BOX‐IRONBARK

in Victoria’s State Forests

Silviculture Reference Manual No. 4

Peter Fagg and Owen Bassett

Department of Economic Development, Jobs, Transport and Resources Victoria, Australia

ii Box‐Ironbark Silviculture Reference Manual

Manual prepared by Forest Solutions Pty Ltd for the State of Victoria www.forestsolutions.com.au

© The State of Victoria Department of Economic Development, Jobs, Transport and Resources 2015

This work is licensed under a Creative Commons Attribution 4.0 licence. You are free to re‐use the work under that licence, on the condition that you credit the State of Victoria as author. The licence does not apply to any images, photographs or branding, including the Victorian Coat of Arms, the Victorian Government logo and the State of Victoria logo. To view a copy of this licence, visit http://creativecommons.org/licenses

ISBN 978‐1‐74146‐438‐2 (pdf)

ISBN 978‐1‐74146‐571‐6 (Print)

This publication may be referenced as:

Fagg, P.C. and Bassett, O.D. (2014). Box‐Ironbark in Victoria’s State Forests, Silviculture Reference Manual No. 4, Department of Economic Development, Jobs, Transport and Resources, Melbourne, Victoria.

Disclaimer This publication may be of assistance to you but the State of Victoria and its employees do not guarantee that the publication is without flaw of any kind or is wholly appropriate for your particular purposes and therefore disclaims all liability for any error, loss or other consequence which may arise from you relying on any information in this publication.

Box‐Ironbark Silviculture Reference Manual iii

Foreword

A task that is common to many areas of scientific endeavor is the challenge of maintaining and extending a wealth of scientific and technical knowledge. Applying that knowledge, combined with hard‐learned lessons, is testing but rewarding. It is a privilege to introduce the Box‐Ironbark in Victoria’s State Forests ‐ Silviculture Reference Manual No. 4, a book that consolidates silvicultural knowledge developed over several decades in this forest type. A rush of human settlement followed the discovery of gold in the 1850s. Large tracts of Box‐Ironbark forest overlaid the alluvial and underground mines. These forests provided the basic necessities of energy, shelter and structural timbers for the new arrivals. Relatively gentle topography made it practicable for timber harvesting and clearing to expand throughout the range of the central Victorian Box‐Ironbark forests, and resulted in a fundamental shift in forest structure. The magnitude of this change is difficult to quantify and is arguably speculative, as it is based on scant, historical accounts. However, in comparison with the pre‐European Box‐Ironbark forests, it is likely that today’s forests are characterised by much younger and denser stands of smaller trees. Over time, Box‐Ironbark State forest management has changed from unregulated resource use to conservation of growing stock. In relatively recent times, advances in silvicultural and ecological understanding have enabled the introduction of scientifically‐based control of stocking, age cohorts and management of multiple objectives, including timber production, wildlife and tourism. Over the last 150 years there have been changes in forest tenure and management activities as a result of research and community demands. However, it will take more time to address some historical negative impacts; for example, from mining, and the desired end‐points may shift again in the future with changing community expectations. The effort, knowledge and experience of the authors has resulted in a valuable resource for current and future managers of Box‐Ironbark in both State forest and conservation reserves, which will help them exercise options and choices with this knowledge as a foundation stone. Hopefully it will also provide inspiration for further research.

Jon Cuddy November 2014

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Jon Cuddy B.Sc. (For.) (ANU) Jon started his forestry career in plantation softwood harvesting in Scottsdale, Tasmania, in 1981. In 1990 he moved to Benalla in north east Victoria and commenced in a native forest management role with the Victorian Department of Conservation and Environment. Most of his career has since involved forest management planning for the River Red Gum forests of northern Victoria and the Box–Ironbark forests of central Victoria. He was a co‐author of the 1993 Statement of Resources, Uses and Values for the Mid‐Murray Forest Management Area. In the Box‐Ironbark region, Jon has undertaken key management and planning tasks aimed at continuous improvement of the forests in that area. He has been based in Bendigo, in many ways the center of Victorian Box‐Ironbark forests, for over 15 years. Jon’s current role is Project Leader, Emergency Management, based in Bendigo with the Department of Economic Development, Jobs, Transport and Resources.

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Dedication This manual is dedicated to the memory of Jim Allen, a Forest Overseer and later a Forest Planner who spent many years of his career in Victoria’s Box‐Ironbark forests.

