Flora Survey, Glen Innes Management Area, Northern Region
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This document has been scanned from hard-copy archives for research and study purposes. Please note not all information may be current. We have tried, in preparing this copy, to make the content accessible to the widest possible audience but in some cases we recognise that the automatic text recognition maybe inadequate and we apologise in advance for any inconvenience this may cause. FOREST RESOURCES SERIES NO. 23 FLORA SURVEY, GLEN INNES MANAGEMENT AREA, NORTHERN REGION BY DOUG BINNS , ,ft~:t'" , , , FORESTRY COMMISSION OF NEW SOUTH WALES .,, / t' \ FLORA SURVEY, GLEN INNES MANAGEMENT AREA NORTHERN REGION by ~, , DOUGBINNS FOREST ECOLOGY AND SILVICULTURE SECTION RESEARCH DIVISION FORESTRY COMMISSION OF NEW SOUTH WALES SYDNEY 1992 Forest Resources Series No. 23 October, 1992 , . , Published by: Forestry Commission ofNew South Wales, Research Division, 27 Oratava Avenue, West Pennant Hills, 2125 P.O. Box 100, Beecroft 2119 Australia. Copyright © 1992 by Forestry Commission ofNew South Wales ODC 17--05(944) ISSN 1033-1220 ISBN 0 7305 9649 4 J-' L Flora Survey, Glen Innes Management Area. -i- Northem Region TABLE OF CONTENTS PAGE INTRODUCTION 1 METHODS 1 1. Plot!.JOcation ; 1 2. Floristic and Vegetation Structural Data .4 3. Habitat Data ; 4 4. Limitations 4 5. Taxonomy andNomenclature 5 6. Data Analysis 6 RESULTS 6 1. Floristics 6 2. Overstorey Communities : 7 3. Comparison ofNew South Wales Forestry Commission Forest Types as Mapped .. 12 and Overstorey Floristic Communities 4. Non-eucalypt (tlUnderstorey") Floristic Communities 14 5. !.JOgging Impact 17 6. Fire Impact 18 DISCUSSION 18 1. General 18 2. Significant Plant Species 18 3. Conservation Status ofPlant Communities 25 4 Impact of!.JOgging 29 5. Impact ofFire 29 6. Impact ofGrazing 30 . 7. Weeds 30 ACKNOWLEDGEMENTS 30 REFERENCES 31 TABLES Table 1. Distribution ofplots by map unit and overstorey communities 13 Table 2. Distribution ofplots by overstorey and understorey communities 16 .~ < Table 3. Comparison ofeucalypt forest types ~ 27 't4 r FIGURES Figure lA. Locations ofsurvey plots 2 Figure lB. Locations ofsurvey plots 3 Figure 2. Dendrogram at the 29 class level, for overstorey 8 Forest Resources Series No. 23 Forestry Commission ofNew South Wales ;-----------------------------------~ -- - -- Flora Survey, GlenInnes Management Area, Northern Region -ii- Figure 3. Dendrogram at the 35 class level, for understorey 15 Figure 4. Scatterplot ofMDS, co-ordinates group 1, logging history superimposed 19 Figure 5. Scatterplot ofMDS, co-ordinates group 2, logging history superimposed 20 Figure 6. Scatterplot ofMDS, co-ordinates group 1, fire history superimposed 21 Figure 7. Scatterplot ofMDS, co-ordinates group 2, fire history superimposed 22 APPENDICES ) Appendix 1. Taxonomic list ofvascular plant species 32 Appendix 2. Frequency ofoccurrence ofplant species in State Forests 52 Appendix 3. Frequency ofoccurrence ofplant species by vegetation type 69 Appendix 4. Descriptions offloristic communities 83 Appendix 5. Descriptions ofForest Type map units 96 ) r Forestry Comniission ofNew South Wales Forest Resources Series No. 23 Flora Survey, Glen Innes Management Area, -1- Northern Region INTRODUCTION This report presents the results ofa flora survey undertaken in the State Forests ofGlen Innes Management Area, on the northern tableland and escarpment north and east ofGlen Innes, New South Wales. This area is described by the Forestry Commission ofNew South Wales (1986). The survey was in the context ofmanagement ofthe area for commercial forestry purposes. Most ofthe field work was carried out by D. Binns and T. Brassil, with some assistance from T. Tweedie, during April 1991 and August 1991. METHODS 1. Plot Location Floristic data were derived from a series ofnon-permanent plots established within the study area. Plots were initially marked on 1:25 000 topographic maps using stratified random sampling. Plot points in previously unlogged areas were stratified primarily by vegetation type, on the basis ofmaps ofForest Types (Forestry Commission ofNew South Wales, 1989) previously prepared from aerial photograph interpretation with extensive field checking (Forestry Commission ofNew South Wales unpubl. maps). Numbers ofplots per Forest Type were allocated according to variability ofgeological substrate and total extent oftype. A single plot was located in the least extensive types and up to four plots in the most extensive types. For each ofthe most extensive types, up to six plots were also located in previously logged areas. In Butterleaf State Forest and the northern part ofCurramore State Forest, for which vegetation maps do not exist, plots were located subjectively to sample a range of habitat types. Forest