic planning principle is that land (i.e. soils, vegetation, landform and hydrology) should be used within its capability if sustainable land use is to be achieved. This principle applies to all levels of planning whether it be at the property scale or the broader catchment or local government area scale. The first step in developing a plan for land use and land management should involve a careful assessment of the land's natural features, in terms of its capability and suitability for a range of uses, and the inputs and management required for sustainable use. For example, in the case of farm planning, an area of land could be suitable for grain cropping with the additional inputs of fertilisers and run-offcontr ols. For local governmentplanning an area of land may not be suitable for residential development unless reticulated sewerage is provided. Land planning is an on-going process. Once a plan has been implemented, monitoring of its outcomes should occur to determine whether modifications to the plan are necessary. The information contained in this Manual will provide a basis for developing land use and management plans at any scale. The Land Type Map and accompanying report can be used to identify suitable land uses and management at a broad scale. Section 4.3 on land suitability, for instance, describes broadly the suitability and limitations for use of the 21 land types in the area. The specific land type sheets can provide more detailed information useful at the property level if more detailed surveys are carried out to identify different soils. The following sections in this chapter outline some of the processes used in different levels of planning to achieve sustainable land use, namely farm planning and regional planning. In particular, regional planning focuses on local government land use planning and catchment planning. 10 1 LandPlanning and Management - Strategies for Sustainability 9.2 Farm and regional planning Barry Stone and Emma Bryant 9.2.1 Farm planning A farm plan combines the knowledge, experience and desires of a landholder with the technical knowledge and expertise of the land management planner. The plan will show how the land can be developed and managed for economic returns and at the same time allows for the sustained use of the resources. To ensure sustainable production goals are possible an understanding of the limitations of the land resource and the potential for degradation through misuse is required. There are four broad components of a farm plan: • resource plan (or resource inventory); • a capability plan; • land use plan; and • property management plan. The resource plan Prominent features (such as watercourses, ridges or catchment boundaries and vegetation patterns) are identified from an aerial photo or other resource map, and marked onto an appropriate base plan. Other details are added such as existing land uses, fencing layout and access, water storages, watering points, buildings and yards. Opportunities for enhancing, or further developing the natural resources should be assessed and noted, for example, value of timber for commercial use or for shelter, windbreaks, or wildlife habitat; or quantity and quality of water and the potential to irrigate. A landholder interested in managing the farm efficiently and maintaining its productivity should give due regard to natural environment concerns, such as the maintenance of wildlife habitats and the preservation of remnant vegetation. Th e capability plan After assessing the land components, there is a need to identify the capability of the different landty pes to ensure no part of the property is developed or used beyond its sustainable potential. Mapping should include land slope, landform, vegetation patterns, and soils and their characteristics. This information is then used to classify the land according to the limits of safe land use, the required management techniques and the hazards attached to specific use of the land (Rosser et al. 1974). In time, such land classifications may be altered as economic conditions and/or technology change, allowing for alternative,but safe, use of the land. For farm planning purposes, the land evaluation method described by Rosser et al. (1974) is practical. This system divides agricultural land into eight classes based on 14 limiting factors that can affect the land's sustained production. Details of 102 Land Planningand Management - Strategies for Sustainability the 14 limiting factors can be found in Rosser et al. (1974), but the following broad groups are noted: • Factors limiting choice of crops or crop productivity,i. e. climatic, moisture availability, soil depth, soil physical factors, nutrient fertility, soil salinity or sodicity; • Factors limiting the use of agricultural machinery or accessibility, i.e. topography, soil workability, stoniness, surface micro-relief or wetness; and • Factors controlling land deterioration, i.e. susceptibility to water erosion, wind erosion, or flooding. To determine land capability, the farm planner should first identify those areas where obvious limitations occur. Examples of these may include: • steeply sloping areas which make the use of farm machinery difficult, or which have a high risk of erosion; • rocky or wet areas not suitable for cropping or pasture improvement; and • areas where the soil features (e.g. surface compaction, depth, dispersibility) result in low agricultural potential. After these have been identified and mapped then a detailed assessment can be made of the remaining land using the soils information given in the land type sheets. Once the land capability plan is completed then the land use plan is prepared taking into account the managerial skills and the financial resources available for the preferred enterprise. Th e land use plan For agricultural production purposes the following options for land use may be applied to each parcel of land: • cultivation, grain (summer and winter), fodder cropping, horticultural cropping; • improved pastures, introduced grasses and/or legumes; • native pasture production; and • areas of limited agricultural use. Sections 9.3-9.8 outline strategies for ensuring sustainable land use with agricultural enterprises based on the above options. Different inputs may be required for each management unit, depending on the adopted enterprise. For example, the land capability study may define a parcel of land suitable for growing lucerne,or for a horticultural cash crop, but the inputs will differ depending on which crop is grown. Adding fertilisers and irrigation water may be sufficient to overcome the specific limitations for lucerne growing; but for a cultivated horticultural crop it may also be necessary to implement an intensive runoffcontrol system. The land use plan therefore, should identify the particular requirements for each parcel of land according to the expected enterprise. A land use plan for a particular property may also need to coordinate its runoff control requirements with those works required on neighbouring properties (see Chapter 8). Often, the location and the time of installing these works on one 103 Land Planning and Management - Strategies for Sustainability property, can affect related works on upstream or downstream properties. Cross drainage structures on public utilities such as roads, railways or irrigation channels, should also be coordinated as part of an overall catchment plan. Th e property management plan The property management plan describes the measures and action required to change a property from the current to the desired land use, considering also the available financial constraints and resources. This plan should be flexibleand modified as needs change and financial resources allow, depending on the external economic influences. Special care is required to ensure timely and proper development. For example, excessive clearing early in development of a property may require additional time and costs in later regrowth control. Planning for areas to be cleared should give regard to the need to retain trees for shade, shelter and timber supplies and the possible effects on the risk of salinity outbreaks. Indiscriminate clearing of native vegetation can result in loss of floraand fauna, and this can lead to a build-up of pest populations affecting crops and pastures. Productivity can be reduced through lack of wind protection in pastures and crops (especially tree crops), and through lack of shade and shelter for grazing animals. Key runoffcontrol works should be located before clearing sloping land, so that runoffdisposa l areas are disturbed as little as possible. For some landforms, the top contour or diversion bank will define the upper clearing limit. Drainage lines may require stabilising with grass before runoffcan be directed into them; and if defined channels do not exist, artificial waterways may have to be constructed (see Chapter 8). 9.2.2 Regional planning A regional plan differs from a farm plan in that it is used for planning land use and management over more than one property, and it often includes non agricultural uses. Local governments have the major responsibility for regional planning under their strategic planning process. Local government plans focus on allocating land between differentland uses and minimising conflictbetween uses. Increasingly, they are considering the quality of the land resource, and protection of environmental values in decision making affecting land uses. Integrated Catchment Management (ICM) committees also play a role in regional planning. Their main focus is on developing management strategies that help achieve sustainable use of the natural resources in a catchment. In particular, ensuring that land use does not adversely impact on water quality. ICM can provide advice to local governments when they are developing their land use plans, to ensure land uses are appropriately located and managed. To achieve sustainable land use, local government and iCM should work closely together. The Manual covers the Shire of Stanthorpe and the westernpart of Warwick Shire. Both local governments have been preparing plans with a strong natural 104 Land Planning and Management - Strategies for Sustainability resource focus. There are two ICM committees operating in the Manual area: the Border Rivers Catchment Coordinating Committee in the south and west and the Condamine Catchment Coordinating Committee in the north. Farm planning should also occur within a regional planning process, preferably within watershed catchments. Individualfarm plans should integrate with those of neighbouring farms so that an overall coordinated approach is achieved. This is important for the effective application of a range of measures across the catchment, for instance, coordinated runoff control schemes, wildlife corridors and watershed protection. As a number of communities are usually affected by regional planning, it places a strong emphasis on community involvement and education. The community should always be involved in developing objectives for their area. Assessing land characteristics As with farm plans, one of the first steps in developing a regional plan is to assess the natural resources of the area. However, because the plan covers a much larger area, the requirements of other land uses, such as urban, industrial, transport systems, recreation and water storage, also have to be considered. Determining the land's suitability for this greater range of uses necessitates collecting a much larger range of resource information. This includes data on climate, topography, geology and soils, vegetation, water resources, domestic and wild animals, fire, community and physical infrastructure, population trends, employment opportunities, economic development and community needs and expectations. Once the resource information has been collected, planners can determine the land's suitability for a range of uses, both agricultural and non-agricultural, with the aid of a computer-based geographic information system (GIS). Other assessments that are also often made are potentials for land degradation such as erosion and salinity. Some areas of the region may require more detailed assessment than other areas because of greater demand by competing land uses, for example rural areas near urban growth centres. Good quality agricultural land A local government, whendeveloping a strategic plan, has to balance the needs of rural land users with those of non-rural land users such as urban residents. The localgove rnment has to consider the potential for conflict, and measures to reduce the risk of conflict, between land users involved in agricultural production and urban dwellers in close proximity. Good planning, particularly at the Shire level, is necessary for protecting natural resources, the lifestyles of current generations and the well-being of future generations. Initiatives have been developed, at both local and State level, to facilitate good planning. One of these is the introduction of the State Planning Policy on agricultural land. 105 LandPl anning and Management - Strategies for Sustainability Good quality agricultural land, 'land which is capable of sustainable use for agriculture, with a reasonable level of inputs, and without causing degradation of land or other natural resources', is a scarce resource in Australia and Queensland. Approximately 6% of Australia and only 4% of Queensland is regarded as productive cropping land. Yet agricultural products are a significant contributor to our export income. It is for these reasons and others, such as retaining our rural heritage and providing a base for secondary industries, that good quality agricultural land should be protected from non-rural uses wherever possible. State Planning Policy 1192: Development and the Conservation of Agricultural Land was formulated to allow good quality agricultural land to be identified and protected, (DHLGP 1992). The policy requires both Local and State Governments to be aware of the location of good quality agricultural land and to protect it through planning instruments such as strategic plans. To assist government with the policy, a set of guidelines, Th e Identification of Good Quality Agricultural Land (DPI & DHLGP 1993), has been prepared. These guidelines identify which land types in a local governmentarea are considered good quality agricultural land and assigns each of these land types an Agricultural Land Class. Definitions of the Agricultural Land Classes are given below: Class A: Crop land Land suitable for current and potential crops. All crop land is considered to be good quality agricultural land. Class B: Limited crop land Land marginal for current and potential crops; and suitable for pastures. Land marginal for particular crops of local significance is considered to be good quality agricultural land. Class Cl: Pasture land Land suitable only for improved or native pastures. In areas where pastoral industries are predominant, improved pasture land may be considered as good quality agricultural land. Class C2: Pasture land Land suitable only for native pastures. In areas where pastoral industries are predominant, native pasture land may be considered as good quality agricultural land. Class D: Non-agricultural land Land not suitable for agricultural uses Table 9.1 identifies the suitability of each of the 21 land types described in this Manual for different agricultural uses and their dominant agricultural land class. This information may be used for regional planning in conjunction with the Land Type Map (see Map 6, back pocket). 106 Land Planning and Management - Strategies for Sustainability An example of how agricultural land is being protected at the local level is found in the development of the Stanthorpe Shire Strategic plan (Stanthorpe Shire Council 1996). This plan includes a map indicating the location of good quality agricultural land and a set of land use controls necessary to protect the agricultural activities in each area. For example, minimum lot sizes reflect the dominant agricultural uses in each area; the traprock has very large minimum lot sizes to protect the grazing industry and the Granite Belt has smaller lot sizes to reflect its more intensive horticultural uses. Subdivision for residential uses in the rural areas of Stanthorpe Shire is strictly controlled, and buffering policies have been introduced to prevent conflict between existing residential dwellers and rural operators. Areas more suitable for non-agricultural uses, such as rural residential development, have also been identified. These policies are essential in protecting the Shire's uniqueness and long-term future prosperity. Non-agricultural uses The information in this Manual, although predominantly presented for agricultural land users, can also provide a guide to the suitability of land for non-agricultural uses. For example, information such as land slope, flooding, soil depth and drainage characteristics for each land type can provide a general suitability assessment for effluent disposal using septic tanks. Details on the types of land information used for land suitability assessments for urban development can be found in Atkinson (1991). This includes: engineering suitability (or limitations); erosion hazard during the development phase; and suitability of soil material for revegetation. 