(28 July 1952 ‐ 7 July 2014)

Born in Ararat in 1952, Jim’s first job was a used car salesman in Ballarat, but he gave that up for a job with the Ballarat Forests Commission summer crew. District Forester Jeff Brisbane, recognising Jim’s interests and talents, kept him on as a permanent employee from 1977. On Jeff’s recommendation, Jim was accepted into the Victorian School of Forestry in Creswick in 1980 to commence the Certificate of Applied Science in Conservation and Resource Management. He became a Forest Overseer after completing his studies in 1982, having been posted to the Castlemaine District in 1981. Whilst at Castlemaine, one of Jim’s main tasks was to manage the domestic firewood house block system, where residents were allocated a small block of Box‐Ironbark forest to thin out and produce their own firewood. Jim took great care and pride in how he marked the forest, ensuring it would remain sustainable well into the future. In 1994, Jim became a Forest Planner based in Bendigo, where one of his major roles was to produce the Wood Utilisation Plan for the Box‐Ironbark and Red Gum forests in that region. It was a job he did very well due to his solid understanding of forest management and utilisation. Jim was also a valued member of the Box‐Ironbark and Red Gum Research and Development Action Group, and the State‐wide Silviculture Working Party for some years. One of his greatest attributes was his ability to get along with and calm people, no matter how upset they were. No one ever had a bad word to say about Jim. He was a kind and gentle man who cared deeply for his family and the many people he befriended. Jim was much more than a work colleague, he was a friend and a mate to all who knew him. Jim moved to the Department of Primary Industries (DPI) when the responsibility of commercial timber harvesting transferred from the Department of Sustainability and Environment (DSE) to DPI, and was appointed Forestry Operations Manager in July 2012. He retired from the DPI in 2013 after 36 years of dedicated service to both the forests and the public of Victoria. Jim’s premature death in July 2014, after a battle with brain cancer, was a huge loss to his family and friends.

vi Box‐Ironbark Silviculture Reference Manual

The Authors

Peter Fagg Dip.For. (Cres.), B.Sc.(For). (Melb.), MIFA For most of his career with Victorian Government forestry agencies, Peter has specialised in silviculture. His role encompassed policy development, knowledge transfer and the documentation of operations such as regeneration reforestation, seed management, thinning and fire recovery within Victorian native State forests. Peter previously carried out applied silvicultural research, largely with the Forests Commission of Victoria, in the period 1971‐1989. In East Gippsland he investigated the impacts of the Cinnamon Fungus and the regeneration of mixed species forests. State‐wide projects included weed control research in plantations, the Young Eucalypt Program in association with CSIRO, and DSE’s Silvicultural Systems Project. Peter has authored or co‐authored over 50 publications and, having retired from the Department of Sustainability and Environment in late 2010, is currently a part‐time forestry consultant, associated with Forest Solutions Pty Ltd.

Owen Bassett B.For.Sci. (Melb.), MIFA Owen is the founding Director of Forest Solutions Pty Ltd, a private consultancy that provides silviculture advice to organisations managing native eucalypt forests. Since 2008, Owen has completed a number of Victorian Government projects, including a review of commercial forestry in western Victoria, and the recovery of young Ash forests following numerous bushfires. His major clients include the former Department of Environment and Primary Industries, VicForests, Parks Victoria, Department of Environment, Land, Water and Planning and HVP Plantations.

Owen has specialised in native forest silviculture since graduating in 1987. He began his career in research, studying eucalypt seed development during the Silvicultural Systems Project (SSP). In the early 1990s he began what is today one of the world’s longest, continuous floral monitoring studies for a forest tree species (E. regnans forests of the Central Highlands). Owen also spent nearly two years with Forestry Tasmania (1996‐1998), undertaking silvicultural research at the Warra LTER site. He has authored or co‐authored over 30 publications.

Box‐Ironbark Silviculture Reference Manual vii

Table of Contents

1. INTRODUCTION 1 1.1 The Box‐Ironbark forest type in Victoria 1 1.1.1 What are Box‐Ironbark forests? 2 1.1.2 Area and distribution of Box‐Ironbark forests in Victoria 3 1.2 General features of Box‐Ironbark forests 6 1.2.1 Species composition, density and size 6 1.3 Climate 7 1.4 Genetic factors 9 1.5 History of forest use and management 10 1.5.1 Pre‐settlement forests 10 1.5.2 The mining industry 11 1.5.3 The agricultural industry 11 1.5.4 The timber industry 12 1.5.5 The eucalyptus oil industry 14 1.5.6 The charcoal industry 15 1.5.7 The apiary (bee‐keeping) industry 16 1.6 Current timber production 17 1.7 Silvicultural research and development in Box‐Ironbark 18