Types have not been mapped over large areas ofsteep to precipitous topography on the eastern escarpment. These areas are ofnegligible interest for commercial forestry, and preliminary field inspection suggested that extensive areas were floristically relatively uniform and were also likely to be oflittle botanical interest. Sampling intensity in these areas was very low and aimed at minimum representation ofmajor vegetation types plus sampling ofthe small areas of particular interest, such as rainforest patches and rock outcrops. An excess ofplots was marked in more extensive strata. Final sample plots were chosen from these to favour plots which could be sampled en route to those in less extensive strata. This strategy was designed to ensure efficient sampling ofthe full range ofhabitats while reducing unproductive travelling time as far as possible. Final plot positions were transferred to the field as accurately as possible using topographic features. Plots were located to ensure that each geology type in the area was sampled. In the field, plots were positioned as far as possible within a relatively homogeneous patch of vegetation. The standard size was a 50 m x 20 m (0.1 ha) rectangle, although some habitats required a variation in size or shape to ensure homogeneity within one plot e.g. longer or narrower plots were used for riparian vegetation, and smaller plots for vegetation ofrestricted extent. A total of82 plots was surveyed during the present survey. Approximate locations are shown in Figures lA and lB. Some additional floristic data were available from limited surveys in London Bridge State Forest by T. Tweedie (Watts and Tweedie, pers. comm.). These data have been included where appropriate, but were not sufficiently compatible to be used for community analysis. Additional overstorey data ( (estimates ofbasal area using optical wedge counts) were available from habitat measurements for an owl survey being undertaken in the area (R. Kavanagh,pers. comm.). These have been included in the overstorey analysis. Forest Resources Series No. 23 Forestry Commission o(New South Wales Flora Survey, Glen Innes Management Area, Northern Region -2- 1$2'.' I .. ) DL..' ........i'4k. ) J Figure lA. Approximate locations offlora survey plots, Glen Innes Management Area. ButterleafState Forest, Curramore State Forest, Gibraltar Range State Forest, Glen Elgin State Forest, Moogem State Forest, Mt. Mitehell State Forest. Forestry Commission ofNew South Wales Forest Resources Series No. 23 Flora Survey, GlenInnes Management Area, -3- Northern Region E '!Q .. ... ~ I J z~ + "+ J ...... N ( Figure lB. Approximate locations offlora survey plots, Glen Innes Management Area, BrotherState Forest, Glen Nevis State Forest, London Bridge State Forest, Oakwood State Forest, Torrington State Forest, Warra State Forest, Forest Resources Series No. 23 Forestry Commission ofNew South Wales Flora Survey, Glen Innes Management Area, Northern Region -4- 2. Floristic and Vegetation Structural Data All plant species which could be distinguished within a plot were recorded and identified as far as possible to species level. Vertical heights ofvegetation strata were subjectively defined and recorded for each plot. Stratum limits of0-1 m, 1-6 m, 6-20 m and 20-35 m and >35 m were used as a guide for the coding ofstructural data, even though actual heights were recorded. Cover codes, based on projected canopy cover, were estimated for each species within each vertical stratum. Where a species occurred in more than one stratum, an overall cover code for the plot as a whole was also recorded. Codes are as follows: Cover Code Projected Canopy Cover 1 < 5%, few individuals 2 < 5%, any number ofindividuals 3 6-25% 4 26-50% 5 51-75% 6 >75% The locations ofany occurrences ofsignificant species noted while traversing the area, additional to those occurring in plots, and any species not previously recorded in plots, were also recorded. The map unit in which each plot was located was recorded and a subjective assessment made ofthe Forest Type (Forestry Commission ofNew South Wales, 1989) to which the vegetation would be most appropriately allocated. .... 3. Habitat Data At each plot, slope (in degrees), altitude, aspect, topographic position, drainage, percentage cover and particle size ofsurface rock and cover ofoutcropping bedrock were recorded. An assessment was made ofprevious disturbance by logging, fire and grazing, on the basis ofany available visual evidence. An estimate ofintensity and time since disturbance was recorded. Estimates for logging were checked against historical records. Any other unusual feature was also recorded. 4. Limitations Field work was carried out in autumn and late winter. Some ephemeral species may have been overlooked, and spring or summer flowering geophytes, including