107 LandPla nning and Management - Strategies for Sustainability Table 9.1 Land use suitabilityand agricultural land classes fo r land typ es in the Stanthorpe Rosenthal region Land Type Dominant Land use suitability Agricultural Soil Land Class Grain Hort Improved Native crops crops pasture pasture Mixed basalt alluvial plains Pratten s NS s s A Granite/traprock alluvial plains Rodger LS NS s s B Traprock/sandstone alluvial plains Leyburn LS NS s s B Rolling granite mountains Banco NS NS NS LS C2/D Granite hills Banco NS LS LS s C2 Undulating low granite hills Banco LS LS LS s B Granite rises-uniform sands Pozieres LS s s s A Elevated granite plains Cottonvale NS s s s A Undulating granite plains Cottonvale NS s s s A Granite rises-texture contrast soils Greymare LS LS s s B Flat granite plains Lyra NS NS LS s C2 Sandstone ridges Hanmer NS NS NS LS C2 Undulating low sandstone hills Dalveen NS NS LS s Cl Mardon LS LS s s B Undulating sandstone rises Allan LS LS s s B Gently undulating sandy rises Bonnie NS NS s s Cl Doon Drome NS NS s s Cl Gently undulating sandstone plains Maxi and NS NS s s Cl Traprock mountains Gammie NS NS NS LS C2 Karangi Ns NS NS LS C2 Undulating to rolling traprock hills Gammie NS NS NS s C2 Karangi NS NS NS s C2 Low traprock hills Gammie NS NS NS s C2 Karangi NS NS LS s Cl Traprock plains Karangi NS NS LS s Cl Elevated low traprock hills Glentanna NS NS s s Cl 5 = Suitable NS = Not Suitable LS = Limited Suitability 108 Land Planning and Management - Strategies for Sustainability 9.3 Nature conservation Bruce Lawrie Nature conservation on rural land aims at achieving a balanced system which can sustain long-term productivity. Retaining shade and shelter for livestock, and windbreaks for crops are practical demonstrations of conservation initiatives. Less obvious benefits of integrated planning include watershed protection, and retention of biological gene pools of native plants and animals with possibly unrecognised economic benefit. From a different viewpoint, farm hosting and 'ecotourism' are developing trends across rural Australia. The role of native predators in regulating or controlling both native and introduced pest fauna and insect populations is substantial, although difficult to quantify. Insects can play a major role in controlling insects affecting the health of trees (Loyn et al. 1983). Mammals such as sugar gliders also consume substantial amounts of insects (Loyn 1987). Adaptable 'farm land' species, such as magpies and peewees, are of obvious economic benefit to farmers on developed lands. However, they cannot substitute for the range of insectivores naturally adapted to timbered habitat and contributing to tree health. To effectively achieve conservation of the full range of wildlife in the Stanthorpe Rosenthal region requires retention of a mosaic of habitat across all land types. Strategic use of certain wildlife management principles can maximise conservation efforts. Seemingly modest areas of farm-based habitat linked to roadside vegetation, stock routes, Crown reserves, State Forests and National Parks become important habitat refuges across the catchment. Riparian vegetation bordering watercourses provides vital habitat and movement corridors for wildlife, particularly arboreal mammals such as koalas and gliders, and a range of resident, nomadic and migratory bird species. Larger clumps are generally more effective for wildlife than small fragmented patches, which are separately exposed to edge effects such as wind, fire, stock pressure and insect attack. Accordingly, the smaller and narrower the remnant shape, the more susceptible it can become to environmental impacts, such as runoff and consequent erosion. Research on the New England Tableland, in north-easternNew South Wales, indicates that a 20 ha woodland clump can have a rich bird community, provided it is not too isolated from other native vegetation. 109 Land Planning and Management - Strategies for Sustainability Smaller patches (5 to 10 ha) can still have a rich bird community, provided the aggressive territorial noisy miner is in low numbers. It appears that once a remnant area of woodland gets below 5 ha, the native ecosystem is likely to collapse (Barrett et al. 1993). Certain fauna species require large home ranges which cannot be realistically accommodated in intensively developed agricultural areas. A mosaic of retained habitat across the landscape is therefore essential to avoid limiting genetic exchange in isolated fauna populations. Scattered trees across the paddock present an attractive park-like effect and can be of practical value in achieving more even grazing. However, this retention pattern provides only incidental benefit to the majority of wildlife species. To maximise wildlife productivity, aim to include a range of representative land types within selected remnants. Attributes to incorporate within areas of retained land types include, maintaining the full range of understorey canopy layers in timbered habitat, good ground cover, hollow logs, standing trees and wetland areas. Control of regrowth from previous land development is a major management task in the Stanthorpe-Rosenthal region. It is important to recognise that clearing can reduce diversity through changes in the make-up and structure of regenerating species such as yellow box. However, the vigorous growth provides for opportunities to reform links with retained remnants or increase the area of existing patches. Local timber management guidelines developed through the inter-Departmental regional consultation process provide a reference for land development. Specific information on wildlife management for both conservation and control of problem native species is available from Department of Environment extension officers. Landholders on rural residential blocks may feel limited in what can be achieved on small blocks which are partially disturbed by previous development. However, in many cases the opportunity exists to develop the block primarily for wildlife values. The key is to consider the block as part of thelocal catchment. Use tree guards to protect individual trees from horses. Link in with neighbours to jointly fence remnant areas from stock to preserve vegetation understorey and ground cover, and rehabilitate overgrazed or eroded areas. 110 Land Planning and Management - Strategies for Sustainability 9.4 On-farm tree management Peter Voller 9.4.1 Introduction Tree management on farms in the Stanthorpe-Rosenthal region can be in several forms: • managing native forests for wood production; • retaining areas of native forest for land protection purposes; • planting trees for timber production or economic benefit; and • planting trees for land protection. 9.4.2 Managing native fo rests fo r wood production Timber production from native forests on farms in the Stanthorpe-Rosenthal region is limited by a number of factors. The most significant of these are long harvesting cycles (slow forest growth rates) and limited numbers of suitable species. Presently, very small areas of native forests are harvested commercially in the area. In general, trees on the Granite Belt and traprock areas have short log length and are frequently bendy. Forests on the sandstone have less defects, but must contend with significant weed competition. The largest markets for native forests are in round timbers for fencing and firewood. Some limited harvesting of spotted gum and ironbark for saw logs occurs in the Karara!Leyburn area. Harvesting cycles in these areas are estimated at 70 to 100 years. 9.4.3 Retaining areas of native fo rest fo r land protection purposes Balanced retention of native forests has significant environmental and land protection benefits in the Stanthorpe-Rosenthal region. While it is often necessary to clear or thin native forests to provide land for grazing or agriculture, it is also important to retain areas for stock shade, windbreaks, woodlots, wildlife habitat and as part of an erosion control strategy. Specific tree retention plans should be developed as part of a property plan and in consideration of soil type and slopes. On leasehold land, tree clearing permits or a tree management plan will be required before clearing is undertaken. Advice on tree retention strategies can be obtained from the Department of Natural Resources (DNR), Department of Environment (DE) or local Landcare representatives. 111 LandPla nning and Management - Strategies for Sustainability 9.4.4 Planting trees fo r timber production or economic benefit Options for timber production on farms in the area are limited and specialised. The most successful plantation activities to date have been Pinus radiata plantations on the Granite Belt. Properly managed pine plantations can reach harvestable size within 30 to 40 years on the Granite Belt. Proper management would include early weed control, fire protection and timely thinning. Commercial plantations should be thinned to around 300 stems per ha well before final harvest. Other species options such as eucalypts and native cabinet wood species are considered to have limited potential to produce an economic crop in this area, but there has been no recent trial work to confirm this. Exotic plantation species other than Pinus radiata have been trialled by DPI Forestry over many years on the Granite Belt, but few have proved to perform as well. Some private trial plantings of Paulownia trees have been established recently in this area, but these plantings are still too young to provide any clear indication of productivity or economic return. Indications from similar areas suggest that this species requires highly specialised management and that growth rates decline rapidly with age. Other commercial uses for tree plantings could include: • Flower and foliage production. There have been some plantations of native plants including eucalypts and banksias for the floral market. This industry has the potential to be quite lucrative, but it is very specialised and requires high infrastructure costs. It is highly advisable to seek accurate and reliable information on species selection and market suitability before investing in this industry; • Fruit and nut crops. Some new crops are being investigated in the area and the best source of advice on these plants is from the DPI Applethorpe; • Crop or animal protection. Tree and shrub plantings for windbreaks or shelterbelts have been recorded as contributing significantly to improved profitability of plant and animal production. In tree fruit crops, windbreaks are valuable in reducing the level of wind rub damage. Properly designed shelterbelts can also help in cold air drainage, thus reducing frost damage. Wind shelter is also valuable in animal production, newly shorn sheep, lambing ewes and sick animals have higher survival potentials if climatic extremes are moderated. 112 Land Planning and Management - Strategies for Sustainability 9.4.5 Planting trees fo r land protection Tree planting for land protection is highly specialised and site specific. Whilst it may be economically feasible to retain large numbers of trees for land protection purposes, the costs involved in large scale tree plantings are high enough to warrant very careful planning. Tree planting costs in the Stanthorpe-Rosenthal region are in the vicinity of $3.00 to $10.00 per tree (including site preparation, trees, guards, mulch and labour). This makes the planting of hundreds or even thousands of trees prohibitive. Planted trees can be used in a number of ways to protect land. These include: • reduction of wind erosion; • streambank and gully stabilisation; and • deep nutrient cycling. For each of these uses, the role of the trees must be set out as part of an overall strategy for land protection. Other activities such as grass establishment, stubble management, and property planning may be required. Advice on tree planting projects can be provided by DNRReso urce Management, DE, and Landcare members. Local nurseries may also be able to help. 9.5 Horticulture Steve Tancred 9.5.1 Soil erosion control Soil erosion control has traditionally been difficult in dryland orchards and vineyards. As the inter-row areas are clean cultivated for weed control and moisture conservation, the soil is prone to erosion during summer storms. However, with the advent of irrigation, in particular trickle irrigation, weeds are controlled in most orchards and many vineyards with herbicides placed in a strip along the row, with mowing, or only occasional cultivation of the area between rows. The soil in this inter-row area is then held together by sown grasses, legumes or weeds. An added advantage of this system is improved trafficability after rain. Investigations show that a 'living mulch' system under the tree or vine, uses growing weeds as ground cover, while controlling the impact of these weeds through the use of knockdown herbicides. An additional impediment to erosion control is the general lack of suitability of many properties for contour bank systems. Rocky outcrops, areas of shallow or 113 Land Planning and Management - Strategies for Sustainability poorly drained soil, and small individual property sizes interfere with contour orientations. In addition, there are farming efficiencies in planting orchard and vineyard rows in straight lines rather than on contour lines. Because of occasional periods of excessive rainfall and the risk of tree and vine roots rotting in waterlogged soils, many producers opt to plant up and down the slope to enhance runoff. Horticultural crops require many machinery operations, and badly placed orchard roads can cause water concentration and erosion. To balance these horticultural considerations with the need for soil conservation, producers should: • use head drains and diversion banks from upland areas to limit water flowing onto cultivated land; • locate main farm roads away from unstable areas or drainage lines; • construct roadways and access tracks in a manner which minimises potential erosion resulting from concentrated water flow; • build farm catchment dams which reduce the erosive effects of long overland fl ow; • site dam by-washes so that this overflow is managed with minimal erosion potential; • grow green manure cover crops in clean cultivated areas during winter or before replanting; • arrange orchard or vineyard replant areas to maximise the benefits of cross slope planting direction whilst still retaining flexibility for cultural activities; and • improve soil structure through regular soil amelioration using wood waste materials and animal manures. 9.5.2 Drainage Good drainage is very important for all horticultural crops and the sandy, granite topsoils are naturally well drained. However, because many of these soils are shallow or have underlying clay or impervious layers, waterlogging can occur after heavy or sustained rains. Of the Granite Belt crops, vegetables, stone fruit and grapes are the most prone to waterlogging damage; apples are less prone and pears have some tolerance. As well as open drains around andthrough cropped areas, many soils require underground gravel or pipe drains. To increase soil depth in the rooting zone and improve localised drainage, many producers mound soil around trees and vines, along the rows. This is particularly effective in trickle irrigated areas because most roots are concentrated under the wetting zone and improving soil depth in this zone will improve growth. 114 Land Planning and Management - Strategies for Sustainability 9.5.3 Soil fe rtility and structure Before planting any crops in Granite Belt soils the fertility, organic matter content and pH have to be improved. The granite soils are naturally acidic and low in most nutrients and organic matter. Cropping further acidifies and depletes nutrients in these soils. Pre-planting additions of lime or dolomite, manure or sawdust and some fertilisers are standard practices. Periodic fallowing of vegetable land and the planting of green manure cover crops improves structure and fertility. Increased organic matter can also reduce soil nematode populations, and improve growth in areas being replanted to trees and vines. 9.5.4 Salinity Salinity has traditionally not been a problem in many areas because most irrigation water is from catchment surface runoff and any salinity is easily leached out of the sandy surface soils. However, with ongoing dry weather, more supplementary underground water supplies are being developed and trickle irrigation is concentrating water in the rooting zone. As a result, more areas of salinity are being found on the Granite Belt. It is envisaged that periodic heavy rains following a return to 'normal' seasonal rainfall patterns will leach any residual salt to below the rooting zone. 9.5.5 Soil compaction Frequent local traffic on fruit and vegetable farms is unavoidable because of the many cultural operations that need to be performed during the life of a crop. Soil compaction can be reversed by annual deep ripping of vegetable land, but can only be addressed between plantings in orchards and vineyards. Increasing soil organic matter content and the growing of inter-row swards can reduce compaction and improve water infiltration in these areas. This results in the dual benefit of reducing soil erosion potential and increasing soil moisture for adj acent crops. 9.6 Pastures Ann Starasts 9. 6.1 Native pastures Stocking Rates Maintaining a conservative stocking rate year-round may assist in maintaining soil cover and soil fertility levels over a long period. This should aid rainfall infiltration and help to ensure the long-term productivity of pastures (see Figures 1 and 2). Good cover will also assist the pasture to compete with weeds. 