2. Ecology 21 2.1 Aspects of the Box‐Ironbark ecosystem 21 2.1.1 Flora 21 2.1.2 Fauna 23 2.1.3 Geology, soils and nutrition 30 2.1.4 Hydrology 31 2.2 Ecosystem dynamics 31 2.2.1 Fire ‐ its role and influence 31 2.2.2 Storms 32 2.2.3 Organisms that may reduce tree growth 33 3. Silvical features of Box‐Ironbark eucalypts 40 3.1 Sources of regeneration 40

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3.1.1 Seedlings 40 3.1.2 Lignotuberous seedlings 42 3.1.3 Coppice 42 3.2 Seed production 43 3.2.1 Flowering and seed development 43 3.2.2 Seed quantities 53 3.2.3 Seed type and dissemination 53 3.2.4 Seed collection and storage 55 3.2.5 Seed viability, vitality, dormancy and susceptibility to heat 57 3.3 Factors affecting seedling establishment 60 3.3.1 Seed survival and protection 60 3.3.2 Timing of sowing/seedfall, and germination 60 3.3.3 Seedbed type and competition 61 3.3.4 Frost and fire 62 3.3.5 Browsing animals 62 3.4 Stand and tree growth 63 3.4.1 Growth rates 63 3.4.2 Growth response to thinning 63 3.4.3 Branch and crown development 65 3.4.4 Root and mycorrhizae development 65 4. Selection of silvicultural systems 67 4.1 Strategic planning 67 4.2 Silvicultural systems for different objectives 67 4.2.1 Timber production 70 4.2.2 Water production 70 4.2.4 Flora and fauna conservation 71 4.2.5 Landscape management 72 4.3 Decision support systems 72 4.4 To salvage or not to salvage? 73

5. Silvicultural systems and practices 74 5.1 Single tree selection 74 5.1.1 Description 74 5.1.2 Marking and harvesting 75 5.1.3 Site preparation 76 5.1.4 Regeneration and its protection 76

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5.1.5 Performance measurement 76 5.1.6 Flora and fauna conservation 77 5.2 Group selection 77 5.2.1 Description 77 5.2.2 Marking and harvesting 78 5.2.3 Site preparation 78 5.2.4 Regeneration and its protection 78 5.2.5 Performance measurement 79 5.2.6 Flora and fauna conservation 79 5.3 Coppice with standards 79 5.3.1 Description 79 5.3.2 Marking and harvesting 81 5.3.3 Site preparation 82 5.3.4 Regeneration and its protection 82 5.3.5 Performance measurement 82 5.3.6 Flora and fauna conservation 82 5.4 Thinning (commercial) 83 5.4.1 Description 83 5.4.2 Marking and harvesting 83 5.4.3 Stump and coppice competition 85 5.4.4 Performance measurement 85 5.4.5 Flora and fauna conservation 85 5.5 Thinning (pre‐commercial) 86 5.6 Ecological thinning 87 5.6.1 Description 87 5.6.2 Planning 88 5.6.3 Methods of ecological thinning treatment 89 5.6.4 Performance measurement 90 5.6.5 Flora and fauna conservation 91 6. Reforestation and remedial regeneration 92 6.1 Reforestation/rehabilitation 92 6.2 Remedial (or backlog) regeneration 94 6.2.1 Procedures 94 6.2.2 Performance measurement 96 References 97

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APPENDIX A ‐ Prescriptions regarding Phytophthora 112 APPENDIX B ‐ Indices of Flowering Behaviour 112 APPENDIX C ‐ Sawlog Tree Specifications 114 APPENDIX D ‐ Silviculture Decision Support System 114 APPENDIX E ‐ Habitat prescriptions 119 Acknowledgements 121 Glossary 122 Index 132

Box‐Ironbark Silviculture Reference Manual 1

1. INTRODUCTION

1.1 The Box‐Ironbark forest type in Victoria Spread intermittently from Chiltern in the north east of Victoria to Stawell in the west, with isolated pockets near Melbourne and in Gippsland, the vegetation ‘grouping’ known as Box‐Ironbark forest or woodland is well known and appreciated (Figure 1). Although the extent of this forest type in Victoria is relatively limited, these iconic forests contribute significantly to ecological, social and economic values in their local communities, including: 1. the conservation of flora and fauna 2. the protection of landscape and historic values 3. the provision of recreational and educational opportunities 4. the provision of timber and other forest products, such as honey 5. the protection of water catchments.

Figure 1. (a) Box‐Ironbark forest (EVC 61) near Rushworth, dominated at this site by Eucalyptus tricarpa (Red Ironbark). (b) Similar forest in the Glenmona State Forest near Bendigo, consisting of E. tricarpa, E. leucoxylon (Yellow Gum), E. microcarpa (Grey Box) and E. goniocalyx (Long‐leaved Box). Both images taken October 2012.

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This manual is the fourth in a series which aims to describe the silvicultural management of Victoria’s main forest types within a broad ecological context, and provides the scientific and technical background on which current management practices are based. It is primarily designed for those who have responsibility for, or an interest in, the management of Box‐Ironbark forests for sustainable timber production. However, some of the silvicultural techniques (such as thinning described here can be also used for other important objectives, such as to improve animal habitat, or increase nectar production, with timber production being secondary. Thus, in addition to foresters, national park managers and rangers, teachers, environmental planners, apiarists, field naturalists and others should find this book valuable. Chapter 1 contains descriptive data about Box‐Ironbark forests such as tree species, distribution, growth, climate, history of forest use and timber production. Chapter 2 covers flora and fauna, soils, the influence of fire and other natural disturbances, and pests and diseases which may impact the forests. Chapter 3 describes the factors affecting the regeneration of the main tree species, such as flowering, seed production, the fate of seed, animal browsing impacts and stand growth. Chapter 4 discusses how silviculture can be adapted to meet different objectives. Chapters 5 and 6 detail silvicultural systems and practices appropriate for the Box‐Ironbark forests in Victoria, concentrating on the forests in central Victoria, also known as the Goldfields Bioregion. Wood production silviculture, which is the science and practice of managing forest harvesting, tree establishment and growth, is a critical part of sustainable forest management. Being based on scientific knowledge of how trees regenerate and grow, and their interaction with soils, fire and climate, and other species in the ecosystem, silviculture can be termed ‘applied ecology’. Definitions of technical terms are given in the Glossary (p. 121. An Index (page 131) will assist readers to find specific topics or references to certain species. 1.1.1 What are Box‐Ironbark forests? Box‐Ironbark forests are forests which include a number of distinctive eucalypt species in varying proportions with the common names of ‘Box’ and ‘Ironbark’ predominating (see Table 1). Different variants of this forest or woodland type also occur in central‐ western New South Wales (Sivertsen 1993).

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Table 1. The main eucalypt species found in Victorian Box‐Ironbark1 forests

Common species Less common species E. tricarpa Red Ironbark E. melliodora Yellow Box E. microcarpa Grey Box E. goniocalyx Long‐leaved Box E. leucoxylon ssp. Yellow Gum (or White E. macrorhyncha Red Stringybark pruinosa Ironbark) E. polyanthemos Red Box E. polyanthemos ssp. Red Box ssp. vestita marginalis and longior E. sideroxylon Mugga Ironbark E. albens White Box

State‐wide, there are 15 Ecological Vegetation Classes (EVCs)2, which include at least one of the character eucalypt species listed in Table 1, but the four significant EVCs are given in Table 2. Note ‐ only EVCs 61 and 20 are mapped in Figure 2, as the other EVCs are relatively very small. ‘Forests’ project an average crown cover of 30‐70%, while ‘woodlands’ project 10‐30% and both have a 15‐28 m mature height range. Both forests and woodlands may occur in stands or patches that are mainly even‐aged, but Box‐Ironbark stands are more often uneven‐aged due to past selective cutting. ‘State forests’ are public forests managed by the State government for many values, including timber production.

1.1.2 Area and distribution of Box‐Ironbark forests in Victoria Woodgate and Black (1988) estimated that 85% of the original Victorian Box/Stringybark/Ironbark area (about 3 million ha) had been totally cleared by 1987, leaving only about 454,000 ha across Victoria (ECC 1997).3 The clearing occurred mainly in the E. microcarpa, E. albens, E. melliodora and E. leucoxylon vegetation communities which grew on the more fertile soils that were attractive for farming.

1 The name ‘Box’ was applied by the early settlers of Australia who saw a resemblance between the hard, interlocked timber of the European Box (Buxus sempervirens) and that of Eucalyptus moluccana. The term ‘Box’ is further applied to describe the bark of many species ‐ that is, finely fibrous, often grey and tessellated, which after weathering exposes whitish patches. The name ‘Ironbark describes the hard, deeply fissured, kino‐impregnated bark of E. tricarpa and related species. 2 The Goldfields Bioregion contains most of the relevant EVCs. 3 In terms of Box‐Ironbark forests specifically. By 1993, about 30% of the 1 million ha of pre‐1750 Box‐Ironbark was still present (Table 13 in ECC 1997).