115 LandPla nning and Management - Strategiesfor Sustainability 30 25 ,-._ "" 20 � 5'-' 15 = .....0 <:IJ 0 "" 10 � 5 0 10 20 30 40 50 >60 Ground cover % Figure 9.1 Effe ct of pasture ground cover on annual soil loss Source: Agricultural ProductionSyst ems Research Unit, DPI Toowoomba 250 200 ,-._ "" i 150 '-'e it: 0 = 100 = � 50 0 0 10 20 30 40 50 60 70 80 90 100 Ground cover % Figure 9.2 Effe ct of pasture ground cover on annual runoff Source: Agricultural Production Systems Research Unit, DPI Toowoomba 116 LandPlann ing and Management - Strategies for Sustainability Spell pastures Constant grazing of pastures leaves little chance for grasses or legumes to seed and produce more tillers. It is recommended to spell pastures at least once per year during summer, for a period of 2 months, to allow seeding. This will provide standover feed for autumn grazing. If this is not possible annually, then attempt to spell each paddock every 2 years. Pastures with a winter component such as clovers, medics or ryegrass should also be spelled in October to allow them to seed. Monitor and avoid overgrazing Locate supplementary feeding and watering points in least grazed areas to encourage stock to graze them. Graziers should monitor paddocks closely to identify areas that are badly overgrazed (and temporarily fence off if necessary). Monitor and control weeds Monitor paddocks for weeds and control infestations early. Encourage legumes Glycine is a native legume which will grow over much of the grazing area covered by this Manual. It can be encouraged by lighter stocking rates and grazing with cattle rather than sheep. The addition of superphosphate will also assist its growth. Improving feed quality The disadvantage of native pastures is their lack of quality feed during winter and early spring. Standover frosted grass has very little protein or energy and supplementary feeding of stock is necessary. Some options to improve the quality of native pastures include: • Selective timber thinning: Selective timber thinning may encourage regeneration and thickening of native grass stands. This should only occur on areas where soils are deepest and more friable. There may be limited responses in hard setting soils. • Topdressing pastures: Topdressing native pastures with superphosphate has occurred on a number of properties throughout the area, usually in good seasons. The benefits have been varied but in some cases quite good, usually through better stock performance. This is particularly the case on the sandier soils of the Granite Belt. Superphosphate rates applied have been in the order of 250 kg/ha. • Oversowing pasture seed: Oversowing with legume or grass seed may be beneficial on the sandier granite soils in a high rainfall area. Germination is usually poor on traprock and other hard setting soils, and in drier environments. Trials have indicated that May is the preferred month for this practice. Seed coating, particularly grass seeds and inoculated legume seeds, may improve 117 Land Planning and Management - Strategies for Sustainability growth of the plants. Total seeding rates would be around 2-5 kglha (white clover, subclover or medics and ryegrass). • Band seeding pastures: Band seeding (or sod seeding) legumes into native pasture involves sowing legumes behind a chisel plough with narrow points and widely spaced tines. This produces minimal disturbance to native pastures. It has occurred on a number of properties and demonstration sites across the area with reasonable success. The practice involves waiting until the onset of a heavy frost to halt native grass growth. The seed is then placed on the surface, or preferably just under the surface. It is often difficult to sow small seeds at a depth of 1 to 2 em and so it is usually recommended to drop the seed behind the tine on the surface, rather than try to bury the seed at such a shallow depth. Seed coating may assist establishment. April-May are the recommended months during which to sow winter legumes and grasses. As superphosphate is applied in a band around the seed, overall rates of application per hectare are much reduced. If including grasses in higher rainfall granite areas, topdressing with nitrogen fertiliser (15 units/ha) once established, will assist growth. Maintenance fertiliser dressings on all soils could include superphosphate (100 kglha). Stocking rates on native pastures rangefrom about 1 DSE to 0.8 ha. With pasture improvement, stocking rates in particular paddocks could double on the more friable granite soils and where rainfall is >850 mm. Don't cultivate native pastures Cultivating native pastures is not recommended on many soils in the region. Because of the poor fertility of many soils, once cultivation is abandoned, native grasses will not regenerate adequately, and a bare paddock will result. Even after 7 to 8 years, paddocks may still not be adequately grassed up. Cultivating native pastures in order to sow forage crop or improved pastures should only be considered where native pastures have already been depleted due to previous cultivation. It is important to get a surface cover on these soils, by maintaining crop stubble throughout the summer, or by sowing pasture grasses. Summer grasses and winter legumes can be sown together in late February. 118 Land Planning and Management - Strategies for Sustainability Photo 9.1 Sod seeding coated grass seed into pastures, Vermont, Warwick Photo 9.2 Premier digit grass sod seeded into grassed paddock, Elbow Valley 119 Land Planning and Management - Strategiesfor Sustainability 9. 6.2 Improved pastures Significant areas of improved pastures exist in the area, particularly on the eastern granite soils where rainfall is higher. To help ensure the long-term sustainability of these pastures: • lighten stocking rates in October and January to allow winter and summer pasture species to seed; • maintain a good legume proportion in pasture - spell pastures to let legumes seed and germinate, band seed or topdress to increase the proportion of legume (or grass if necessary); and • fertilise summer grasses with a nitrogen fertiliser (DAP or Crop King 700). On many soils in the area it is not advisable to cultivate even a thinning pasture stand, as there are risks in establishing a new stand, and surface cover is important to reduce erosion and increase rainfall infiltration. Sod seeding or chisel ploughing with narrow points to renovate thepasture is the preferred method. Table 9.2 Recommended grasses and legumes fo r pasture improvement GRASSES LEGUMES Lower Rainfall ( <800 mm per annum) Soil pH >5.5 (usually traprock soils) premier digit grass, rhodes grass (Katambora), white clover, subclover, medics, lucerne paspalum (winter active varieties; sown <0.5 kglha) Higher Rainfall (>800 mm per annum) Soil pH <5.5 (granite and sandstone soils) premier digit grass, kikuyu, paspalum white clover, subclover, serradella (sandy soils) Sowing Rate 1-2 kglha Sowing Rate 2-5 kglha 9. 7 Cultivation Ann Starasts 9.7.1 Forage cropp ing Where paddocks are to be sown for oats or other forage crops, they are often left bare through the summer, leaving them prone to erosion. The following strategies will help ensure the long-term sustainability of farming systems relying on forage croppmg. • Leave stubble standing through fallow: Do not graze forage crops (such as oats) to ground level, but leave stubble standing to 15 em to act as a mulch throughout summer. Sow summer forage crops in other paddocks early to enable stock to stop grazing oats and leave some standing stubble. Use herbicide sprays to control weeds in the fallow; 120 Land Planning and Management - Strategiesfor Sustainability • Sow crops into stubble: Sow following crops into the slashed stubble with a stubble handling planter. Where stubble handling equipment is not available, do not cultivate through the fallow, cultivate immediately prior to sowing. On the more sandy soils, 1 to 2 cultivations will produce a seedbed; • Grow legume crops: Alternatecereal forage crops (oats, barley and millets) with legume forage crops (cowpeas, lab lab, lucerne, snail medic or vetches). Legumes will assist to provide nitrogen for a following cereal crop; • Use adequate fertiliser: Fertilise adequately to grow the forage crop and if there is good soil moisture, fertilise following each grazing: -on soils with reasonable depth, pre-plant with a mixed fertiliser (such as DAP or Crop King 700) to provide around 30 units of nitrogen per hectare, as well as phosphate; and - topdress following each grazing if moisture conditions are good (nitrogen 15 to 20 unitslha). • Grow forage sorghum only on better soils: Forage sorghum requires good nitrogen supplies to grow well. If not fertilised well and conditions are dry, it will take a good deal of nutrients and moisture from the soil. For this reason, this crop is not recommended on granite, traprock and sandstone soils. Black soil paddocks, regularly growing forage sorghum, could be rotated to lab lab every two seasons; • Rotate into pastures: Following 3 to 4 years of forage crop, rotate the paddock into a grass legume pasture for 3 to 4 years to build up nitrogen and organic matter levels. Note: 125 kg!ha or 50 kg!ac Crop King 700 will provide 40 units of nitrogenlha 65 kg/ha or 25 kg!ac Urea will provide 30 units of nitrogen/ha 35 kg/ha or around 15 kg!ac Urea will provide around 15 units of nitrogenlha Example: To calculate units of nitrogen: Urea is 46% N Applying 65 kglha or 25 kg/ac will provide .46 x 65 = 30 units of nitrogen/ha 121 LandPlann ing and Management - Strategies for Sustainability Photo 9.3 An oats crop sod seeded in highly erosive creekflats, Wa rwick For information on growing forage crops, consult the Department of Primary Industries, Darling Downs Crop Management Notes. 9. 7.2 Broadscale fa rming Protecting the soil from erosion Maintain crop stubble standing on the surface (10 to 15 em high) through the fallow (see Figure 9.3). Use one or two herbicide sprays to control weeds, instead of cultivating. Sow crops with planting equipment that can handle stubble. Plant sloping or eroded lands to a pasture for a few years. 122 Land Planning and Management - Strategies for Sustainability 80 Water Runoff 70 60 50 Runoff (m m) ....,._ bare fallo w 40 -zero till 30 20 10 0 15min Time (m inutes) 40min Figure 9.3 A rainfall simulator 'rained' at Warwick at a rate of 75 mm over 45 minutes. This is similar in intensity to a summer storm. Highest runoffwasfrom the bare fa llow (chisel ploughed) plot Photo 9.4 Rainfall simulator, Forest Park, Warwick 123 LandPlann ing and Management - Strategies for Sustainability For more information on reduced tillage contact: DPI Information Centres, Land Care groups or Conservation Farmers Inc, PO Box 838, 132 Cunningham St, Dalby QLD 4405. Phone (076) 624 044. Maintain soil fertility • apply fertiliser to crops in order to produce good yields and maintain soil fertility; • rotate cereal crops such as sorghum, barley and oats with legume crops such as lucerne, mungbeans and soybeans to improve soil nitrogen; • soil test each paddock every 3 to 4 years and fertilise accordingly; • investigate and manage poor performance areas in the case of salinity; • incorporate green manure crops or legume regrowth at the end of a season; and • paddocks could be rotated into permanent pasture for 3 to 5 years between cropping phases to improve soil fertility and structure. Control weeds Weed control in and around paddocks will stop weeds from 'robbing' crops or pastures of moisture, and can help prevent the build-up of insects. Choose herbicides carefully. Chemical residues • when using residual herbicides for weed control in cropping systems, plan future rotations carefully, as low rates of breakdown in dry conditions (and sandy soils) can mean that following crops can be seriously damaged; • always read the label on products and use accordingly; and • some insecticides used have long withholdingperiods before crops can be harvested, grazed or baled. Consider thesecaref ully before applying. Make every possible effort when applying chemicals to reduce the incidence of spray drift. For further information on applying chemicals and sp ray drift: See DPI Crop Management Notes for more information on herbicide choice and residues. DPI Farmnote 'Aerial Spraying' Agdex 688 F7 1. DPI Farmnote 'Spraying Herbicides - landholders obligations' Agdex 688 Flll. DPI Farmnote 'Spraying Herbicides - commercial operators obligations' Agdex 686 F72. DPI Farmnote 'Disposal of unwanted chemicals and empty containers' Agdex 686 F71. 124 Land Planning and Management - Strategies for Sustainability 'Herbicide Application Guidelines' Waggamba Conservation Committee (Landcare), Workshop Proceedings November 1989, QDPI Goondiwindi. Pesticide Application Guidelines, QDPI Information Series QI89003. How to Adapt Machinery to Leave More Stubble Planters: • widen distance between tines; • narrow planting points (better seed placement and poorer weed control); • use planter to plant, not control; • good clearance between tines, from tines to toolbar and to ground wheel; • good depth control better seed placement; and • press wheels. Cultivation equipment: • wide points on tines (for weed control); • good clearance between tines to toolbar and ground wheel; • good distance between tines (30 em); • good clearance from ground to frame; and • good clearance from tine near ground wheel and from ground wheel. Research on Soil Mulches An experiment on soil mulches at DPI' s Heqnitage Research Station has been running for 32 years. The major findings have been: 1. Zero tillage (no cultivation) plus stubble provides more stored water in the soil profile at planting; 2. Retaining stubble results in more soil organic matter and microbes; 3. Zero till plus stubble requires slightly higher rates of nitrogen fertiliser in good years; 4. In very wet seasons, zero till remains better aerated and crops stay greener; 5. Earthworm numbers are greatest under zero till plus stubble; and 6. Zero till, stubble and good nitrogen fertiliser can result in another 0.8 tonneslhectare/year (wheat) compared with leaving no surface stubble and ploughing. 125 LandPlanning and Management - Strategies for Sustainability 9.8 Small holdings management Emma Bryant 9.8.1 Introduction This Manual should be a starting point when determining the characteristics of a plot of land. It outlines for each land type what the land can be used for, what land degradation problems are likely, and what management techniques are required to reduce land degradation. The issue of small holdings management has become more important in recent years, due to high rates of population growth and the fact that more and more people choose small holdings in rural areas as their preferred lifestyle. In the Manual area, the most popular locations for small holdings are near the major centres of Warwick and Stanthor pe. Being located close to centres means that owners can enjoy the benefits of both a rural and town life. However, there are many problems and responsibilities associated with small holdings. A number of publications have been put together in recent times to answer the many questions that owners or potential owners of small holdings have, including the DPI Information Series 'Self-help Landcare fo r new fa rmers ' (Department of Primary Industries 1993) and the Small Holders Education and Development Support Project brochure 'Choosing a small rural block - Is it the life fo r me?'. The information presented in this section has been taken mainly from these sources and they should be referred to for further information. 9. 8.2 Things to consider befo re purchasing Living on a small holding is quite different from living in a town. Listed below are some of the important questions that potential small holders should ask before purchasing: • will living in a rural area meet the goals of all family members? • is the family prepared to be part of a rural community? • do we have the skills and time to manage the holding properly? • what services do we need, for example shops and schools, and how accessible are they? • will existing infrastructure be sufficientor will we be expecting council to upgrade it when they may not be able to, for example gravel roads and lack of town water? • is the block suitable for our purposes, in particular in relation to water supply, soil type, slope, etc.? • what does the local shire plan indicate regarding possible future uses for the block? • will the farming practices of our neighbours cause us concerns? 126 Land Planning and Management - Strategies for Sustainability The last question is particularly relevant in the Manual area. One major problem associated with small holders is that, once they move into a rural area, they realise they do not like some of the activities that occur in agriculture which can be essential to the farmer's enterprises. In the Granite Belt for instance, some small holders who are not horticultural farmers complain about the use of hail cannons and sprays, and this leads to conflictin the community. People moving into an agricultural area should be aware of the seasonal range of activities that commonly occur as a normal part of the agricultural enterprises in the area. 9.8.3 Kn owing the capabilities of the block Every block available for purchase will have unique physical characteristics. It is important that a potential purchaser know these characteristics so that they understand what the block is capable of being used for, and what problems may arise with developing and managing the block. Important characteristics to consider are: • slope - for erosion, crop productivity, machinery, etc.; • aspect - for crop production; • topography - for machinery, roads, fences, dams and crop production; • soil - for productivity and potential land degradation problems; • area/size - for economic potential; • land degradation such as salting and erosion - for productivity; and • water supply, quantity and quality - for domestic use, productivity, fire protection, etc. 9. 8.4 Planning the property A great deal of effort must go into planning the layout of a property if goals are to be achieved and the block maintained. Professional advice should be sought by a landowner if they intend to substantially develop a block. However, some of the main points to consider are: • what are the family's goals and how does our land need to be developed and managed to meet those goals? • do we have the tools to develop a plan, e.g. a map of the property? • what is the best location for particular uses, such as crops? • where are the land degradation problem areas? • where should trees be on the property? • where should buildings, roads and other permanent structures be located on the property? • where should fences and dams go? • how do we incorporate nature conservation? • how do we plan for fires? The DPI, DNR,Landcare groups and consultants provide advice and practical workshops on property planning. 127 LandPla nning and Management - Strategies for Sustainability 9.8.5 Land degradation and protection If land is not managed correctly, then land degradation such as erosion, salinity and weed infestation are likely to result. Not only can land degradation reduce the value and productivity of the property, but it can produce negative effects on neighbouring properties and the environment in general. This Manual provides information on what land degradation problems are associated with which land type, and their prevention and management (see Chapter 8). The main land degradation problems associated with small holdings in the Manual area are: • erosion - most common on the sandstone and traprock land types, particularly when the land is over-grazed, used for unsuitable applications such as cropping, or over-cleared. Over-grazing of land by horses or cattle/sheep/goats is often a problem on small holdings as owners do not realise the carrying capacity of the land; • watercourse degradation - caused by clearing of vegetation, over-grazing, pollutants, and increased water runoff from surrounding land. Small holdings can increase the amount of domestic waste reaching streams, such as detergents and sewerage. It is important to ensure that septic systems are well located and functional. Not all soils are suitable for septic, for example the Cottonvale soils on the granite, which have impermeable clay subsoils, can have problems disposing of wastes; and • pests and weeds - such as cattle tick, fruit fly and lippia. These need to be managed to increase productivity of the block, and also to prevent spreading to adj acent properties. Small holders should consider pest and weed control just as much as full-time farmers. If this is not achieved, then community conflict can occur. For example, in the Granite Belt neglected horticultural crops can harbour pests and diseases which can affect neighbouring properties. 