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Table 2. The main Ecological Vegetation Classes (EVCs) within the Box‐Ironbark forest type, with typical eucalypt species and localities across Victoria, in order of extent.

EVC No. EVC name & area Main eucalypt species4 Typical localities (approx.) (in order of approx. frequency) 61 Box‐Ironbark Forest tricarpa, microcarpa, Bendigo, Rushworth, Dunolly, 133,000 ha polyanthemos, sideroxylon Inglewood, Heathcote, (NE only), leucoxylon Puckapunyal, Maryborough, Castlemaine, St Arnaud, Chiltern‐Pilot area, Gippsland 20 Heathy Dry Forest macrorhyncha, Heathcote, Rushworth, N of 25,000 ha polyanthemos, tricarpa, Dunolly, S of Bendigo, goniocalyx Castlemaine, Pyrenees, Warby Ranges 22 Grassy Dry Forest macrorhyncha, NW of Dunolly, N of 5,000 ha polyanthemos, melliodora, Heathcote, Pyrenees, S of St goniocalyx Arnaud 48 Heathy Woodland leucoxylon, microcarpa, Dunolly, Stawell, SE & SW of 2,000 ha polyanthemos, tricarpa, St Arnaud goniocalyx

The main contiguous area of the Box‐Ironbark forests is the country between the Great Dividing Range and the Northern Plains (Figure 2). Outlying patches in western Victoria include the Werribee Gorge, Brisbane Ranges, Pyrete Ranges and the Aireys Inlet area (VNPA 2002, Costermans 2006). In the Stawell and Edenhope districts of western Victoria the Box‐Ironbark forest is predominantly E. leucoxylon (see Table 2). Eucalyptus sideroxylon is largely confined to forests and woodlands managed by Parks Victoria in north east Victoria, such as the Chiltern‐Pilot National Park, the Killawarra Forest and Warby Ranges in the Warby Ovens National Park (Figure 3). North east of Melbourne a small area of Box‐Ironbark occurs in the Christmas Hills. In Gippsland there are small occurrences of relatively pure E. tricarpa in the rain shadow area north of Heyfield, near Mt Taylor (north west of Bairnsdale), and at Mt Raymond (east of Orbost).

4 From EVC/Bioregion Benchmarks on the DEPI website (March 2014).

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Figure 2. Distribution of Box‐Ironbark forests in Victoria, showing EVC 61 – ‘Box Ironbark Forests’ and EVC 20 – ‘Heathy Dry Forest’. Areas of each EVC are listed in Table 2.

In lowland East Gippsland, where E. tricarpa occurs as a minor species in mixture with eucalypts such as E. globoidea, E, sieberi and E. botryoides (Featherston 1985), the forest type is normally termed ‘low elevation mixed species’ (LEMS) forests (see Murphy et al. 2013). This terminology should also be used where ‘box’ species such as E. polyanthemos ssp. longior, E. melliodora, E. albens, E. bosistoana (Gippsland Grey Box) and E. baueriana (Blue Box) grow in parts of Gippsland and north east Victoria. As at 2014, the net area of State forest in the Environment Conservation Council (ECC) Study Area was approximately 121,000 ha (ECC 2001), the majority of which (110,000 ha) is Box‐Ironbark in the Bendigo Forest Management Area (DSE 2008). The conservation area in the ECC Study Area, which includes national, state and regional parks, and Nature Conservation Reserves, is approximately 210,500 ha (ECC 2001). The small areas of Box‐Ironbark forest in central and East Gippsland and the Otway Range are estimated to total about 2,000 ha.

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Figure 3. (a) Mature Eucalyptus sideroxylon (Mugga Ironbark) growing to about 30m tall, and (b) one old‐growth Mugga over 2 m in diameter in the Killawarra Forest, Warby Ovens National Park (near Wangaratta in north east Victoria, May 2007).

1.2 General features of Box‐Ironbark forests 1.2.1 Species composition, density and size Based on 1,481 plots over six working circles, the Box‐Ironbark Timber Assessment (BITA) project (NRE 1998) found that E. tricarpa (30% of basal area) was most common, followed by E. microcarpa (24%) and E. macrorhyncha (14%), although these averages varied widely according to the particular working circle. Average basal area was 12.5 m2/ha. Table 3 shows stocking (tree stem density) averages by diameter class across the Box‐ Ironbark area in northern Victoria in the mid‐1990s, with the plots in the new parks and other reserves recommended in 2001 excluded. Average stocking ranged from 224 stems/ha (equivalent to an average square spacing of 6.7 m) in the St Arnaud area, to three times the density at 697 stems/ha (3.8 m spacing) in the Castlemaine working circle.

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Table 3. Stocking (stems/ha) by tree diameter class by working circle (ECC 2001, Table 17.4)

Working circle <20 cm 20.1 ‐ 40 cm 40.1 ‐ 60 cm >60 cm Total stems/ha St Arnaud 117 86 18 3 224 Inglewood ‐ Dunolly 207 85 13 0 305 Avoca ‐ Maryborough 582 82 13 1 678 Bendigo 451 65 9 0 525 Castlemaine 607 84 6 0 697 Rushworth ‐ Heathcote 300 100 12 0 412

Due to past utilisation history, trees larger than 60 cm diameter breast height over bark (DBHOB) are uncommon in most working circles (Table 3). In terms of height, the main species reach about 22 m at maturity on good sites and about 14 m on sites where soil and moisture are minimal. In terms of origin, 25% of the trees counted were estimated to be of seedling origin and 75% being of coppice origin, but this varied widely across the study area (NRE 1998). Note that all trees of coppice origin were at some stage in their life, of seedling origin (see section 3.1 for more detail on sources of regeneration and section 3.4.1 for more information on tree growth rates). 1.3 Climate The main area of Box‐Ironbark vegetation occurs predominantly within the 500 mm ‐ 700 mm average annual rainfall band, which runs along the lower slopes to the north of the Great Dividing Range (ECC 1997, VNPA 2002). In general, the climate is temperate; dry and warm to hot in summer (Dec‐Feb) and wetter and cooler in winter (Jun‐Aug). Rainfall (along with soil type) is a major factor in the occurrence of Box‐Ironbark forests and woodlands. Table 4 gives average monthly rainfall data for eight localities that are representative over the Box‐Ironbark forest distribution. The six‐month period May‐ October is usually the wettest (Table 4). Where the Box‐Ironbark type occurs south of the Great Divide, such as at Aireys Inlet and Heyfield, it is nearly always in a ‘rain shadow’ area. This is where ranges to the west induce rain to fall before it gets to the lower area to the east or south east, creating a dryer ‘rain shadow’ area. Droughts in the main Box‐Ironbark area occur approximately every one in five to ten years, and severe droughts can last for some years. Drought can have a major influence on the occurrence of many native plant and animal species (ECC 1997), as occurred in the 12 year period 1997‐2008, when rainfall was consistently lower than average. For example, in that period, Maryborough’s mean rainfall was 20% less than the 1961‐1990 average. Since 2008, however, the average annual rainfall has been about 10% above the long‐term average.

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Table 4. Mean monthly rainfall (mm) for the standard period 1961‐1990, for sites representative of Victorian Box‐Ironbark forest localities. Source: Bureau of Meteorology (BoM) website. ‘Ele’ is short for elevation.

Site and Ele Month Total (BoM no.) (m) J F M A M J J A S O N D Great Western 280 38 28 36 42 63 50 74 67 57 58 41 33 586 (79019) St Arnaud 240 34 25 31 40 58 49 58 62 51 54 35 30 526 (79040) Maryborough 249 38 33 33 45 59 48 58 65 54 59 39 38 568 (88043) Bendigo 225 37 26 36 48 60 52 63 70 58 56 35 40 582 (81003) Rushworth 170 44 26 37 47 59 48 55 60 54 49 38 37 553 (81043) Chiltern 209 44 31 38 54 73 61 85 87 71 70 49 48 711 (82010) Anakie 247 49 45 48 53 59 46 53 64 66 75 61 60 677 (87000) Glenmaggie 95 56 38 65 63 55 40 39 46 52 59 64 64 648 Weir (85034)

In terms of temperature, July is the coldest month and January and February are the warmest. In summer, very hot air is brought from the centre of Australia by north‐ westerly air streams, which can lead to maxima in excess of 35 OC for several consecutive days (ECC 1997). Mean temperatures in Bendigo range from 7.7 OC in winter to 21.8 OC in summer. Light frosts (≤2.0 OC) occur in the period May‐September and severe frosts (≤0.0 OC) occur almost exclusively in the three winter months (June, July and August) but the frequency varies widely from year to year. Hollows and valleys are the most frost‐prone landforms, with Castlemaine, for example, averaging 35‐40 severe frosts per year (ECC 1997). Bendigo, however, has on average six severe frosts per year, with a range of 1‐15 (BoM data). Table 4 shows that there is little variation in total rainfall (between 500 mm and 600 mm) for much of the north‐western area, but the north‐eastern extension of the Box‐Ironbark area (represented by Chiltern) is clearly wetter (on average), caused by higher winter and spring rainfall. The different species of Ironbark ‐ E. sideroxylon ‐