128 Land Planning and Management - Strategies for Sustainability Further Reading Aveyard, J.M. and Sutherland, S.J.M. 1996, 'Agriculture - an important land use in catchments', Journal of Soil Conservation, New South Wales, Soil Conservation Service, NSW, vol. 42 no. 1, pp.51-53. Bourne, G. 1986, Propertydevelopment guidelines fo r the Central Highlands, Queensland Department of Primary Industries Information Series QI86021. Chapman, D.G. and White, K.J. 1993, 'Whole property management planning - an effective group extension strategy', in J. Coutts et al. (comps) Australia Pacific Extension Conference, Surfe rs Paradise, Queensland, Australia, 12-14 Oct. 1994, Dove Rural Media, Newstead, pp.396-399. Department of Primary Industries 1993, Self-help landcare fo r newfa rmers, Queensland Department of Primary Industries Information Series QI93050. Integrated Catchment Management Steering Committee 1991, Integrated catchment management, a strategy fo r achieving the sustainable and balanced use of land, water and related biological resources, Queensland Government. Meyers, R., Kennedy, M. and Sampson, R.N. 1979, 'Information systems for land use planning', in M.T. Beatty, G.W. Petersen and L.D. Swindale (eds), Planning the uses and management of land, Agronomy Series No. 21, American Society of Agronomy, pp.889-907. Molloy, J.M. 1988, Field Manual for Measuring Stubble Cover, Department of Primary Industries, Queensland. Queensland Department of Primary Industries 1990, Guidelines fo r agricultural land evaluation in Queensland, Land Resources Branch, Queensland Department of Primary Industries Information Series QI90005, Brisbane. Reid, T. and Stewart, L. 1993, 'Processes of property management planning workshops - experiences in south-east Queensland', in J. Coutts et al. (comps), Australia PacificEx tension Conference, Surfe rs Paradise, Queensland, Australia, 12-14 Oct. 1994, Dove Rural Media, Newstead, pp.429-434. Roberts, C.J. 1979, 'Principles of land use planning', in M.T. Beatty, G.W. Petersen and L.D. Swindale (eds), Agronomy Series No. 21, American Society of Agronomy, pp.47-63. Small Holders Education and Development Support (SHEDS) Project (unknown), Choosing a small rural block - Is it the life fo r me? Stephens, R.M. and Marshall, J.P. 1986, 'Planning for property development' , Queensland Agricultural Journal, Jul-Aug 1986, vol. 112, no. 4, pp.165-167. 129 130 REFERENCES Ahem, C.R., Shields, P.G., Enderlin, N.G. and Baker, D.E. 1994, Soil Fertility of Central and North East Queensland Grazing Lands, Department of Primary Industries Information Series QI94065, Brisbane. Atkinson, G. 1991, 'Soil Survey and Mapping', in P.E.V. Charman andB. W. Murphy (eds) Soils, Their Properties and Management, Soil Conservation Service of New South Wales, Sydney University Press, pp. 89-111. Baker, D.E. and Eldershaw, V.J. 1993, Interpreting soil analyses fo r agricultural land use in Queensland, Department of Primary Industries Project Report Series Q093014, Queensland. Barrett, G. and Ford, H. 1993, Birds on fa rms: a New England perspective, Greening Australia, Armidale, New South Wales. Bruce, R.C. andRayment, G.E. 1982, Analytical methods and interpretations used by the Agricultural Chemistry Branchfo r soil and land survey, Queensland Department of Primary Industries Bulletin QB82004. Clewett, J.F., Clarkson, N.M., Owens, D.T. and Abrecht, D.G. 1994, Australian Rainman: Rainfa ll Information fo r Better Management, Department of Primary Industries, Brisbane. Dalal, R.C. 1986, 'Cultivation effects on salinity and sodicity ofbrigalow soils in southern Queensland', pp. B5-1 to BS-5, in Landscape, Soil and Water Salinity, Proceedings of the Darling Downs Regional Workshop, Toowoomba, March 1986, Queensland Department of Primary Industries Publications QC86001. Department of Housing, Local Governmentand Planning 1992, State Planning Policy 1192 - Development and Conservation of Agricultural Land, Queensland Departmentof Housing, Local Governmentand Planning, Brisbane. Department of Primary Industries 1993, Self-help landcare fo r new fa rmers, Department of Primary Industries Information Series QI93050, Queensland. Department of Primary Industries and Department of Housing, Local Governmentand Planning 1993, Guidelines: The Identification of Good Quality Agricultural Land, Queensland Department of Primary Industries and Department of Housing, Local Government and Planning, Brisbane. Hazelton, P.A. andMurp hy, B.W. (eds) 1992, What Do All the Numbers Mean? A Guide fo r the Interpretation of Soil Test Results, Department of Conservation and Land Management (incorporating the Soil Conservation Service of NSW), Sydney. Isbell, R.F. 1996, The Australian Soil Classification, (CSIRO Publishing: Melbourne). Lines-Kelly, R. 1994, Soil Sense: Soil Management fo r NSW North Coast Farmers, New South Wales Agriculture, Wollongbar, New South Wales. 131 References Loyn, R.H., Runnalls, R.G., Forward, G.Y. and Tyers, J. 1983, 'Territorial bell miners and other birds affecting populations of insect prey', Science, vol. 221, pp. 1411-1413. Loyn, R.H. 1987, 'Effect of patch area and habitat on bird abundances', in D.A. Saunders et al. (eds) Nature Conservation: The Role of Remnants of Native Vegetation, Surrey Beatty and Sons Pty Ltd, Chipping Norton, New South Wales, pp. 65-75. Rengasamy, P. and Walters, L. (comps) 1994, Introduction to soil sodicity, Cooperative Research Centre for Soil and Land Management, Australia, Technical note 1. Rosser, J., Swartz, G.L., Dawson, N.M. and Briggs, H.S. 1974, A land capability classification fo r agricultural purposes, Division of Land Utilisation, Technical Bulletin No. 14, Queensland Department of Primary Industries. Shields, P.G. and Anderson, E.R. 1989, The soilfertility of Capricorniagrazing lands, Queensland Department of Primary Industries Project Report Q089025, Brisbane. Silburn,D.M., Carroll, C., Ciesiolka, C.A.A. and Hairsine, P. 1992, ' Management Effects on Runoff and Soil Loss from Native Pasture in Central Queensland', Conference papers: Australian Rangeland Society 7th Biennial Conference 'Australian rangelands in a changing environment', Australian Rangeland Society, 5-8 October 1992, Cobar, New South Wales. Soil Pit Field Day 1992, Southern Hills Soil Conservation Board, South Australia. Stanthorpe Shire Council 1996, Planning Scheme, Stanthorpe Shire Council, Queensland. Tothill, J.C. and Gillies, C. 1992, The pasture lands of northernAu stralia. Their condition, productivity and sustainability, Occasional Publication No. 5, Tropical Grassland Society of Australia. Voller, P.J. and Molloy, J.M. (comps) 1993, Points to consider before clearing land in south Queensland, Queensland Department of Primary Industries, Brisbane. Wills, A.K. 1980, Granite Belt soil erosion survey, Division of Land Utilisation, Report 80/5, Queensland Department of Primary Industries. 132 APPENDIX 1 A list of plants commonly found in the Stanthorpe-Rosenthal region Scientific name Common name Acacia adunca mountain wattle Acacia fa lciformis wattle Acacia implexa lightwood Acacia leiocalyx Brisbane black wattle Acacia leucoclada subsp. argentifolia wattle Acacia neriifolia wattle Acacia ruppii Acacia salicina sally wattle Acacia spp. green wattle Allocasuarina luehmannii bull oak Alphitonia excelsa red ash Andropogon virginicus broomsedge Angophora costata smooth barked apple Angophora floribunda rough barked apple Angophora leiocarpa rusty gum Angophora subvelutina broadleaf apple Archidendropsis basaltica dead finish Aristida spp. wiregrass Arundinella spp. reedy grass Banksia spp. banksia Boronia amabilis boronia Boronia granitica boronia Boronia repanda boronia Cadellia pentastylis ooline Callitris endlicheri black cypress pine Callitris glaucophylla white cypress pine Callitris monticola cypress pme Cassinia laevis coughbush Cassinia quinquefa ria coughbush Casuarina cunninghamiana river sheoak Cheilanthes sieberi rock fern Cymbopogon refractus barbwire grass Dendrocnide excelsa giant-leaved stinging tree Dichanthium sericeum Queensland bluegrass Dodonaea spp. hopbush Dodonaea viscosa sticky hopbush 133 Appendix 1 A list of plants commonly found in the Stanthorpe-Rosenthal region Scientific name Common name Eucalyptus albens white box Eucalyptus andrewsii New England blackbutt Eucalyptus banksii Tenterfield woollybutt Eucalyptus biturbinata grey gum Eucalyptus blakelyi Blakely's red gum Eucalyptus bridgesiana apple box Eucalyptus caleyi Caley's ironbark Eucalyp tus caliginosa broad leaved stringybark Eucalyp tus camaldulensis river red gum Eucalyptus camphora mountain swamp gum Eucalyp tus conica fuzzy box Eucalyp tus crebra narrow leaved ironbark Eucalyp tus dalrympleana mountain gum Eucalyptus dealbata tumbledown gum, hill gum, mountain gum Eucalyptus deanei Deane's gum, round leaved gum Eucalyptus fi brosa subsp. nubila bluetop ironbark, dusky leaved ironbark Eucalyptus laevopinea silvertop stringybark Eucalyptus maculata spotted gum Eucalyp tus magnificata eucalypt Eucalyp tus melanophloia silver leaved ironbark Eucalyptus melliodora yellow box Eucalyptus microcarpa grey box Eucalyptus moluccana gum topped box, grey box Eucalyptus nova-anglica New England peppermint Eucalyptus obliqua messmate stringybark Eucalyp tus pauciflora snow gum Eucalyp tus pilligaensis mallee box Eucalyptus populnea poplar box Eucalyptus prava orange gum Eucalyptus radiata narrow leaved peppermint Eucalyptus saligna Sydney blue gum Eucalyptus sideroxylon mugga, red ironbark Eucalyptus tereticomis blue gum Eucalyptus viminalis manna gum Eucalyptus youmanii Youman's stringybark Grevillea juniperina grevillea Grevillea scortechinii grevillea Heliotropium amplexicaule blue heliotrope, wild verbena Homoranthus papillatus homoranthus Hymenanthera dentata hymenanthera 134 Appendix 1 A list of plants commonly found in the Stanthorpe-Rosenthal region Scientific name Common name lmperata cylindrica blady grass Jacksonia scoparia dogwood Leptospermum attenuatum wild may Leptospermum brevipes wild may Leucopogon melaluecoides leucopogon Leucopogon muticus leucopogon Macrozamia viridis zamia palm Olearia elliptica sticky daisy bush Persoonia daphnoides geebung Phyla canescens lippia Pimelea neo-anglica rice flower Pittosporum phylliraeoides weeping pittosporum Pteridium esculentum bracken fern Pterostylis woolsii long tailed greenhood Rubus fruticosus blackberry Sclerolaena birchii galvanised burr Wahlenbergia spp. bluebells 135 136 APPENDIX 2 Ratings used for interpretation of soil analyses Ratings Soil Test Unit Very low Low Medium High Very high Cl (%) <0.01 0.01-0.03 0.03-0 .06 0.06-0.20 >0.20 PACID (mg/kg) <10 10-20 20-40 40-100 >100 PsiCARB (mg/kg) <10 10-20 20-40 40-100 >100 Extr. K (m.eq%) <0. 1 0.1-0.2 0.2-0.5 0.5-1 .0 >1.0 Cu (mg/kg) <0.1 0.1-0.3 0.3-5 5-1 5 >15 Zn pH>? (mg/kg) <0.3 0.3-0.8 0.8-5 5-15 >15 pH15 Mn (mg/kg) <1 1-2 2-50 50-500 >500 Total N (%) <0.05 0.05-0.15 0.1 5-0.25 0.25-0.5 >0.5 (%) Total P <0.005 0.005-0 .02 0.02-0.05 0.05-0.10 >0.10 (%) Total K <0.1 0.1-0.5 0.5-1 .0 1.0-3.0 >3.0 (%) Total S <0.005 0.005-0.02 0.02-0.05 0.05-0.10 >0.10 (mm) PAWC <50 50-100 100-1 50 150-200 >200 Dispersion <0.6 0.6-0.8 >0.8 ratio pH extremely acid <4.5 very strongly acid 4.5-5.0 strongly acid 5.1-5.5 medium acid 5.6-6.0 slightly acid 6.1-6.5 neutral 6.6-7.3 mildly alkaline 7.4-7.8 moderately alkaline 7.9-8.4 strongly alkaline 8.5-9.0 very strongly alkaline >9.0 137 138 APPENDIX 3 Analytical data for example soil profiles This appendix contains both the detailed description and the analytical data for 18 soils. The soils selected for analysis are representative of the range of soils within a given soil group. Each group is given a local name to aid communication concerning a given soil. Soil profile samples have been taken from virgin sites to provide an indication of 'base-line' nutrient levels. However, some were taken from farmed paddocks to give an indication of their condition under current management practices. The methods used for soil physical and chemical analyses are detailed in Baker and Eldershaw (1993). A detailed explanation of the terms used in the Australian Soil Classification system can be found in Isbell (1996). It should be noted that the cation exchange capacity (CEC) method at pH 8.5 will overestimate CEC for acid layers e.g. acid surface soils over alkaline subsoils. 139 Appendix 3 Analytical data for example soil profiles ALLAN EXAMPLE SOIL PROFILE SOIL GROUP: Allan SUBSTRATE MATERIAL: Sandstone SITE NO: Site 15 LOCATION: Railway cutting, Sandy Creek Rd., Leslie SLOPE: 5% AMG REFERENCE: 393 000 mE, 6 883 000 mN, Z56 LANDFORM ELEMENT TYPE: Midslope GREAT SOIL GROUP: Sol odic LANDFORM PATTERN TYPE: Undulating rises PRINCIPAL PROFILEFORM: Dy2. 13 VEGETATION: AUSTRALIAN SOIL CLASSIFICATION: Calcic, Subnatric, Brown STRUCTURAL FORM: Dry open forest Sodosol DOMINANTSPECI ES: Eucalyptus populnea, E. microcarpa PROFILE MORPHOLOGY CONDITION OF SURFACE SOIL WHEN DRY: Hard setting HORIZON DEPTH (m) DESCRIPTION AI 0.00 to 0.15 Dark yellowish brown (lOYR 4/4) sandy clay loam; few medium quartz pebbles; moderate, 5-10 mm, angular blocky structure; clear change to - B2 0.15 to 0.65 Yellowish brown (lOYR 5/8) fine sandy medium clay; strong, 20-50 mm, angular blocky structure; few manganiferous veins; gradual change to - BIC 0.65 to 1.10 Brownish yellow (IOYR 6/6) clay loam, coarse sandy; massive; fe w manganiferous veins; calcareous soft segregations common. LABORATORY DATA Depth pH EC Cl Particle Size (%) Exch. Cations (m.eq/1 OOg)' ESP Total Elements (%) Moisture (%) Dispersion (m) (dS/m) (%) cs FS Si c CEC Ca'· Mg'' Na· K' % p K s Ratio ' 33* 1500* s'o -1o 7.0 0.03 0.002 : ·······---�.: ...... ·--�----. ···--·� ...... ·---�...... ·----�---...... � ...... �-.... ····-�--...... � ...... -�---...... :...... -�.. . :... L � L � ...: l ...... -----�-----L�:� ...��-: ... 1 ...� :�:.. .l .� ��-�-- ...... L . . ------�-:-�-�------...� .. �-- �-- ��-��-- � .. ... ��--- � . . L.:.:...... � �------���-�----··· . 1 l �:��-L�--��-- ·----��-�---- ..� :��.:- --.. l ...... ------��-:-�-�---·-- ---�·.:... L�- -��--1--���-��-- --��---l---��---l----�----1...��------��----l..�:�--1---��-�--.L�:� . ..l.-����-- --�-��-�--- --���� ��-- ���:...... �.: ..... ------��:-�...... 50 ·60 9.2 : 0.41 : 0.023 28 : 22 : 5 : 46 32 : 15 : 12 : 5.0 : 0.19 15.6 0.027: 1..�l 1.: 07 L�0.042 . . ) 15 0.67 ------···· ------·· ------··------·--· ---· ------·· ------l -- -- ...... l --·- · ------�� :�� �-� : �-�� : �:��; ;� -� �� -r �� 1" �� �; � �:� � �; - : ;:� � �;� �:��; : ;:�; � �:�;; . � ;� �:�� ·-- ·- - · ·· ------·-- ·- -- ·· · · -- ··------·----· ·------· ·········· ·-·------·-- ·· ··------·--;�-�---· ------··· ···----···· ···--·------·····------...... - - ...... ; �� : ; ;� �� t �;� �:�;; r r t ;� r �:� r �-� t �:; r � ;� ;;� t t r . J. . : . : . . . : : : Depth Organic C Total N Extractable P (mg/kg) mg/kg Extractable Fe Mn Cu Zn K (m) (%) (%) Acid Bicarb. S04-S (meq%) DTPA-extractable (mg/kg) B' 0 ·0.10 1.2 0.06 13 11 4.0 0.35 16 43 0.19 2.7 ' aqueous cations at pH 7.0 • -33kPa (-0.33bar) and -1500kPa (- 15 bar) using pressure plate apparatus ' refers to the bulking of a number of surface samples prior to analysis 140 Appendix 3 Analytical data fo r example soil profiles BANCA EXAMPLE SOIL PROFILE Not at photographed site SOIL GROUP: Banca SUBSTRATE MATERIAL: Herries Adamellite SITE NO: Site A151 @ LOCATION: Near Ironpot Creek SLOPE: 6-10% AMG REFERENCE: 388 750 mE, 6 870 500 mN, Z56 LANDFORM ELEMENT TYPE: Midslope GREAT SOIL GROUP: Siliceous sand - earthy sand intergrade LANDFORM PATTERN TYPE: Low hills PRINCIPAL PROFILE FORM: Uc2.21 VEGETATION: AUSTRALIAN SOIL CLASSIFICATION: Basic, Paralithic, Bleached STRUCTURAL FORM: Open forest Orthic Tenosol DOMINANT SPECIES: Eucalyptus crebra, Xanthorrea spp. PROFILE MORPHOLOGY CONDITION OF SURFACE SOIL WHEN DRY: Loose HORIZON DEPTH (m) DESCRIPTION Al 0.00 to 0. 10 Black (lOYR 311) sandy clay loam, coarse sandy; massive; very friable A2 0. 10 to 0.20 Brown (7.5YR 5/4) conspicuous bleach when dry, sandy clay loam, coarse sandy; massive; very friable B21 0.20 to 0.45 Reddish yellow (7.5YR 6/6) coarse sandy clay loam; massive; very friable B22 0.45 to 0.90 Yellowish brown (lOYR 5/6) loam, coarse sandy; massive; very friable LABORATORY DATA Depth pH EC Cl Particle Size (%) Exch. Cations (m.eq/100g)' ESP Total Elements (%) Moisture (%) Dispersion (m) (dS/m) (%) cs FS Si c CEC Ca'' Mg" Na' K' % p K s 33* 1500* Ratio ...... �:� ... ..�. -�� . .L.�:���---...�.� ...... �� .. . �.�---· .....� ...... ; ...�--� ... l..�:��. .t..�---�� ...... � ...... � ...... � --�:�.� .. .. l . ;..... � .... l. . l . �:� ...... �:��-� -�:��...... �:� ... l..�:-��--L�:.���---...... l ...... l ...... l...... l...... l ...... L .l. . ! . . . . . L ..! ...... �:��-�-�:�� ...... �:� ... l ..�:�� ..l- -�:-���---·--�-� ... l----�� ...... �� ...... �:� ...:. ..�--� ..�: ��-.l.. �- :-�------�------...... L � L - .....� .. . 1 ... l . . L ..l . t ...... �:��- .-..�:��- ...... �:� ... .�:��.. ..�:��� ...... + ...... 0.45 . 0.60 6.2 0.14 0.001 53 22 4 21 6 4.0 1.0 0.18. 0.13 3 �! . -�! �! . -t! ...... �.....! ...... t..! ! ...... t! ... . l...... ! ...... 1 ! ...... t.. ! ...... l....! ...... -- ...... -����-:·���� .. -.. -�--�---r--�.-;�-r�-��;--· . �; ...... �----r·-�;---- l·-�:�·-r··;·_·;·--r�:��-r-�·;; - ...... r r ...... �;- --r l-- � . � 1 ...... Depth Organic C Total N Extractable P (mg/kg) Extractable K Fe Mn Cu Zn (m) (%) (%) Acid Bicarb. (meq%) DTPA-extractable (mg/kg) 0-0.10 0.70 0.07 5.0 • From Wills, A.K., 1976. ' aqueous cations at pH 7.0 * -33kPa (-0.33bar) and -1500kPa (- 15 bar) using pressure plate apparatus 141 Appendix 3 Analytical data fo r example soil profiles BONNIE DOON EXAMPLE SOIL PROFILE SOIL GROUP: Bonnie Doon SUBSTRATE MATERIAL: Sandstone SITE NO: Site 9 LOCATION: 'Bonnie Doon' SLOPE: 5% AMG REFERENCE: 358 000 mE, 6 896 400 mN, Z56 LANDFORM ELEMENT TYPE: Midslope GREAT SOIL GROUP: Soloth LANDFORM PATTERN TYPE: Undulating rises PRINCIPAL PROFILE FORM: Dy3.41 VEGETATION: AUSTRALIAN SOIL CLASSIFICATION: Bleached-Mottled, Natric, STRUCTURAL FORM: Open forest (mostly cleared) Grey Kurosol DOMINANT SPECIES: Eucalyp tus populnea, E. tereticomis, E. crebra, Callitris glaucophylla, Angophora leiocarpa, Cassinia laevis. PROFILE MORPHOLOGY CONDITION OF SURFACE SOIL WHEN DRY: Hard setting HORIZON DEPTH (m) DESCRIPTION Al 0.00 to 0.15 Dark brown (lOYR 3/3) sandy loam; massive; weak consistence dry; clear change to - A2e 0. 