Box‐Ironbark Silviculture Reference Manual 9 found in this area could possibly be an historical ‘product’ of this higher rainfall. The rainfalls at Anakie (representing the Brisbane Ranges) and Glenmaggie Weir (Heyfield) which are south of the Great Dividing Range, fall between those in the north west and the north east. Other Bureau of Meteorology (BoM) data for the above sites show that the median monthly rainfalls are very similar to the mean figures.

1.4 Genetic factors There is relatively little known of the specific genetic make‐up and variability among the main eucalypts of the Box‐Ironbark forest type. Box‐Ironbark forests and woodlands are dominated by species in the Eucalyptus subgenus Symphyomyrtus (mainly ironbarks, boxes and gums). The other main subgenus, Monocalyptus (mainly peppermints, stringybarks and ashes) is represented by only one species ‐ E. macrorhyncha. One clear difference between these two groupings is that species in the Symphyomyrtus group are tolerant of the soil‐borne Phytophthora cinnamomi (Cinnamon Fungus) (Marks & Smith 1991). Tree genes are transmitted from one generation to the next through seed or forms of vegetative reproduction. The rate of natural selection for better adaptive traits depends on the diversity of available DNA, the length of the life cycle and the ratio of seeds to survivors (selection ratio). Most eucalypt species have an extremely high selection ratio. For example, thousands of seedlings per hectare (from perhaps hundreds of thousands of seeds per hectare) may germinate from seedfall after bushfires, but perhaps only about 100 trees per hectare will survive to reach reproductive maturity. In the case of the dominant Box‐Ironbark eucalypt species (Table 1), seedling establishment is uncommon for various reasons and the species mostly regenerate vegetatively ‐ by re‐sprouting (coppicing) from a cut stump or a burnt trunk. This system leads to little genetic variability and adaptation over (perhaps) centuries, in contrast to sexual reproduction which would result in improved adaptability in much less time. Due to changing environmental conditions (e.g. fire regimes, exotic pathogens, climate change, etc.) it is important that commercial regeneration procedures in Box‐Ironbark forests maximise potential adaptability. Boland (1978) examined the morphological variation of E. leucoxylon over 18 provenances in South Australia and Victoria. He studied seeds, leaves, fruit, glaucousness and the ontogeny of the seedling leaves, finding geographic trends in several characters which were presumed to be of adaptive significance. On the basis of this evidence he proposed four subspecies: petiolaris, megalocarpa, leucoxylon and pruinosa which were subsequently accepted (Boland et al. 2006). In E. tricarpa one feature known to vary within stands is the period of flowering, which is likely to be

10 Box‐Ironbark Silviculture Reference Manual genetically controlled. The majority of trees flower in winter (June‐August) but a significant minority flower in summer (December‐February), which is of great value to apiarists. Any collection of E. tricarpa seed for regeneration or reforestation works should be aware of this variation. There are about 21,700 ha of the summer‐flowering E. tricarpa within the Bendigo FMA, with 59% of the area located in parks/reserves and 39% in State forests. Interestingly, the majority of this area (77%) occurs in mixture with the more common winter‐flowering sub‐type (see section 3.2.1 regarding summer/winter flowering varieties). Seed collection and use, especially off‐site use, must take account of genetic factors in line with the requirements of the Code of Practice (DEPI 2014b) and Native Forest Silviculture Guideline No. 2 (Wallace 1994, see section 3.2.4 for more detail).