15 to 0.55 Yellowish brown (lOYR 5/6 moist, lOYR 7/2 dry) conspicuous bleach, loamy coarse sand; massive; firm consistence dry ; abrupt change to - B21 0.55 to 0.85 Greyish brown (lOYR 5/2) coarse sandy light medium clay, with many distinct mottles; massive; firm consistence dry ; clear change to - B22 0.85 to 1.00 Light greyish brown (lOYR 612) coarse sandy medium clay, with abundant prominent coarse orange mottles; very few coarse quartzgrav els; weak, 20-30 mm, angular blocky structure; strong consistence dry; clear change to- R 1.00+ Weathered sandstone. LABORATORY DATA ' Depth pH EC Cl Particle Size (%) Exch. Cations (m.eq/100g) ESP Total Elements (%) Moisture (%) Dispersion (m) (dS/m) (%) cs FS Si c CEC Ca'" Mg'" Na" K' % p K s 33* 1500* Ratio B1 0 -0.10 6.0 : 0.02 : 0.003 ····················· ...... ;...... ;...... ;...... ;...... � ...... ;...... � ...... :...... ;...... ;...... ····················· ...... ;...... ;...... ...... ······· ...... �.��..l .. ���.�� ...... l . . ��...... �.� ... �. · ··· ...... i.�:�:...l ...... ���.�� .. . .L.�:��.� ..... � ...... ���.�...... �:�� �. . �� . � ....� ::� �::.:... .. �: ... L�::.:.� 20 . 30 6.1� l: 0.01 : 0.002 60 : 27 l: 5 L..: 7 1: ..0.32 �:�...\ : 0.33 : 0.01 : 0.10 0.008 : 0.637 : ·0.006...... 1 : 0.94 . . ·······! ...... ···· ········· ·· ····· ..... ·········· ..... ····· ·········· ...... ·······. ·· ...... ·········· ····· ...... ·· ...... - ···...... -� . � :- + � ! :- :- ...... -� . . . :- � ...... ...... �� .:.�.� ...... L�.. �� . . . ���.�� ...... L .. . l .. ··· ...... �. � ..�:�� ...... l ...... � � .i . �� .. . . �� � L.�:��. l . ... l .L�:.:� ...... �:� ...... l ...... L...... 90 - 100 5.4 j 0.03 j 0.004 49 .L.j .��10 j 4� j 35 8 j 0.13 j 3.3 j 0.45 j 0.27 5.6 j j j Depth Organic C Total N Extractable P (mg/kg) Extractable K Fe Mn Cu Zn (m) (%) (%) Acid Bicarb. (meq%) DTPA-extractable (mg/kg) B1 0-0.10 1.3 0.09 7.0 11 0.29 57 20 0.37 5.0 ' aqueous cations at pH 7.0 * -33kPa (-0.33bar) and -1500kPa (-15 bar) using pressure plate apparatus ' refers to the bulking of a number of surface samples prior to analysis 142 App endix 3 Analytical data for example soil profi les COTTONVALE EXAMPLE SOIL PROFILE SOIL GROUP: Cottonvale SUBSTRATE MATERIAL: Granite SITE NO: Site 17 LOCATION: Church Rd., The Summit SLOPE: 5% AMG REFERENCE: 396 800 mE, 6 838 100 rnN, Z56 LANDFORM ELEMENT TYPE: Upper slope GREAT SOIL GROUP: Yellow podzolic LANDFORM PATTERN TYPE: Low undulating hills PRINCIPAL PROFILE FORM: Dy3.41 VEGETATION: Cleared AUSTRALIAN SOIL CLASSIFICATION: Bleached-Mottled, STRUCTURAL FORM: Magnesic-Natric, Grey Kurosol DOMINANT SPECIES: PROFILE MORPHOLOGY CONDITION OF SURFACE SOIL WHEN DRY: Hard setting HORIZON DEPTH (m) DESCRIPTION AI 0.00 to 0.15 Dark brown (7.5YR 3/2) coarse sandy clay loam; moderate, granular structure; gradual change to - A2e 0.15 to 0.40 Light yellowish brown (2.5Y 6/3 moist, 2.5Y 7/4 dry) conspicuous bleach, coarse sandy loam; moderate, 2-5 mm granular structure; abruptchange to - B21 0.40 to 0.65 Grey (7.5YR 611) coarse sandy light medium clay, with many, very coarse prominent orange mottles; moderate, 20-50 mm, angular blocky structure; gradual change to - B22 0.65 to 1.00 Grey (7.5YR 6/1) coarse sandy light clay, with many, very coarse prominent orange mottles; massive. LABORATORY DATA Depth pH EC Cl Particle Size (%) Exch. Cations (m.eq/100g)' ESP Total Elements (%) Moisture (%) Dispersion (m) (dS/m) (%) cs FS Si c CEC Ca'· Mg'· Na· K. % p K s 33* 1500* Ratio 81 0 ·0.10 6.3 i 0.04 i 0.004 ...... ;...... ,:...... �--··· ..... �--...... ;...... -�--.... ···-�---...... :...... �...... : ...... :...... ········ ...;...... ...... �.:.:.� ...... ��� ... l ..��.�� .. t ..� ��� ··· ...�.� ...L ��... t ....� . .. . t ... �.� ··· ....� . .... i ...: ..: ... l ...::� .. J..����...... � ...... �·.�.:� .. ...�·.�� ... .. �:�.�� ...... l ..... � ...... �:�. ······· · � .i..�·.�.� ! ! � .....�� . . .�� ······ ...��� ...... ���··· ...... � ...... � .. �� ...... � ... �� ...... �:�.�� . .\ ... �·.�.: ...\. .�:�.�� ...... � .�······· l ..���� L �� :� ... l �.� l L. � l l.����.. .L.�:�� l :.� 1 � :� ·····�� · ·�� ······ ···:� ······ :·:�··· ..� · �:: ·· ···::········�:········�·····.. · �: ··· ····:·······� ·�� ······:· �······:· :: ·····� ·�� ·· ····�: ···· ··�·�·�� ······::� ······�· ��·· ·················�·� ···· ...... � .:·�··· .... : : : .- : Depth Organic C Total N Extractable P (mg/kg) Extractable K Fe Mn Cu Zn (m) (%) (%) Acid Bicarb. (meq%) DTPA·extractable (mg/kg) B' 0 ·0.10 2.1 0.12 11 22 0.59 84 16 0.60 6.2 ' aqueous cations at pH 7.0 * -33kPa (-0.33bar) and -1500kPa (- 15 bar) using pressure plate apparatus 1 refers to the bulking of a number of surface samples prior to analysis 143 Appendix 3 Analytical data for example soil profiles DALVEEN EXAMPLE SOIL PROFILE SOIL GROUP: Dalveen SUBSTRATE MATERIAL: Sandstone SITE NO: Site 10 LOCATION: Bisley St., Warwick SLOPE: 3% AMG REFERENCE : 403 300 mE, 6 876 750 mN, Z56 LANDFORM ELEMENT TYPE: Hillslope GREAT SOIL GROUP: Solodic LANDFORMPATTERN TYPE: Rise PRINCIPALPROFILE FORM: Dy4.22 VEGETATION: AUSTRALIAN SOIL CLASSIFICATION: Haplic, Eutrophic, Brown STRUCTURAL FORM: Open forest Chromosol DOMINANT SPECIES: Eucalyptus tereticomis, E. microcarpa, E. conica, Acacia spp. PROFILE MORPHOLOGY CONDITION OF SURFACE SOIL WHEN DRY: Loose HORIZON DEPTH (m) DESCRIPTION All 0.00 to 0.10 Dark brown (7 .5YR 3/2) sandy clay loam; weak, 2-5 mm,granular structure; few medium angular pebbles; clear change to - Al2 0. 10 to 0.20 Dark brown (lOYR 3/3) sandy clay loam; fe w medium rounded quartz pebbles; massive; gradual change to A2 0.20 to 0.40 Light yellowish brown (!OYR 4/4 moist, lOYR 6/4 dry) sandy loam; massive; many large, rounded quartz and sandstone pebbles; abrupt change to - B21 0.40 to 0.70 Yellowish brown (lOYR 5/8) medium clay, with few faint red mottles; weak, 10-20 mm, subangular blocky structure; moderately firmconsistence; clear change to - B22 0.70 to 0.90 Yellowish brown (lOYR 5/8) coarse sandy medium clay, with few medium red and grey mottles; weak, 10-20 mm, subangular blocky structure; moderately firmconsistence; gradual change to - c 0.90 - Clayey coarse sand. LABORATORY DATA Depth pH EC Cl Particle Size (%) Exch. Cations (m.eq/1 DOg)' ESP Total Elements (%) Moisture (%) Dispersion (m) (dS/m) (%) cs FS Si c CEC Ca'· Mg'· Na· K" % p K s 33* 1500* Ratio 1 B 0 ·0.10 6.7 i 0.05 0.02 ····················· ·········-+·········-�·-··········i ········-�·-········ �--·······-�·-········ ·········-�·-·······-�·-·······-�---·······�·-·········· ...... ···········-�·-··········�·-·········· ···········-�---········· ...... 0-10 6.5 0.05 0.02 42 37 4 16 6 4.0 1.8 0.11 0.54 2 0.044 0.926 0.025 5 0.46 i i i . . i i i . . i i .i .. .. i ...... i ...... i ...... :...... �--...... � .. . . � ...... :...... -� ...... � ...... L .. .. L...... i. . ..� ...... 1...... ��.: .�.�---··· ...:..� ... L�:.�� ..l ...����- -- ·--�� ..L.��---1 ...... � �� ...... �. . · .... � .... . � . . ..::� .l ...�:�� --- ...... -- �- � . ..�::��- -l ..�:��-: ...... � -�---···· 50 .60 6.7 0.05 0.04 28 17 4 53��--- 11 5.2 4.6 0.27 0.62 2 0.030 0.785 0.013 14� 0.34� i i i i .... 1i .Li . ..L i .�:.� ... l.i .�:.�: i . . . � . 1i i 1i ...... ·····-��·:·�-�-····· ·--�-�-··r·�--��--1···�:�-�--- --��-··r··��···r··�···-r··�;···· ·---��---r .�: �···!···��-··r··�:��·r··�--��--- ····;···· ··�:�;-�··r�:;�;··r··�--���- ···········r··-��···· ·······�:�······· Depth Organic C Total N Extractable P (mg/kg) Extractable K Fe Mn Cu Zn (m) (%) (%) Acid Bicarb. (meq%) DTPA-extractable (mg/kg) B1 0·0.10 1.5 0.10 38 15 0.65 23 84 0.32 3.1 • aqueous cations at pH 7.0 * -33kPa (-0.33bar) and -1500kPa (-15 bar) using pressure plate apparatus ' refers to the bulking of a number of surface samples prior to analysis 144 Appendix 3 Analytical data for example soil profiles DROME EXAMPLE SOIL PROFILE SOIL GROUP: Drome SUBSTRATE MATERIAL: Sandstone SITE NO: Site 11 LOCATION: Stonehenge Rd., west of Leybum SLOPE: <1% AMG REFERENCE: 355 600mE, 6 898 400mN, Z56 LANDFORM ELEMENT TYPE: Mid to upper slope GREAT SOIL GROUP: Siliceous sand LANDFORM PATTERN TYPE: Undulating rises PRINCIPAL PROFILEFORM: Ucl.22 VEGETATION: AUSTRALIAN SOIL CLASSIFICATION: Basic, Arenic, Orthic STRUCTURAL FORM: Open fo rest (disturbed) Tenosol DOMINANT SPECIES: Callitris glaucophy/la, Angophora leiocarpa, Eucalyptus tereticornis, Banksia integrifo lia PROFILE MORPHOLOGY CONDITION OF SURFACE SOIL WHEN DRY: Loose HORIZON DEPTH (m) DESCRIPTION 01 0.00 to 0.02 Organic debris; abrupt change to - All 0.02 to 0.15 Brown (lOYR 5/3) sandy loam; weak, 2-5 mm, granular structure; very weak consistence dry; many fine roots; clear change to - A12 0.15 to 0.60 Brownish yellow (lOYR 6/6) loamy sand; single grain; gradual change to - B21 0.60 to 1.00 Brownish yellow (IOYR 6/6) loamy sand, with very few medium red mottles; single grain; gradual change to B22 1.00 to 1.20 Brownish yellow (IOYR 6/6) sandy loam, with common red mottles; single grain. LABORATORY DATA Depth pH EC Cl Particle Size (%) Exch. Cations (m.eq/1 OOg)' ESP Total Elements (%) Moisture (%) Dispersion (m) (dS/m) (%) cs FS Si c CEC Ca'· Mg'· Na· K" % p K s 33* 1500* Ratio 1 B 0 ·0.10 5.6 � 0.04 � 0.003 . ••• •• •••••••• •••• ••• •••••••••• � .•.••.• ---�---.. ·····-..•••••• --�-•••••• ·--�---· ••.•••• �-----····· •••••••••.; .••••••••• � •••.... ·--� •.•••••.•.; . •.••.•••••• • •••••••.. ••.•...•••••j ••••••••.... ; ---· ..•••••• • ••••.• -----� .... ·-··.. .. • •••..•....•.....••. 0-10 5.8 l 0.02 l 0.002 60 l 34 l BD l 5 l 0.59 l 0.40 l 0.05 l 0.12 5 0.020 l 0.118 l 0.011 l 0.10 ...... �--······.. �-- ...... -� ...... �-- ...... ·f····· ...... ·: ······· . .. � ...... +········.. � ···...... ; ...... : ...... -�...... --- � - ---···· ..... ��-- - �---··· ...�:� ---�--�--��---�--�--���---·--�-�---l---�� ...... ---·� ·-·· ·--�-� ...\ . . �--�� .. ..� �--�- -��� .. \ . �--��--- ·········· --�---�-��.. \ .. ���.:� .. \ . ���-��-- ...... � �� �� t � � ; :� : ...... ; � - ·-- - ...... ·-- - ...... � - ---···· .....�� -�-��---··· ...�:� ..�:.� � �: ��- �� . . . . . �� . � .:� ..�:��-.l ...�-- ��--- ...... --�--�-�� . .l . . ���-��-- ...... ��� ...l ... l .. - L..�� l . � . l .. l . .L.�:��--l . ���.:� .. l ...... [ . . . � -� - � ···· �····.. � - �······�-���··· ·-- - ...... ---····· ·-············· ·············� -�� ····· · �� ·····�-�� ··•···� -� --- ···· · -- -- . - . ···· ··· · � �� �� � ���� ... ����� .. �� -��-- ...... , ...... ���-�---···· ;� : � : :: . : : : > - . .. Depth Organic C Total N Extractable P (mg/kg) Extractable K Fe Mn Cu Zn (m) (%) (%) Acid Bicarb. (meq%) DTPA-extractable (mg/kg) B1 0-0.10 0.76 0.02 10 15 0.12 47 15 0.05 0.74 ' aqueous cations at pH 7.0 BD below limits of detection * -33kPa (-0.33bar) and -1500k.Pa (- 15 bar) using pressure plate apparatus 1 refers to the bulking of a number of surface samples prior to analysis 145 Appendix 3 Analytical data for example soil profi les GAMMIE EXAMPLE SOIL PROFILE SOIL GROUP: Gamrnie SUBSTRATE MATERIAL: Traprock SITE NO: Site 13 LOCATION: Pikedale, road cutting SLOPE: 5% AMG REFERENCE: 367 980 mE, 6 830 900 mN, Z56 LANDFORM ELEMENT TYPE: Hillslope GREAT SOIL GROUP: Lithosol LANDFORM PATTERN TYPE: Low rolling hills PRINCIPALPROFILE FORM: Um2. 12 VEGETATION: AUSTRALIAN SOIL CLASSIFICATION: Basic, Paralithic, Bleached STRUCTURAL FORM: Woodland Leptic Tenosol DOMINANT SPECIES: Eucalyptus spp., Acacia spp. PROFILE MORPHOLOGY CONDITION OF SURFACE SOIL WHEN DRY: Hard setting HORIZON DEPTH (m) DESCRIPTION AI 0.00 to 0.10 Dark brown (lOYR 3/3) clay loam; massive; few angular gravel; firm consistence dry; gradual change to A2e 0.10 to 0.20 Yellowish brown (!OYR 5/6 moist, lOYR 8/3 dry) conspicuous bleach, clay loam; many angular gravels; massive; firm consistence dry ; gradual change to - B3 0.20 to 0.40 As above, interspersed with weathered rock; gradual change to - R 0.40 + Rock LABORATORY DATA Depth pH EC Cl Particle Size (%) Exch. Cations (m.eq/100g)' ESP Total Elements (%) Moisture (%) Dispersion (m) (dS/m) (%) cs FS Si c CEC Ca'· Mg'· Na· K" % p K s 33* 1500* Ratio B'O ·0.10 6.8 : 0.02 : 0.001 ...... ··········+ ··········�---········· ·········� ---········: ··········+ ·········· ··········+ ··········:··········r··········:- ··········· ...... ············+ ············�············ ·········-··-: ············ ...... ...... � .:. .�······· ...... l..�.. �� .. ! .. ���.�� . ... �� .. L..�� ... L ..�� .... L . �� ··· .... � .... 1 . ..�:� ... 1 ... L.�:��-L.�:��.. . ·--��---· .. ���-�� .. i.... �: �:... .L.�:.���--· ...... l. . ... � ...... � :�.�········ � �.� . ...�.- � 1 ...... �·-···· ...... ···· ...... - -·· ...... ·-······ :�:� :..�.. L�:.�� . �:�.�-�-- .�� .. �� . �� L �� ... �:� . .�: �� .. �:�� . . �·.�.:� L�:..� �:���··· . .. :. �:�� 50 . 60 5.6 j 0.04. .ij 0.005 21 lj 10 l: 35 j 35 :.4.... 1: 0.51 ..!j 2.9�:-� i: 0.30 :l 0.11 8 0.019 : 3.35.. .l: 0.006 Lj ..8 0.74 Depth Organic C Total N Extractable P (mg/kg) Extractable K Fe Mn Cu Zn (m) (%) (%) Acid Bicarb. (meq%) DTPA·extractable (mg/kg) s' o -o.1o 1.4 0.10 31 24 0.83 20 19 0.27 0.99 ' aqueous cations at pH 7.0 * -33kPa (-0.33bar) and -1500kPa (-15 bar) using pressure plate apparatus ' refers to the bulking of a number of surface samples prior to analysis 146 App endix3 Analytical data for example soil profiles GLENTANNA EXAMPLE SOIL PROFILE SOIL GROUP: Glentanna SUBSTRATE MATERIAL: Traprock SITE NO: Site 16 LOCATION: Glentanna Rd, Scottsdale SLOPE: 6% AMG REFERENCE: 393 500 mE, 6 852 500 mN, Z56 LANDFORM ELEMENT TYPE: Midslope GREAT SOIL GROUP: Non-calcic brown soil LANDFORM PATTERN TYPE: Rolling hills PRINCIPAL PROFILE FORM: Dbl. l2 VEGETATION: Cleared AUSTRALIAN SOILCLASSIFICATION: Haplic, Eutrophic, Brown STRUCTURAL FORM: Chromo sol DOMINANT SPECIES: PROFILE MORPHOLOGY CONDITION OF SURFACE SOIL WHEN DRY: Hard setting HORIZON DEPTH (m) DESCRIPTION AI 0.00 to 0.15 Dark brown (7 .SYR 3/2) sandy clay loam; weak, 2-5 mm, subangular blocky structure; abundant angular, large pebbles; clear change to - B21 0.15 to 0.35 Brown (7 .SYR 4/4) light medium clay; strong, 5-10 mm, subangular blocky structure; few medium sized pebbles; gradual change to - B22 0.35 to 0.60 Brown (10YR 4/3) medium clay; strong, 20-50 mm, angular blocky structure; few medium si7£d pebbles; clear change to - c 0.60 to 1.10 Clay pockets in weathered traprock. LABORATORY DATA Depth pH EC Cl Particle Size (%) Exch. Cations (m.eq/100g)' ESP Total Elements (%) Moisture (%) Dispersion (m) (dS/m) (%) cs FS Si c CEC Ca'· Mg'' Na' K' % p K s 33* 1500* Ratio B' 0 -0.10 6.6 � 0.06 � 0.002 ...... · ...... � ...... ····· .. . � ...... � ...... :...... � .. --�-- ······- ...... -�-...... ; ...... ;...... �...... · ...... ··· ···�>- ---:� ...... ··· . ·· ...... L�:; - . -�::; ����:--: �-:::-- . . . . . - ...... L ...... i...... i ...... ;...... i ...... ; ...... L . � . . ; ...... ; ...... ; ...... L ...... � ...... � .... :�::��: :� ·r··�-::H.. ..� .:��- -- 7 . t- � ��-+-..�:�. ., ... ..�-��--- . :->---::-�:--� ...... �;- ��-:...... ;;••• ••::[:;•t�;. • ;JJ;� •L;; r:: •.• ••;I •• :;\):: ;�•• .•:�; :; .. •• ;; t:: :::: . t; :; ...... � . . . ! . ---.. - ...... � ��--� � �:� . �:-�� .....�:��� . �.� ...... �� �� �:��-- �--�� �:� 1 ...... Depth Organic C Total N Extractable P (mg/kg) Extractable K Fe Mn Cu Zn (m) (%) (%) Acid Bicarb. (meq%) DTPA-extractable (mg/kg) s' o-o.1o 5.9 0.33 32 55 1.3 69 104 3.8 4.2 'aqueous cations at pH 7.0 * -33kPa (-0.33bar) and -1500kPa (- 15 bar) using pressure plate apparatus ' refers to the bulking of a number of surface samples prior to analysis 147 Appendix 3 Analytical data for example soil profiles GREYMARE EXAMPLE SOIL PROFILE SOIL GROUP: Greymare SUBSTRATE MATERIAL: Granite SITE NO: Site 7 LOCATION: Greymare School Rd., 900 m south of Highway, road SLOPE: 3% reserve AMG REFERENCE: 378 200 mE, 6 881 500 mN, Z56 LANDFORM ELEMENT TYPE: Hillslope GREAT SOIL GROUP: Solodized solonetz LANDFORM PATTERN TYPE: Rise PRINCIPAL PROFILE FORM: Dy3.43 VEGETATION: AUSTRALIAN SOIL CLASSIFICATION: Eutrophic, Mottled STRUCTURAL FORM: Open forest Subnatric, Grey Sodosol DOMINANT SPECIES: Eucalyptus tereticomis, E. crebra, E. melliodora PROFILE MORPHOLOGY CONDITION OF SURFACE SOIL WHEN DRY: Hard setting HORIZON DEPTH (m) DESCRIPTION A1 0.00 to 0. 10 Very dark greyish brown (lOYR 3/2) coarse sandy clay loam; moderate, 5-10 mm, granular structure; moderately weak consistence; clear change to - A2e 0.10 to 0.30 Pale brown (10YR 6/3) clayey coarse sand; massive; moderately firm consistency; abrupt change to - B21 0.30 to 0.60 Pale yellow (2.5Y 7/3) coarse sandy medium heavy clay, with very few distinct, fine red mottles; strong, >50 mm, columnar structure; moderately strong consistence; gradual change to - B22 0.60 to 0.80 Pale yellow (2.5Y 7/4) coarse sandy medium clay, with common distinctmedium red mottles; weak, 10-20 mm, angular blocky structure; moderately strong consistence; gradual change to - B/C 0.80 to 1.20 Olive yellow (2.5Y 6/6) coarse sandy clay loam, withmany medium red mottles; massive; moderately strong consistence. LABORATORY DATA Depth pH EC Cl Particle Size (%) Exch. Cations (m.eq/100g)' ESP Total Elements (%) Moisture (%) Dispersion (m) (dS/m) (%) cs FS Si c CEC Ca'· Mg'· Na' K' % p K s 33* 1500* Ratio B' 0 · 0.10 7.5 : 0.06 0.002 ...... · · · ...... ; - ..· ·· .. . - -· ...... -··. · .. . ..� -...... · .. .. . · - -. ... · .. .. -�··. ·· - · · . · - - · ...... � : ;� : r �:��� �� r -� r ·�-�� . �:�; : T � �-�� T �� �� T � "T �:� ! ;·_� r�:�; �; �-�;; �-�;� · T ; �:�� . . . . · · ... . . -� . .;...... � .. . ; ...... �-- ...... ·� ...... · �·-· ...... ······ ·· ...... � ...... ;...... �-...... - ---· ...... ·····- ---· ... . . ··· .... -�-...... ·········· .. i . ... ····· ·-·· .. .. . -- · ...... ...... ��-:-�� ...... :. � ... L�-��--L���-�� .. ..�� .. ...�� ...... �.�. ...L.� -�...... � ....L.. �:�. . . . �.-� ... ..�:-�� . ..�:�� -...... � ...... �:�.��-.L�:���.. L�:���- --...... � ...... � :�-� ...... i i \ i L ! ...... �� -:.�-� ...... �-- �---1..�:��--l .. �:�.�� .. ..��---l ... ��---l.... ��-..1.--�� .... ----��---L�:� ...i ...�- �... l ...�:� .. ...�:-� �-.. --��:� .... �:�.�� ..1..�:�� �--L�:���...... �� ...... � ::.� ...... 80 . 90 7.1 0.36 0.049 38 26 15 20 11 5.2 4.2 1.3 0.13 11.8 0.005 1.30 0.004 9 0.75 . .. j . j j j . j j j j Jj . j j lj . ... · ·:· ·; .... . ;_· ·-· - �- . ·· : ·;� .. ...� -·- ··· ; .. · ·· . �.. ..· �· ··· ····� ;···· ·· : ·· · · .. · ·· .. · --- ...;� . -- .. - - : -.. ·· - ...... ;�� ; � � r�� 1 � ; - � r � r � -r ; r � � r ;� r �:� ...r �:�� �:�� r � �� r �-�� 1 ...... Depth Organic C Total N Extractable P (mg/kg) Extractable K Fe Mn Cu Zn (m) (%) (%) Acid Bicarb. (meq%) DTPA-extractable (mg/kg) B1 0-0.10 1.6 0.09 13 18 0.55 10 27 0.25 0.35 'aqueous cations at pH 7.0 * -33kPa (-0.33bar) and -1500kPa (- 15 bar) using pressure plate apparatus ' refers to the bulking of a number of surface samples prior to analysis 148 Appendix 3 Analytical data for example soil profiles HANMER EXAMPLE SOIL PROFILE SOIL GROUP: Hanmer SUBSTRATE MATERIAL: Lateritised sandstone SITE NO: Site 1 LOCATION: Stonehenge Road, Leybum SLOPE: 2% AMG REFERENCE: 353 300 mE, 6 999 200 mN, Z56 LANDFORM ELEMENT TYPE: Hillcrest GREAT SOIL GROUP: Yellow podzolic LANDFORM PATTERN TYPE: Low hills PRINCIPAL PROFILE FORM: Dy3.21 VEGETATION: AUSTRALIAN SOIL CLASSIFICATION: Mottled, Magnesic, Red STRUCTURAL FORM: Open forest Kurosol DOMINANT SPECIES: Eucalyp tus crebra, Acacia leiocalyx, Callitris glaucophylla, Angophora leiocarpa PROFILE MORPHOLOGY CONDITION OF SURFACE SOIL WHEN DRY: Hard setting HORIZON DEPTH (m) DESCRIPTION AI 0.00 to 0.10 Dark brown (7 .5YR 4/2) sandy loam; many coarse fragments; weak, 5-l 0 mm, polyhedral structure; very weak dry consistence; clear change to - A2 0.10 to 0.45 Brown (7.5YR 5/4) sandy loam; abundant gravel; massive; few ferruginous nodules; clear change to B21 0.45 to 0.55 Yellowish red (5YR 5/6) heavy clay, with few, faint pale mottles; few coarse fragments (gravel/quartz/ironstone); weak 10-20 mm, polyhedral structure; very firm dry consistence; gradual change to B22 0.55 to 0.9 Yellowish red (5YR 5/8) medium clay, with many grey mottles; coarse fragments, quartz and ironstone common; weak, 10-20 mm, angular blocky structure; gradual change to - B/C 0.90 + Pale red (2.5YR 711) light clay, with common, prominent red mottles; weak, 10-20 mm, angular blocky structure; sandstone fragments. LABORATORY DATA Depth pH EC Cl Particle Size (%) Exch. Cations (m.eq/1 OOg)' ESP Total Elements (%) Moisture (%) Dispersion (m) (dS/m) (%) cs FS Si c CEC Ca'· Mg'· Na· % p K s 33* 1500 Ratio ······B' ·0-0.10· ······ ···5.6··· 0.03·· ·0.002· ··· ······· ··· · .. ···· ··· · ··· ·············· ·· ······ ·· · ·· · ········· .. · · ·· .. ·· ········· ······· ...... ······· �.�:�� ��� r���--r�.��; �� r �� r � r�; � r��� ·r·; � : ����r ���;· ���;�r���� r ���;� · T � ·· �:;; ...... ·········· :-··········r···········.······· ··:-··········+·········-�·········· ···············�··········�·········· �-········:-··········...... ···········�··········· �--········· ············�··········· ...... �·.�.�. :�.�·�···· ...�:� . . . . � ...... � ..�: .�� .. � ..�:. ���··· ···�·�···�···��...... � ...... �:...... � ...... �: .�� . � ... � ...... �: ��. . ..�:��· ·· ....� . . . ..�: ��.�. . ..�: ��.�...... � ...... �:� �······· 0.45 - 0.55 5.1 0.02 0.002 26 20 t 3 t 52 4 t 0.08 1.5 t 0.17 t 0.09 4 0.020 (.�:0.109�.�� .. ; O.Q15 .; 14 0.30 ····················· ··········:··········�·! ! -·········· ·········r·! ·········�··········T··········! ! ···············.:-··········:-··········! ! !:·········�·········· ! ········· ···········�·! -········· !:- ··········· ············�···········! ···················· ···�·��·�·�·��··· ···:·:······:·:·��·····:·�::·· ···::·······��········�········:�··· ...... � ...... :.� �······:··:··· ···�·�:···�·:�·· ····:··· ..�.:�: ····�·�·�·· ···�·::·:·· ·················:·�···· ·······:·:>···· Depth Organic C Total N Extractable P (mg/kg) Replaceable K Fe Mn Cu Zn (m) (%) (%) Acid Bicarb. (meq%) DTPA·extractable (mg/kg) B' 0 -0.10 3.4 0.16 18 8.0 0.25 44 17 0.11 41 'aqueous cations at pH 7.0 * -33kPa (-0.33bar) and -1500kPa (-15 bar) using pressure plate apparatus ' refers to the bulking of a number of surface samples prior to analysis 149 Appendix3 Analytical data for example soil profiles KARANGI EXAMPLE SOIL PROFILE SOIL GROUP: Karangi SUBSTRATE MATERIAL: Traprock SITE NO: Site 14 LOCATION: Leybum Forestry Rd., Thanes Creek. SLOPE: 2% AMG REFERENCE: 369 400 mE, 6 891 200 mN, Z56 LANDFORM ELEMENT TYPE: Hillslope GREAT SOIL GROUP: Soloth LANDFORM PATTERN TYPE: Low hills PRINCIPAL PROFILE FORM: Dy3.42 VEGETATION: AUSTRALIAN SOIL CLASSIFICATION: Mesotrophic, Subnatric, STRUCTURAL FORM: Woodland Brown Sodosol DOMINANT SPECIES: Eucalyp tus conica, E. microcarpa, E. dealbata PROFILE MORPHOLOGY CONDITION OF SURFACE SOIL WHEN DRY: Hard setting HORIZON DEPTH (m) DESCRIPTION A1 0.00 to 0.20 Brown (lOYR 4/3) clay loam; very abundant large pebbles; gradual change to - A2e 0.20 to 0.35 Yellowish brown (lOYR 5/4 moist, lOYR 7/2 dry) conspicuous bleach, sandy clay loam; very abundant large pebbles; clear change to - B21 0.35 to 0.55 Yellowish brown (lOYR 5/8) medium heavy clay, with faint, fine yellow mottles; very few small pebbles; moderate angular blocky structure; gradual change to - B22 0.55 to 0.70 Brownish yellow (lOYR 6/6) medium clay, with faint, finered mottles; common angular fragments; massive; gradual change to - c 0.70 + Weathered rock. LABORATORY DATA Depth pH EC Cl Particle Size (%) Exch. Cations (m.eq/100g)' ESP Total Elements (%) Moisture (%) Dispersion (m) (dS/m) (%) cs FS Si c CEC Ca'' Mg'' Na' K' % p K s 33* 1500* Ratio ····················· ··········-······················· ...... ··········-·········.. ··········-··········-··········· ...... , ...... 0 - 10 6.0 0.01 0.001 27 42 15 14 4 2.2 1.4 0.05 0.30 0.040 1.20 0.015 5 0.77 ····················· ··········�� ··········� ············ ·········� ·-·········r� ··········+� ·········· ··········!"� ··········r� ··········r� ··········� ·-·········· ·········· ············+� ············:-� ············ ············� ············ ····················· 20 -30 6.0 i 0.03 : 0.001 21 : 34 i 2 : 41 5 : 0.70 : 2.9 : 0.31 : 0.15 8 0.019 : 1.19 : 0.009 : 6 0.87 ...... :...... : ...... :...... :...... :...... :...... : ...... :...... :...... :...... :...... :...... , ...... � .: .�.�······ ... ..� ... ..�:.�� ..l..���.�� ...... l ...... t ...... l ...... �� ... L�:��...... : .. : ... l ...�:� .. .l ...�:.�:...... �.: ...... l ...... l ...... ) ...... � � i ! ...... � .�. :��···· .. . .. �·.� ... l ..�:.� � . .) .. ���.:�.. . ..�� ... t ... �� ... L ...� � ... l .. . ��...... � � .. .l..�:�� .. .. � .::�.. t ...::� ...t ...�: .�� ...... �. �... ..���.:.� .. l ...� :�� .. [ ..�:��·�· ·· ...... l... ..� �...... ���.� ...... 80 -90 7.4 [ 0.60 [ 0.077 28 [ 32 [ 2 [ 38 15 [ 0.18 [l 8.3 [ 6.2 [ 0.08 42 0.012 [ 2.43 [ 0.008 [ 8 0.77 Depth Organic C Total N Extractable P (mg/kg) Extractable K Fe Mn Cu Zn (m) (%) (%) Acid Bicarb. (meq%) DTPA-extractable (mg/kg) B' 0-0.10 2.1 0.11 <5 0.35 'aqueous cations at pH 7.0 * -33kPa (-0.33bar) and -1500kPa (- 15 bar) using pressure plate apparatus ' refers to the bulking of a number of surface samples prior to analysis 150 Appendix 3 Analytical data for example soil profiles LEYBURN EXAMPLE SOIL PROFILE SOIL GROUP: Leybum SUBSTRATE MATERIAL: Quaternary alluvium SITE NO: Site 12 LOCATION: Karara- Leybum Rd. SLOPE: <0.5% mE mN AMG REFERENCE: 359 500 , 6 982 600 , Z56 LANDFORM ELEMENT TYPE: Plain GREAT SOIL GROUP: Soloth LANDFORM PATTERN TYPE: Gently undulating rises PRINCIPAL PROFILE FORM: Dy2.42 VEGETATION: AUSTRALIAN SOIL CLASSIFICATION: Eutrophic, Subnatric, Brown STRUCTURAL FORM: Woodland Sodosol DOMINANT SPECIES: Eucalyptus mel/iodora, E. tereticomis, E. microcarpa, Cassinia /aevis PROFILE MORPHOLOGY CONDITION OF SURFACE SOIL WHEN DRY: Hard setting HORIZON DEPTH (m) DESCRIPTION Al 0.00 to 0.05 Dark yellowish brown (lOYR 4/4) fine sandy clay loam; weak, 5-10 mm, granular structure; firm dry consistence; clear change to - A2e 0.05 to 0.20 Brown (lOYR 5/3 moist, lOYR 8/2 dry) conspicuous bleach, clay loam; massive; very firmdry consistence; abrupt change to - B21 0.20 to 0.60 Yellowish brown (lOYR 5/4) medium clay; weak, 20-50 mm, angular blocky; rough faced peds; few roots; strong dry consistence; gradual change to - B22 0.60 to 1.10 Yellowish brown (lOYR 5/4) medium clay; massive; no roots; strong dry consistence. LABORATORY DATA Depth pH EC Cl Particle Size (%) Exch. Cations (m.eq/100g)' ESP Total Elements (%) Moisture (%) Dispersion (m) (dS/m) (%) cs FS Si c CEC Ca'· Mg'· Na' K' % p K s 33* 1500* Ratio ' B 0 ·10 6.0 ! 0.03 ! 0.007 ...... ;...... :...... :...... :...... :...... :...... : ...... :...... �.:.�� ...... :�� . . �--�� . �����...... ; . ...:�� . :. : .. �---��--- --���.:� ..... ····················...... ��� -� ...... l .. . t .. .. �. .. t...��... t . �� t...��--- . .: ..... i . .�- -�...t . .r..�:��---i.. . �·.:� ...... �--��� ...... t .....� 20 -30 6.1 : 0.07 : 0.004 4 : 37 : 34 : 28 8 : 3.0 : 3.8 : 0.60 : 0.47 7.5 0.013 !: 1.79 0.011 : 8 0.77...... · · ; - ···· · ��-�-�� . · ··�-��·· �-�� ·· ···· ·� · ·�� · · ��- ·� · �· · ···� � · ··� �·· · �--�-� ;;···· ··� -���·· ···; ·�··· � �-��-· ;; �:�� -��� ; ; ; ; ; : : - .- : ...... � � · � � � � � � ; ...... ; ...... � ...... ;��- :-�� ...... :--·······-t ·-········· ········-t·-·······- (·-·······-t·-········ ·········-t·-·······-t··········t·-········t t ···········-:·-·········· ...... � .. � - ...... L..�� . . �...... · ..� -:� ...... �- -��� ...... � -�� ... ..� ��-�� ...... �:�.� ...... � - · · . l...��...... �� ...... · - - � . :: : �:+: ::: � : : : � :. ;:: ...... : :.� : <�+ : :: : :. Depth Organic C Total N Extractable P (mg/kg) Extractable K Fe Mn Cu Zn (m) (%) (%) Acid Bicarb. (meq%) DTPA·extractable (mg/kg) s' o-o.1o 1.4 0.07 6.0 14 0.63 61 69 0.50 4.8 'aqueous cations at pH 7.0 * -33kPa (-0.33bar) and -1500kPa (- 15 bar) using pressure plate apparatus ' refers to the bulking of a number of surface samples prior to analysis 151 Appendix3 Analytical data for example soil profiles LYRA EXAMPLE SOIL PROFILE SOIL GROUP: Lyra SUBSTRATE MATERIAL: Granite SITE NO: Site 2 LOCATION: Near Saxby Rd., New England Highway, Lyra SLOPE: 0-1% AMG REFERENCE: 387 000 mE, 6 809 400 rnN,Z56 LANDFORM ELEMENT TYPE: Plain GREAT SOIL GROUP: Sol odic LANDFORM PATTERN TYPE: Plain PRINCIPAL PROFILE FORM: Dy 2.53 VEGETATION: AUSTRALIAN SOIL CLASSIFlCATION: Magnesic, Mesonatric, Grey STRUCTURAL FORM: Woodland Sodosol DOMINANT SPECIES: Eucalyp tus tereticomis, E. microcarpa, Angophora floribunda PROFILE MORPHOLOGY CONDITION OF SURFACE SOIL WHEN DRY: Hard setting HORIZON DEPTH (m) DESCRIPTION A1 0.00 to 0.10 Greyish brown (lOYR 5/2) clay loam; massive; weak dry consistence; clear change to - A2e 0.10 to 0.25 Light brownish grey (lOYR 6/2 moist, 10YR 7/2 dry) conspicuous bleach, clay loam; massive; weak dry consistence; abrupt change to - B21 0.25 to 0.60 Light yellowish brown (2.5Y 6/3) medium heavy clay; weak, 10-20 mm, angular blocky; strong dry consistence; clear change to - B22 0.60 to 0.80 Light olive brown (2.5Y 5/4) coarse sandy light clay; massive; strong dry consistence; gradual change to B23 0.80 to 1.00 Light yellowish brown (2.5Y 6/4) coarse sandy light medium clay, with faint, fine greyish red mottles; massive; very firm dry consistence. LABORATORY DATA Depth pH EC Cl Particle Size (%) Exch. Cations (m.eq/1 DOg)' ESP Total Elements (%) Moisture (%) Dispersion (m) (dS/m) (%) cs FS Si c CEC Ca'· Mg'· Na· K' % p K s 33* 1500* Ratio s'o -o.1o 6.6 : 0.03 : 0.002 ····················· ··········t ··········� ············ ········-�·-········ t ·······--·-r ·········· ··········t ·········-�---·-·····r ·········-� ·-·········· ·········· ············t ············r············ ...... 1 ············ ····················· 0.00·0.10 6.3 : 0.03 : 0.001 11 : 35 : 45 : 11 11 : 3.1 : 1.3 : 0.10 : 0.21 <1 0.019 : 1.79 : 0.025 : 5 0.81 ...... ··········�---·······: ············ ········-�---······· � -·········�·········· ··········� ··········:··········:·······--·�············ ...... --·········-�····· .. ··· ..: ·------···· .. --··········� ············ ···················· 0.25·0.35 6.6 0.23 0.021 13 27 ! 39 23 10 0.33 5.9 2.1 0.08 21 0.008 1.74 0.011 9 0.92 ...... ! ...... ! ...... ! ...... ! ...... ! ...... ! . .. . ! ...... ! ...... ! ! ! ...... :. . . : ...... :.. .:. .. . . :...... :. .. . : ...... :.. :...... :...... :...... ; ...... :.���� - �···· --·::-�··· --�:�·· --�-�:> ·-�� ·-· ---�� ··· <: ··· ···::-·· ----��-·· --�-:�-· ···�:··· --:-:-·· ···�-·��··· ··�-��:·- ···�-�� -· ..� - ��:-·· ...... ·······� -:-�···--··· ···· : · · · · • · · · · --;:��-· • , ...... ��---- Depth Organic C Total N Extractable P (mg/kg) Extractable K Fe Mn Cu Zn (m) (%) (%) Acid Bicarb. (meq%) DTPA-extractable (mg/kg) s' o -o.1o 2.1 0.13 22 11 0.21 84 13 0.14 24 'alcoholic cations at pH 8.5 * -33kPa (-0.33bar) and -1500kPa (- 15 bar) using pressure plate apparatus ' refers to the bulking of a number of surface samples prior to analysis 152 Appendix 3 Analytical data for example soil profiles MAROON EXAMPLE SOIL PROFILE SOIL GROUP: Mardon SUBSTRATE MATERIAL: Sandstone SITE NO: Site 5 LOCATION: Glen Rd., Warwick SLOPE: 2-3% AMG REFERENCE: 403 300 mE, 6 879 500 mN, Z56 LANDFORM ELEMENT TYPE: Hillcrest GREAT SOIL GROUP: Red Earth LANDFORM PATTERN TYPE: Low hills PRINCIPAL PROFILE FORM : Gn2.12 VEGETATION: AUSTRALIAN SOIL CLASSIFICATION: Haplic, Eutrophic, Red STRUCTURAL FORM: Cleared Kandosol DOMINANT SPECIES: Acacia spp. PROFILE MORPHOLOGY CONDITION OF SURFACE SOIL WHEN DRY: Loose HORIZON DEPTH (m) DESCRIPTION Al 0.00 to 0.10 Dark brown (lOYR 3/4) coarse sandy loam; few rounded quartz and sandstone medium pebbles; moderate, 5- 10 mm, granular structure; very weak consistence; clear change to - B21 0.10 to 0.30 Dark reddish brown (5YR 3/4) coarse sandy clay loam; many large rounded quartz pebbles and subangular sandstone; massive; very weak consistence; gradual change to - B22 0.30 to 0.60 Yellowish red (5YR 4/6) coarse sandy light clay; abundant large quartz and sandstone pebbles; massive; moderately weak consistence; gradual change to - B23 0.60 to 0.90 Yellowish red (5YR 5/6) coarse sandy light clay; abundant cobbles of quartz and sandstone; massive; moderately weak consistence. LABORATORY DATA Depth pH EC Cl Particle Size (%) Exch. Cations (m.eq/1 DOg)' ESP Total Elements (%) Moisture (%) Dispersion (m) (dS/m) (%) cs FS Si c CEC Ca'' Mg'' Na' K' % p K s 33* 1500* Ratio s' o -o.1o 5. 7 : 0.04 ! 0.002 ...... ··········: ·········-� ·-·········· ·········: ··········+ ··········-:-·········· ··········: ··········!' ··········:-··········: ············ ...... ············:············:············ ············:- ············ ···················· ...... �.- ..:� ... l ..�:�� .. l ..� :���··· ...�� .. .L..��... L...�..... l ...� .�···· . ...� ... . L.�:.� .. .L..::� ...l ..�:�� . .. \ ...� . .�� ··· ...�: ...... �:.��� . ..\ ..� .��� . . \ .. ���.�� ...... [ .....� ...... �.�.: ...... 20 -30...... �:�6.5 ! 0.04 ! 0.002 46 ! 28 ! 9 ! 17 5 ! 2.1 ! 1.4 ! 0.04 : 1.0 <1 0.072 ! 0.612 ! 0.016 : 5 0.57 ...... �-...... ;...... ;...... -�· ...... ·--�···· ...... ···�·-· ...... ;...... :...... �...... ········· ...... : ...... :...... ;...... 1 ...... ��.-..�� ······ ...... l..�... �� .. ..�: .���·-· .. .�.� ... l ... �� ...... �.� ... L....:...... � ..� ... l ...::� .. L�:��. . ... �. .� .�··· ...... �. .��� .. ..�·.�.�� .. . . �:�.�.� ...... �...... �:� .�······· 80 -90 7.1�:� : 0.04 i: 0.002 52 : 21 l: 10 : 17 ...... �3 .l: 1.6 : 1.3 : 0.13 :l 0.35 4 0.064 :: 0.518 :[ 0.009 :[ 6 0.68 Depth Organic C Totai N Extractable P (mg/kg) Extractable K Fe Mn Cu Zn (m) (%) (%) Acid Bicarb. (meq%) DTPA-extractable (mg/kg) B' 0 -0.10 2.9 0.23 18 41 0.41 62 83 0.58 5.3 • aqueous cations at pH 7.0 • -33kPa (-0.33bar) and -1500kPa (-15 bar) using pressure plate apparatus ' refers to the bulking of a number of surface samples prior to analysis 153 App endix 3 Analytical data for example soil profiles MAXLAND EXAMPLE SOIL PROFILE SOIL GROUP: Maxland SUBSTRATE MATERIAL: Sandstone SITE NO: Site 8 LOCATION: 2.9 km south of Donovan Rd., T'wba-Karara Rd. SLOPE: 2% AMG REFERENCE: 359 100 mE, 6 893 100 mN, Z56 LANDFORM ELEMENT TYPE: Plain GREAT SOIL GROUP: Solodized solonetz LANDFORM PATTERN TYPE: Plain PRINCIPAL PROFILE FORM: Dy 2.43 VEGETATION: AUSTRALIAN SOIL CLASSIFICATION: Eutrophic, Mesonatric, Grey STRUCTURAL FORM: Open forest Sodosol DOMINANT SPECIES: Allocasuarina luehmannii, Eucalyptus populnea, Cassinia spp. PROFILE MORPHOLOGY CONDITION OF SURFACE SOIL WHEN DRY: Hard setting HORIZON DEPTH (m) DESCRIPTION AI 0.00 to 0.15 Brown (IOYR 4/3) loamy sand; massive; very weak consistence; clear change to - A2e 0. 15 to 0.30 Pinkish white (7.5YR 8/2 dry) conspicuous bleach, loamy sand; massive; moderately weak consistence; abrupt change to - B21 0.30 to 0.80 Greyish brown (lOYR 5/2) sandy medium clay, with fe w, fine distinct orange mottles; strong, >50 rnrn, columnar structure; moderately strong consistence; gradual change to - BIC 0.80 to 1.30 Yellowish brown (lOYR 5/6) coarse sandy light clay, with few, fine distinct orange and grey mottles; very finn consistence. LABORATORY DATA Depth pH EC Cl Particle Size (%) Exch. Cations (m.eq/100g)' ESP Total Elements (%) Moisture (%) Dispersion (m) (dS/m) (%) cs FS Si c CEC Ca'· Mg'· Na' K' % p K s 33' 1500' Ratio s' o -o.1o 6.5 : 0.03 : 0.004 ·------�·:·;·�------· --·�·;---�--�-�;·T·�����-- --�;-·-.: ··-�;--··r. ····�·--r . --;·------�----:. --·;:�···.i ···;··;···.: ---�-�---.r ·--�:��--- ·-��;-- --���;�--r. �:���·r . ··�-���------T. ·---�------���;------· ...... � ...... ; ...... ········-�---········�---·······�·-········ ...... � ...... ; ...... �·-·······-�·-·········· ...... ···········-�·-·········-�·-·········· ···········-�·-·········· ...... 20 · 30 6.5 i 0.01 i 0.002 55 i 36 : 6 : 3 2 : 0.12 : 0.21 i BD i 0.08 «1 0.005 i 0.148 i 0.006 : 0.97 ••••••••••••••••••••• •••••••••• � •••••••••• � • ••••••••••• •••••••••� ••••••••••.� •••••••••• :. •••••••••• ••••••••••;. •••••••••• � ••••••••••!, •••••••••• � •••••••••••• •••••••• ., ...... :...... :.•••••••••••• •••••••••••• !...... ------��-:-�-�------� 1. �:. �:�.: .. ---��---l---��---l----�----1---�:...... :� :� - �� l : __�: ��---..:�:� .. --�:�-��--1--�:��--.l--�:��:...... ) .....:�---- -�:�� · ---�----- . :�--l-- � ---L� --�------��_J ------;·:�-:-�:�------·:-:------:-��-----�-:::-- --::···----�:-·-·····;------��------::------:-�--·-···::-:------:->----:·:�--· ---:-:--- --�-:��-----:-��:---·:-:�:-· ...... :: ...... ::.�-----···· Depth Organic C Total N Extractable P (mg/kg) Extractable K Fe Mn Cu Zn (m) (%) (%) Acid Bicarb. (meq%) DTPA-extractable (mg/kg) B1 0 -0.10 0.79 0.05 13 14 0.18 36 15 0.09 0.42 'alcoholic cations at pH 8.5 BD below the limit of detection * -33kPa (-0.33bar) and -1500kPa (-15 bar) using pressure plate apparatus 1 refers to the bulking of a number of surface samples prior to analysis 154 Appendix3 Analytical data fo r example soil profiles POZIERES EXAMPLE SOIL PROFILE SOIL GROUP: Pozieres SUBSTRATE MATERIAL: Granite SITE NO: Site 4 LOCATION: Road cutting, Spring Creek Rd., Arniens SLOPE: 3% AMG REFERENCE: 385 200 mE, 6 834 500 mN, Z56 LANDFORM ELEMENT TYPE: Hillslope GREAT SOIL GROUP: Siliceous sand LANDFORM PATTERN TYPE: Rise PRINCIPALPROFILE FORM : Uc2.23 VEGETATION: AUSTRALIAN SOIL CLASSIFICATION: Basic, Regolithic, Bleached- STRUCTURAL FORM: Open forest Leptic Tenosol DOMINANT SPECIES: Angophorafloribunda, A. subvelulina, Banksia spp. PROFILE MORPHOLOGY CONDITION OF SURFACE SOIL WHEN DRY: Firm HORIZON DEPTH (m) DESCRIPTION All 0.00 to 0.10 Dark greyish brown (lOYR 4/2) coarse sandy loam; weak, 10-20 mm,granular structure; moderately weak consistence; clear change to - A12 0.10 to 0.20 Pale brown (lOYR 6/3) coarse sandy loam; massive; moderately weak consistence; gradual change to - A21 0.20 to 0.60 Light grey (lOYR 7/2) loamy coarse sand; massive; moderately weak consistence; gradual change to - A22 0.60 to 0.80 Light grey (lOYR 7/2) loamy coarse sand, with very few, medium, distinct yellow mottles; massive; very firm consistence; gradual change to - A3 0.80 to 0.90 Light grey (10YR 7/2) clayey coarse sand, with very few, medium, distinct yellow mottles; very finn. LABORATORY DATA Depth pH EC Cl Particle Size (%) Exch. Cations (m.eq/100g)' ESP Total Elements (%) Moisture (%) Dispersion (m) (dS/m) (%) cs FS Si c CEC Ca" Mg'· Na· K. % p K s 33* 1500* Ratio B' 0 -0.10 4.6 : 0.08 : 0.004 ... ••• •••••••• ••...... •••••• �--········ •.....•••. ••• ·····-�--••.•.•.• .i- ...... ••• ... ······�- ...... �--····· .. -�·-····· . j...... i ...... �-- f...... i ...... --�...... · ··· ••. :.:0•1�� :[ ;;.ri:L: ••• · j :;t I•••::: · :�:�:�J:�: J · ::: ••• ' ; • - •••• : •• •••r : � ::: • -·---;';------·-· --:-�:� . . ------·-- --- . ---· . ;�-�-�-.L.�:��-L�:�: .. �--�-�--- . . . . �--�: ... .. ���-:�-- ...... ·------···· �� �� .. . �:-��--1--�--���--- �� �� .. ... � ...... --�---��:...... �------��� 80 .90 5.6 �l 0.01 � 0.002 53 l: 28 L: �:.16 L: 4 ...... :t 0.29 : 0.72 : 0.02 ..t: 0.05 2 0.012 :[ 4.15 :[ 0.008 :l 2 0.79 Depth Organic C Total N Extractable P (mg/kg) Extractable K Fe Mn Cu Zn (m) (%) (%) Acid Bicarb. (meq%) DTPA-extractable (mg/kg) B1 o-0.10 2.2 0.10 13 31 0.27 79 22 1.3 10 'aqueous cations at pH 7.0 * -33kPa (-0.33bar) and -1500kPa (- 15 bar) using pressure plate apparatus ' refers to the bulking of a number of surface samples prior to analysis 155 Appendix 3 Analytical data fo r example soil profiles PRATTEN EXAMPLE SOIL PROFILE SOIL GROUP: Pratten SUBSTRATE MATERIAL: Alluvium SITE NO: Site 3 LOCATION: Blacksoil Lane, Wheatvale SLOPE: <1% AMG REFERENCE: 388 500 mE, 6 885 700 mN, Z56 LANDFORM ELEMENT TYPE: Plain GREAT SOIL GROUP: Black earth LANDFORM PATTERN TYPE: Alluvial plain PRINCIPAL PROFILE FORM: Ug5. 16 VEGETATION: AUSTRALIAN SOILCLASSIFICATI ON: Epicalcareous STRUCTURAL FORM: Cleared - cropping Epihypersodic, Self-mulching, Black Vertosol DOMINANT SPECIES: E. tereticornis PROFILE MORPHOLOGY CONDITION OF SURFACE SOIL WHEN DRY: Self-mulching HORIZON DEPTH (m) DESCRIPTION A1 0.00 to 0.15 Very dark brown (10YR 2/2) heavy clay; strong, 20-30 mm, angular blocky; smooth ped; very strong dry consistence; clear change to - B21 0. 15 to 0.30 Very dark greyish brown (10YR 311) heavy clay; strong, 20-50 mm, angular blocky structure; few calcareous nodules, few calcareous soft segregations; clear change to - B22 0.30 to 0.80 Very dark greyish brown (lOYR 3/2) heavy clay; strong, 20-50 mm, lenticular structure; very strong dry consistence; common calcareous nodules, few calcareous soft segregations; clear change to - B23 0.80 to 1.40 Dark greyish brown (10YR 4/2) heavy clay; strong, 50-100 mm, lenticular, parting to 20-50 mm, angular blocky; very strong dry consistence; common calcareous nodules, few calcareous soft segregations. LABORATORY DATA Depth pH EC Cl Particle Size (%) Exch. Cations (m.eq/1 OOg)' ESP Total Elements (%) Moisture (%) Dispersion (m) (dS/m) (%) cs FS Si c CEC Ca'· Mg'· Na" K" % p K s 33* 1500* Ratio B' 0 -0.10 8.0 : 0.08 : 0.001 ...... �-····. ····�···...... �-· ...... ··:· ...... �-...... ··········� · ...... ·: ...... ··:··· ...... ·: ...... -:- ...... ·:· ...... �...... 1 ...... - - ---···· ·--�--�---L�.. :� .. l .. ���-��-- ...... •. ..�� ... l ... ---· ...... ��----l---��--.L.�:� ..�:��-- ... . --���-��--l ..�:� ��--L�:-���-- .. . ---· ····--- - ...... �:�� . .: .... l � -l. �� .. �:. L ...l �:� ...... ] . �� ���: 20 - 30 8.7 : 0.30 : 0.023 1 : 10 : 26 : 66 62 : 22 : 33 : 7.5 : 0.45 12.1 0.119 : 0.790 : 0.026 : 33 0.63 ...... ··········-r·· ...... � ...... � ...... � -····· ... -� ...... -� ...... ····: ...... ----� ...... -�········...... ·+ ········· .. . � ...... �...... ···------··· ---�--�---1 ..�:- ��--l--���-�:...... � ...... ��---L��------��... ..�-� ----l---��----l ...�-�---L� :��-- ·------·· . �:�-�-�--L�::.��--.L-�:��-�-- ...... � ---· ...... ---····· ��:�� .L... � ... l . . 1 . �� . ..1 � �::� 80 -90 8.9 : 1.2 i 0.170 2 : 11 i 23 : 65 59 i 12 : 37 : 13 i 0.43 22 0.123 : 0.803 : 0.015 : 32 0.77 ...... � ····--····!--·--···------·······� ---········�··--··--··+ ··--······ ···--···--� ·------.. :·--·----··:--··· .. ···--� ------·--· ...... ··········--+ --··----....;- ...... -:: ·····--···-- ...... �-:-:� -- ······--�� --- ·---��---·---�:---· ·--:� --- :z�- ---· ·--� -�---·---;- �------�- �--- ·--�� ------:-�---···-�-:� -- ·---::---· --�-:-:� --·--�-�::-- ..� --:�� -- ············ ··--�� ---· ····---� -:-:---····· .... : · · · · · : ;:: : -< , Depth Organic C Total N Extractable P (mg/kg) Extractable K Fe Mn Cu Zn (m) (%) (%) Acid Bicarb. (meq%) DTPA-extractable (mg/kg) s' o -o.1o 1.3 0.09 59 52 0.57 19 10 1.5 0.62 'alcoholic cations at pH 8.5 * -33kPa (-0.33bar) and -1500kPa (-15 bar) using pressure plate apparatus ' refers to the bulking of a number of surface samples prior to analysis 156 Appendix 3 Analytical data for example soil profiles RODGER EXAMPLE SOIL PROFILE SOIL GROUP: Rodger SUBSTRATE MATERIAL: Alluvium SITE NO: Site 6 LOCATION: Rodgers Creek Rd. SLOPE: <0.5% A!\1G REFERENCE: 383 800 mE, 6 881 300 mN, Z56 LANDFORM ELEMENT TYPE: Plain GREAT SOIL GROUP: Solodic LANDFORM PA TIERN TYPE: Alluvial plain PRINCIPAL PROFILE FORM: Dd1.33 VEGETATION: AUSTRALIAN SOIL CLASSIFICATION: Haplic, Hypercalcic, STRUCTURAL FORM: Open woodland Black Chromosol DOMINANTSPECIES: Eucalyp tus populnea, Angophora floribunda PROFILE MORPHOLOGY CONDITION OF SURFACE SOIL WHEN DRY: Hard setting HORIZON DEPTH (m) DESCRIPTION AI 0.00 to 0.10 Very dark greyish brown (lOYR 3/2) clay loam; weak, 2-5 rnm, granular structure; firm dry consistence; clear change to - A2j 0.10 to 0.30 Dark greyish brown (lOYR 4/2 moist), light grey (lOYR 7/2 dry) sporadic bleach, clay loam; massive; strong dry consistence; clear change to - B21 0.30 to 0.65 Very dark grey (lOYR 3/1) medium heavy clay; strong, 20-50 rnm, angular blocky structure; strong dry consistence; gradual change to - B22 0.65 to 0.90 Very dark greyish brown (2.5Y 3/2) medium heavy clay; strong, 20-50 rnm, angular blocky structure; strong dry consistence; gradual change to - B23 0.90 to 1.10 Dark greyish brown (2.5Y 4/2) medium heavy clay; moderate, 10-20 rnm, angular blocky structure; strong dry consistence; many calcareous soft segregations; clear change to - B24 1.10 to 1.50 Brown (1 OYR 5/3) medium clay; massive; strong dry consistence. LABORATORY DATA Depth pH EC Cl Particle Size (%) Exch. Cations (m.eq/1 OOg)' ESP Total Elements (%) Moisture (%) Dispersion (m) (dS/m) (%) cs FS Si c CEC Ca'· Mg'• Na· K' % p K s 33* 1500* Ratio ' B 0 ·0.10 6.8 i 0.10 i 0.004 ····················· ·········· � --········t ············ ·········�·········-� ·-········t ·········· ··········� ··········t ··········r ··········� ·········· ············ ············:············! ············ ············t ············ ···················· 0 · 10 7.1 ! 0.07 ! 0.002 2 ! 36 ! 41 ! 23 18 ! 11 ! 3.1 ! 0.02 ! 1.3 <1 0.055 ! 2.00 ! 0.038 ! 11 0.53 ...... ······· ·········· ...... · .. ········ --······· · ...... ········ ...... ··· ...... : ...... �-...... : ...... f -=- : � + ...... ·:.. . : :...... -� ...... .....�� . . ······ . .�:�� . .. ··· ···· ···· ··· ···· ··· ...... ::� . . �:�.� ..� ...... �:�.:�... ············ ···· · ····· . ..�� . . . . � �:��� � � �� � ��.... � . . �: . .�:: . . . .. �� . .::�. .. ..� .. ��� . . � .�� ... .. � �� ...... �·.:.� ...... 50 . 60 �: 7.3.1 .... � ! 0.04 ! 0.002 2 ! 28 ! 30 ! 42...... 25� \ ! 17 � ! 4.9 �! 0.60... !\ 0.45 2.4 0.023 \ ! 2.00 \ ! 0.012 ! 15 0.63 ...... ····· ..... -···· ..... · ...... ········ ·-·· ...... ·-· - ...... ··· ······· ·...... ··· ...... ·· ...... ············ - ...... � -=- ; � ..... -�.. . � ; + ? : : � ...... .� � ······ ... .. l .� ... �� � ���··· ····�····�···�� .. �� ...... l .. . l .� .. ��...... � .. �:� . . . . �� . . . .. �:�.�� .. ············� ····�·�····· .... . �::.�...... ��--. �:� . . ..t ...... t . . t .. �:...... �.� ....\ �� . .�:� .. . \ .. �.�.� ...... �:� . ... \ � . \ . . ::�·:·:�� ···· ···�· �······:· ·:�·····:.��:··· ...... ·· ·· . . . ························· ···················· ···· : . . .. �:...... �� . .... ��···· ...... �:� ...... �: �� .....� ...... �:� ...... � � � ���� . . �:�.�� .. . � ...... �� . ..:� �.� . . : 1 : . Depth Organic C Totai N Extractable P (mg/kg) Extractable K =:e Mn Cu Zn (m) (%) (%) Acid Bicarb. (meq%) DTPA-extractable (mg/kg) B' 0 ·0.10 2.7 0.21 45 39 1.5 45 30 0.88 2.4 'alcoholic cations at pH 8.5 * -33kPa (-0.33bar) and -1500kPa (- 15 bar) using pressure plate apparatus ' refers to the bulking of a number of surface samples prior to analysis 157 Annonni..- � A nnltJtiF•nl Jntn fn r oYnJnnlo �nil nrn-filoc< 158 GLOSSARY A horizon See Soil horizon. A2 horizon See Subsuiface soil; Bleach. Acid soil A soil giving an acid reaction throughout most or all of the soil profile (precisely, below a pH of 7.0; practically, below a pH of 6.5). Generally speaking, when the pH drops below 5.5 the following specificproblems may occur - aluminium toxicity, manganese toxicity, calcium deficiency and/or molybdenum deficiency. Such problems adversely affect plant growth and root nodulation, which may result in a decline in plant cover and increase in erosion hazard. See pH. Adamellite A variety of granite containing a calcium-bearing plagioclase, and a potassium feldspar, in roughly equal amounts. Aeolian A process whereby soil forming material is transported and deposited by wind. Alkaline soil A soil giving an alkaline reaction throughout most or all of the soil profile (precisely, above a pH of 7.0; practically, above a pH of 8.0). Many alkaline soils have a high pH indicated by thepresence of calcium carbonate, and are suitable for agriculture. However, others are problem soils because of salinity and/or sodicity. Soils with a pH above 9.5 are generally unsuitable for agriculture. See pH. Alluvial plain A plain formed by the accumulation of alluvium on a floodplain over a considerable period of time; this accumulation may be still occurring at present (recent alluvium) or may have ceased (relict alluvium). Alluvium (pl. alluvia) Deposits of gravel, sand, silt, clay or other debris, moved by streams from higher to lower ground. Aquifer A body of permeable rock, for example, unconsolidated gravel or sand, that is capable of storing significant quantities of water, is underlain by impermeable material, and through which groundwater moves. 159 Glossary Arenic Soils in which at least the upper 0.5 m of the profile is non gravelly and of sandy texture throughout. It is also loosely or weakly coherent (see Consistence), and may have aeolian (wind-blown) cross-bedding. This term is used in the Australian Soil Classification (Isbell 1996) to describe Tenosols (see Tenosol). Aureole A zone surrounding an igneous intrusion in which contact metamorphism of the country rock has taken place. B horizon See Soil horizon. Backplain Large alluvial flatoccurring some distance from the stream channel; often characterised by a high watertable and the presence of swamps or lakes. Base status This refers to the sum of exchangeable basic cations (Ca, Mg, 1 K and Na) expressed in cmol ( +) kg- clay. It is used as an indicator of soil fertility and is calculated by multiplying the sum of the reported basic cations by 100 and dividing by the clay percentage of the sample. Three classes are defined: Dystrophic - the sum is less than 5; Mesotrophic - the sum is between 5 and 15 inclusive; and Eutrophic - the sum is greater than 15. It is used for some Great Group or Subgroup distinctions within the Australian Soil Classification (Isbell 1996). Basic A term used in the Australian Soil Classification (Isbell 1996) to describe a soil containing a layer (usually the B horizon) that is not strongly acid and not calcareous. Bleach Subsurface soil (A2 horizon) that is white, near white or much paler than adj acent soil layers. It occurs in varying proportions: conspicuous bleach - 80% or more of the layer is white or almost so, when the soil is dry. sporadic or partial the bleaching occurs irregularly bleach - through the subsurface layer, or as blotches or, as nests of bleached grains of soil material often at the interface of the surface and subsoil layers. 160 Glossary Bleached-Leptic Soils with a conspicuously bleached A2 horizon which directly overlies a hard, continuous, discontinuous or broken layer of calcrete which may be massive, concretionary or nodular� or hard unweathered rock or other hard materials� or partially weathered or decomposed rock or saprolite� or unconsolidated mineral materials. The term is used as a definition for a Tenosol Suborder in the Australian Soil Classification (Isbell 1996). C horizon Layer(s) below the B horizon which may be weathered parent material, not bedrock, little affected by soil-forming processes. Calcic These soils have a layer containing 2-20% soft carbonate and <20% hard carbonate. This term is used to describe a number of Soil Orders in the Australian Soil Classification (Isbell 1996). Calcrete A layer of cemented carbonate accumulation. The material must be hard. CE C (Cation Exchange Capacity) The measure of the capacity of a soil to hold the major cations: calcium, magnesium, sodium and potassium (including hydrogen, aluminium and manganese in acid soils). It is a measure of the potential nutrient reserve in the soil and is therefore an indicator of inherent soil fertility. An imbalance in the ratio of cations can result in soil structural problems. High levels of individual cations (e.g. aluminium and manganese) can also be toxic to plants. Chlorotic An abnormal yellow colour of a plant. Chromosol A Soil Order of theAustralian Soil Classification (Isbell 1996). Soils have a clear or abrupt textural B horizon where the pH is 5.5 (water) or greater in the upper 0.2 m of the B2 horizon. Clays Soils with a uniform clay texture throughout the surface soil and subsoil. -cracking Clay soils that develop vertical cracks when dry. - non-cracking Clay soils that do not develop vertical cracks when dry. 161 Glossary Colluvium (p l. colluvia) Slope deposits of soil and rock material. Colour See Soil colour. Compaction The process whereby soil density is increased as a result of tillage, stock trampling and/or vehicular trafficking. Compaction can lead to lower soil permeability, poor soil aeration resulting in increased erosion hazard and poorer plant productivity. Deep ripping and conservation tillage can alleviate the condition. Concretion See Segregation. (in soil) Consistence (of soil) Refers to the degree of resistance to breaking or deformation when a force is applied. Cracking clays See Clays, cracking. Deep weathering The process by which earthy or rocky materials are slowly broken down into finer particles and soil by chemical processes over a long period of time. The chemical alteration of the rocks involved: • leaching of the calcium-rich cement which previously bound the constituent particles together to form the rocks; • a progressive transformation of feldspar minerals, clay minerals and labile fragments to form a new matrix of kaolinite white clay; • the alteration of iron-rich minerals to form iron oxides (red colour); and • mobilising and recrystallising of silica produced from the breakdown of minerals; more resistant quartz grains were relatively unaffected. See Laterite. Dispersion The process whereby soils break down and separate into their constituent particles (clay, silt, sand) in water. Dispersible soils tend to be highly erodible and present problems for earth works. Dispersion is associated with sodicity levels. See Sodicity. Dissection The process of streams or erosion cutting the land into hill, ridges and flat areas. 162 Glossary ·Drainage The rate of downward movement of water through the soil, (soil profile) governedby both soil and site characteristics. Categories are as follows: • Very poorly drained: free water remains at or near the surface for most of the year. • Poorly drained: all soil horizons remain wet for several months each year. • Imperfectly drained: some soil horizons remain wet for periods of several weeks. • Moderately well drained: some soil horizons remain wet for a week after water addition. • Well drained: no horizon remains wet for more than a few hours after water addition. • Rapidly drained: no horizon remains wet except shortly after water addition. Duplex soil See Texture contrast soil. Dystrophic See Base status. Earths Soils with a sandy to loamy (including clay loam) surface soil, gradually increasing to a loamy to light clay subsoil. - masszve Earths in which the subsoil is not arranged into natural soil aggregates and appears as a coherent, or solid mass. - structured Earths in which the subsoil is arranged into natural soil aggregates which can be clearly seen. Effe ctive rooting Depth to which most plant feeder roots will penetrate. This is depth (ERD) taken here to be the depth either to which salts have been leached and have therefore accumulated, or to an impeding layer. This represents the long-term depth of wetting. Ep icalcareous A soil in which the major part ofthe top 0.5 m of the profile is calcareous. It is used to describe Vertosols in the Australian Soil Classification (Isbell 1996). Ep ihypersodic Soils with at least one subhorizon within the top 0.5 m of the profile having an ESP greater than 15. It is used as a Subgroup definition forV ertosols in the Australian Soil Classification (Isbell 1996). 163 Glossary Electrical conductivity A measure of the conduction of electricity through water, or a (EC) water extract of soil. The value can reflectthe amount of soluble salts in an extract and therefore provide an indication of soil salinity. Erodibility The susceptibility of a soil to the detachment and (soil) transportation of soil particles by erosive agents. It is a function of the mechanical, chemical and physical characteristics of the soil, and is independent of the other factors influencing soil erosion such as topography, land use, rainfall intensity and plant cover. It may be changed by management. Erosion hazard The susceptibility of a parcel of land to the prevailing agents of erosion. It is dependent on a combination of climate, landform, soil, land use and land management factors. ESP Exchangeable sodium percentage. See Sodicity. Eutrophic See Base status. Feldspar Any of a group of alkaline aluminium silicate minerals. An important part of igneous rocks, such as granite. Floristic association The dominant or diagnostic species used to classify vegetation. Gradational The term describes a soil with a gradual increase in texture (i.e. becomes more clayey) as the profile deepens. Granite/granitic rocks A coarse-grained, igneous rock formed beneath the earth's surface and consisting essentially of 20-40% quartz, alkali feldspars (which are a source of sodium and potassium) and very commonly a mica. Gypsum A naturally occurring soft crystalline material which is a hydrated form of calcium sulphate. Gypsum contains approximately 23% calcium and 18% sulfur. It is used to improve soil structure and reduce crusting in hard setting clayey soils. 164 Glossary Hap lie A term used in the Australian Soil Classification (Isbell 1996) which indicates that the major part of the upper 0.5 m of the soil profile is whole coloured. Hard setting Surface soil that becomes hard and apparently structureless on the periodic drying of the soil. Horizon See Soil horizon, also Soil horizon boundary. Hyp ercalcic These soils have a B horizon or subsurface layer containing more than 20% of mainly soft, finely divided carbonate, and less than 20% of hard calcrete fragments and/or carbonate nodules, and/or carbonate coated gravel. The term is used as a definition for a number of Orders in the Australian Soil Classification (Isbell 1996). Igneous rocks Rock crystallised from molten rock material (magma). It may be extruded to the Earth's surface (volcanic) or cool at variable depths below the surface (intrusive, and plutonic). Infiltration Themovement of water through the soil surface. Soils with a high infiltration capacity allow more rain to enter the soil than soils with a low capacity. Runoff will occur when the rate of rainfall exceeds the soil's infiltration capacity. Surface soil structure and texture are important determinants of the infiltration capacity of a soil. Jump up s Local term used to describe stony, lateritised ridges and scarps. Kandosol A Soil Order of the Australian Soil Classification (Isbell 1996). These soils lack strong texture contrast andhave massive or only weakly structured B horizons. The B2 horizon is well developed and has a maximum clay content in some part of the B2 horizon which exceeds 15%. They are also not calcareous throughout. Kaolinisation Breakdown of minerals (particularly feldspars) under intense weathering to form kaolinite clay (china clay). See also Laterite. 165 Glossary Kurosol A Soil Order of the Australian Soil Classification (Isbell 1996). These soils have a clear or abrupt textural B horizon in which the major part of the top 0.2 m of the B2 horizon is strongly acid i.e. less than pH 5.5 (water). Laterite A profile formed by intense weathering. Many deeply weathered profiles termed 'lateritic' exhibit a distinct series of layers including a surface duricrust, ironstone and mottled and pallid (kaolinised) zones. The word laterite is used for any profile in which ironstone is a majorfea ture. See Duricrust. Lateritisedrocks Rocks which have been partially or completely weathered to laterite. Leaching The removal in solution of soluble minerals and salts as water moves through the soil profile. Local relief The altitude difference between the base and crest of slopes in undulating or hilly areas. Magnesic Soils with an exchangeable Ca/Mg ratio of less than 0.1 in the major part of the B2 horizon. This term is used as a definition within a number of Soil Orders in the Australian Soil Classification (Isbell 1996) . Massive earths See Earths, massive. Massive structure See Soil structure, ap edal. Mesonatric Soils in which the major part of the upper 0.2 m of the B2 horizon has an ESP between 15 and 25. Used as a Great Group definition for Sodosols in the Australian Soil Classification (Isbell 1996). Metamorphic rocks Rocks that were originally igneous or sedimentary that have been physically and/or chemically altered by high temperatures and/orpressures beneath the Earth's surface. Mineralisation The breakdownof soil organic matter and crop and animal residues by micro-organisms to inorganic (available) forms. 166 Glossary Mottle Spots, blotches or streaks of subdominant colours different from the main soil colour. My corrhizae Soil fungi which act as rootlets and increase the amount of nutrients (particularly phosphorus and zinc) available to plants. Fallowing, excessive tillage and soil fumigation can cause mycorrhizae to die out. Plants growing with mycorrhizae are generally healthier and more resistant to disease, particularly root rots. Natric Soils in which the major part of the upper 0.2 m of the B2 horizon is sodic. Used as a Great Group definition for Kurosols in the Australian Soil Classification (lsbell 1996). Nodules (in soil) See Segregation. Non-cracking clays See Clays, non-cracking. Orthic Soils which usually have a weakly developed B horizon (in terms of contrast between A horizons above and adj acent horizons below), or a B horizon with 15% clay (SL-) or less, or a transitional horizon (C/B) occurring in fissures in the parent rock which contains between 10 and 50% of B horizon material (including pedogenic carbonate). Pans A hard and/or cemented soil horizon e.g. cultivation pan. Paralithic A term used in the Australian Soil Classification (Isbell 1996) to define soil material which directly overlies partially weathered or decomposed rock or saprolite. Parent material The rock from which a soil profile develops. Permeability The capacity for transmission under gravity of water through soil or sediments. Plant available water The quantity of water held in a soil that can be extracted by capacity (PA WC) plant roots. It is expressed as millimetres of plant available water within the root zone. pH A measure of the acidity or alkalinity of a soil. A pH of 7.0 indicates neutrality, higher values indicate alkalinity and lower values indicate acidity. Each unit change in pH represents a 167 Glossary 10-fold change in either the acidity or alkalinity of the soil. For example, a pH of 5.0 is 10 times more acid than a pH of 6.0. Soil pH affects the amount of different nutrients that are soluble in water and therefore the amount of nutrient available to plants. Porosity (of soil) The degree of pore space in a soil (i.e. the percentage of the total space between solid particles). The extent and type of soil porosity indicates the ease with which water, air and roots can move through the soil. Without sufficient pores of the right size, soil is unproductive because plant roots cannot move through the soil easily, air and water movement are poor, and there is insufficient water for plant growth. There are two types of pores. Macropores are large pores, greater than 0.03 mm in diameter, and most can be seen by the naked eye. They include the spaces between soil aggregates caused by cultivation, shrinking and cracking, channels made by roots of plants, and earthworm and other animal and insect tunnels. Macropores are vitally important in allowing water and air to move freely, but provide little water for plant uptake because they are readily drained. Micropores are small pores less than 0.03 mm in diameter occurring mainly within aggregates. Water drains through themvery slowly so they act as water reservoirs for plant roots. Regolithic A term used to describe soils with a layer of unconsolidated mineral material beneath the soil profile. The term is used in the Australian Soil Classification (Isbell l996). Salinity Thepresence of sufficient soluble salts to adversely affect plant growth and/or land use. The main salt involved is sodium chloride, but sulfates, carbonates and magnesium salts occur in some soils. It is expressed as a level of electrical conductivity (EC). See Electrical conductivity. Sands Soils with a uniform sand (including sandy loam) texture throughout the surface soil and subsoil. Saprolite Decomposed rock that has maintained characteristicsthat were present as an unweathered rock. 168 Glossary Sedimentary rocks Rocks formed from the accumulation of material which has been weathered and eroded from pre-existing rocks, then transported and deposited as sediment by wind (aeolian) or water (fluvial, marine). Sedimentary rocks have been classified according to grain size and constituent minerals: Clay-sized grains Mudstone Silt-sized grains Siltstone Sedimentary rocks Sand-sized grains Sandstone Gravel-sized grains Conglomerate Sandstone is further subdivided on the basis of the dominant minerals making up the clasts (solid inclusions) or the matrix which cements the clasts together: 90% or more of grains are quartz: Quartzose sandstone Sandstone -[ less than 75% of grains are quartz: Labile sandstone Segregation Discrete accumulations of minerals in the soil because of the concentration of some constituent, usually by chemical or biological action. Segregations are described by their nature, abundance and form. 1) nature for example, calcareous (carbonate), gypseous (gypsum), manganiferous (manganese) and ferromanganiferous (iron manganese). 2) abundance very few (trace or occasional) <2% few (slight) 2- 10% common (light) 10-20% many (moderate) 20-50% very many (heavy) >50% 3)form concretions - spheroidal formations (concentric in nature). nodules - irregularrounded formations (not concentric or symmetric). Can have a hollow interior. 169 Glossary fragments - broken pieces of segregations. crystals - single or complex clusters of visible crystals. soft segregations - finely divided soft segregations accumulated in the soil through chemical action with water. They contrast with surrounding soil in colour and composition but are not easily separated from the soil as separate bodies. Self-mulching A condition of well-structured surface soil, notably of clays, in which the aggregates fall apart naturally as the soil dries to form a loose mulch of soil aggregates. In cultivated soils, ploughing when wet may appear to destroy the surface mulch which, however, will re-form upon drying. Slickensides Subsoil structural features which develop as a result of two masses moving past each other, polishing and smoothing the surfaces. Theseare common in Vertosols. Sodicity A characteristic of soils (usually subsoils) containing exchangeable sodium to the extent of adversely affecting soil stability, plant growth and/or land use. It is measured as a percentage of the cation exchange capacity of the soil. The classes are defined as follows: non-sodic - less than 6% sodic - between 6% and 15% strongly sodic -more than 15% Sodic or strongly sodic soils would be dispersible andmay be improved by the addition of gypsum. Sodosol A Soil Order of the Australian Soil Classification (Isbell 1996). These soils have a clear or abrupt textural B horizon in which the major part of the upper 0.2 m of the B2 horizon is sodic and is not strongly subplastic. Soft segregations See Segregation. (in soil) 170 Glossary Soil colour The colour of soil material is determined by comparison with a standard Munsell soil colour chart. The colours are described for moist soils unless otherwise stated. Soil depth The following depth ranges are used in this manual to describe the soil surface and soil profile depths. 1) soil suiface thin 0-15 em moderately thick 15-30 em thick 30-60 em very thick >60 cm 2) soil profile very shallow <25 em shallow 25-50 em moderately deep 50-100 em deep 100-150 em very deep 150-500 em Soil horizon A layer of soil material within the soil profilewith distinct characteristics and properties produced by soil-forming processes, and which are different from those of the layers above and/or below. The three mainhor izons are: A (topsoil); B (subsoil); C (see C horizon). Soil horizon boundary Boundaries between horizons take many forms. The terms used in the soil descriptions of the Field Manual soil photographs and Appendix 3 (Resource Information) are: Sharp - less than 5 mm wide; Abrupt - 5 to 20 mm wide; Clear - 20 to 50 mm wide; Gradual - 50 to 100 mm wide; Diffuse - more than 100 mm wide. Soil profile A vertical cross-sectional exposure of a soil, from the surface to the parent material or Substrate. Soil reaction trend The general direction of the change in pH with depth. 171 Glossary Soil structure The arrangement of natural soil aggregates that occur in soil� structure includes the distinctness, size and shape of these aggregates. 1) distinctness - strong The natural soil aggregates are quite distinct in undisplaced soil� when displaced more than two-thirds of the soil material consists of aggregates (i.e. well structured). -moderate Natural soil aggregates are well formed and evident but not distinct in undisplaced soil� when displaced more than one third of the soil material consists of aggregates (i.e. moderate! y structured). -weak The natural soil aggregates are indistinct and barely observable in undisplaced soil� when displaced up to one-third of the soil material consists of soil aggregates (poorly structured). 2) size -coarse The natural soil aggregates are relatively large� an average size of 20 mm or more is coarse for the purposes of this manual. -medium The average size of the natural soil aggregates is between fine and coarse. -fine The natural soil aggregates are relatively small� an average size of 5 mm or less is fine for the purposesof this manual. 3) shape - apedal There are no observable natural soil aggregates (structureless)� the soil may be either a coherent mass (massive) or a loose, incoherent mass of individual particles such as sand grains (single grain). -blocky The natural soil aggregates have the approximate shape of cubes with flat andslightly rounded sides. -prismatic The natural soil aggregates have the approximate shape of elongated blocks. 172 Glossary - columnar The natural soil aggregates are like those of prismatic but have domed tops. -polyhedral Thenatural soil aggregates are irregular, many sided and multi angled. -lenticular The natural soil aggregates are like large vertical lens shapes with curved cracks between the aggregates. -platy The soil particles are arranged around a horizontal plane and bounded by relatively flat horizontal faces. - granular The natural soil aggregates are rounded, porous, stable and less than 12 mm in diameter. They usually occur in the surface horizons. Soil texture The coarseness or fineness of soil material as it affects the behaviour of a moist ball of soil when pressed between the thumb and forefinger. It is generally related to the proportion of clay, silt and sand within a soil. Texture classes used in this manual are defined primarily by the total clay content: Group Clay content (%) Coarse Sand less than 5 Loamy sand 5 to 10 Sandy loam 10 to 20 Medium Loam z25 Sandy clay loam 20 to 30 + sand Clay loam 30 to 35 Fine Sandy clay 35 to 40 + sand Light clay 35 to 40 Medium clay 40 to 50 Heavy clay more than 50 Solodic soils Soils with strong texture contrast between A horizons and sodic B horizons which are not strongly acid. Structural fo rmation Vegetation grouping based on attributes of the tallest layer e.g. class (of vegetation) growth form, crown separation and height. Structured earths See Earths, structured. 173 Glossary Subnatric A Great Group of the Australian Soil Classification (Isbell 1996). A major part of the upper 0.2 m of the B horizon has an ESP between 6 and less than 15. Thesesoils are considered to be sadie (See Sodicity). Subsoil Soil layers below the surface with one of the following attributes: -alarger content of clay, iron, aluminium, organic material (or several of these) than the surface and subsurface soil� - stronger colours than those of the surface and subsurface soil above, or the substrate below. The B horizon. Substrate The material below the soil profile which may be the parent material or may be unlike the material from which the soil has formed� substrate which is not parent material for the soil above may be layers of older alluvium, rock strata unrelated to the soil or the buried surface of a formerland scape. Subsurfa ce soil Soil layers immediately under the surface soil which usually have less organic matter, paler colours and may have less clay than the surface soil. The A2 horizon. Surface crust Distinct surface layer, oftenlami nated, ranging in thickness from a few millimetres to a few tens of millimetres, which is hard and brittle when dry and cannot be readily separated from and lifted off the underlying soil material. Surface soil The soil layer extending from the soil surface down which has some organic matter accumulation and is darker in colour than the underlying soil layers. The A horizon. Tenosol A Soil Order of the Australian Soil Classification (Isbell 1996). These soils generally have weak pedological organisation throughout the profile apart from the A horizons. Texture See Soil texture. Texture contrast soil A soil in which there is a sharp change in soil texture between the A and B horizons (surface and subsoil) over a distance of 10 em or less. Also known as a duplex soil. 174 Glossary Traprock A popular term used to describe a complex mixture of highly deformed sandstone and mudstone, interbedded conglomerate, limestone andvolcani cs. Uniform clays See Clays. Vertosol A Soil Order of the Australian Soil Classification (Isbell 1996). These are clay soils with shrink/swell properties that display strong cracks when dry and have slickensides and/or lenticular structural aggregates at depth. Vo lcanic rocks Igneous rocks which have cooled from magma extruded to the Earth's surface. The size of the rock crystals depends on its duration of cooling - rapid cooling forms very fine crystals or even volcanic glass. -acid Contain 10% or more quartz and proportions of magnesium, iron and calcium. Usually light coloured. -·basic · Basalt or basaltic rocks containing minimal or no quartz. Usually dark coloured because of a high proportion of iron and manganese minerals. ,_, int£:rmediate Contain less than 10% quartz and mixed amounts of other minerals that are intermediate between the typical acid and basic igneous rocks. Waterlogging A situation in which all the pores in the soil have filledwith water. Excess water may lie on the surface of the soil. All the air in the pores has been displaced by water, so no oxygen is available to plant roots or for soil microbial activity. If waterlogging continues for a long period, plants die. Under waterlogged conditions, nitrate, the most available formof nitrogen, breaks down and is lost as a gas. Workability The ease or otherwise of working the soil with machinery. 175