1.5 History of forest use and management Land use determinations by the Land Conservation Council (LCC 1978 & 1983) resulted in the designation of some State forests as parks and other types of reserves for biological, historic and recreation values. Following a later study and recommendations by the Environment Conservation Council (ECC 1997 & 2001), additional significant areas of State forest became national and regional parks where commercial uses, apart from bee‐keeping, were not permitted. 1.5.1 Pre‐settlement forests Early explorers of the region included Hume and Hovell (1824) and Major Mitchell (1836) whose notes provide some information about what the original forests looked like before European settlers started to make an impact on the land and the forests. Prior to the 1850s, the original Box‐Ironbark areas were thought to be mainly open woodlands with a low density (perhaps 30 stems/ha) of large trees, of E. tricarpa, E. microcarpa and E. leucoxylon, with diametres of 120‐150 cm (Newman 1961). However, Hateley (2010) presents evidence which shows that relatively dense forests of Box‐Ironbark existed before settlement. He quotes notes and diaries of early explorers and settlers as well as paintings by colonial artists. The Box‐Ironbark forests provided food and materials for the indigenous people who inhabited the land for many thousands of years before white man arrived. Aboriginal tribes often made shields, spears, canoes, boomerangs and bark shelters from ironbark trees (ECC 1997). The nectar‐rich ironbark flowers were soaked in water to make a sweet drink called yeerip korr (Slijkerman 2007).

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1.5.2 The mining industry The ‘Gold Rush’ which began in 1851 brought thousands of miners into the Box‐ Ironbark forests and woodlands. Forest clearing began in earnest in the 1860s after the alluvial surface gold was largely gone and deep mines were established, generating huge demands for timber (Groch 2006). Such activity has had a major impact on surface soil conditions and fertility (Dexter 1960). Around the major mining centres such as Bendigo and Castlemaine, the forests were clear‐felled for timber to feed boilers of steam engines and line mine shafts (Hooper 1992, Figure 4). In those areas not turned over to agriculture (the more fertile sites), the original forest was replaced by a dense coppice regrowth forest (Kellas 1991).

Figure 4. A Box‐Ironbark forest cleared for gold mining at Sailors Gully, Bendigo. Painting in 1853 by W. H. Walter. Image courtesy of the National Museum, Australia.

1.5.3 The agricultural industry Following the enthusiastic reports of the land in the colony of Victoria by explorers such as Major Mitchell, early settlers and squatters quickly introduced large numbers of sheep and cattle, and by 1849, squatting runs occupied most of the Box‐Ironbark region (ECC 1997). In the period from the 1850s to the 1870s large areas were ‘thrown open’ for farming and, if not already cleared during the Gold Rush, were cleared of most vegetation by ring‐barking, then pushing over and burning the dead trees. Efforts were made to retain some Box‐Ironbark forests as State forest (e.g. Ligar 1865 in Kellas

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1991), but most of the better quality land was cleared for grazing and later, for cropping (ECC 1997). By the 1930s, significant parts of the forests were fenced off for sheep grazing leases (Newman 1961). In the late 1970s, 27% of public land in the north central study area was still subject to annual grazing licences or agistment, mainly for sheep (LCC 1978). The combined result of clearing for mining and agriculture was that by 1993, the Box‐ Ironbark/Stringybark forests and woodlands covered only about 454,000 ha or about 15% of its estimated pre‐European extent (ECC 1997). 1.5.4 The timber industry Because of the Gold Rush, timber from the Box‐Ironbark forests, apart from being used for firewood for domestic heating and cooking, was in great demand for support structures in mines, fuel for steam boilers, water races, house construction, fences, sleepers for the railways and poles for the telegraph system (ECC 1997). Ferguson (1871, in Kellas 1991) reported that most of the Box‐Ironbark forests were devoid of useful timber following ‘wanton destruction’. In 1889, regulations were introduced requiring that timber could only be cut from trees marked and branded by a Forest Officer, and that debris resulting from timber harvesting be slashed and burned (Newman 1961, Figure 5). By 1900, in many areas, coppiced trees were in their third period of regrowth due to regular cutting to supply the needs of the mining industry (Newman 1961). Rapid development of railways throughout Victoria in the 1870‐1910 period resulted in a huge demand for the durable timbers of E. tricarpa, E. microcarpa and E. camaldulensis (River Red Gum) for sleepers. For example, from 1896‐1900, an average of 50,000 sleepers were cut each year from forests between Rushworth and Heathcote (Slijkerman 2007) leading to the Conservator of State Forests (George Perrin) advocating the exclusion of sleeper hewers from the Box‐Ironbark forests as they used potential sawlog quality trees, thus depriving sawmillers of a resource (Perrin 1890 in Kellas 1991). The durable Box and Ironbark species in East Gippsland, such as E. tricarpa, E. bosistoana and E. polyanthemos were also in strong demand for heavy construction as well as railway sleepers. By 1920, about 60% of Victoria’s hewn beams and 25% of the sleepers were being produced from the coastal and foothill forests east of Nowa Nowa (McKinty 1969). Bridge construction for both railways and roads drew on the prized strength and durability of the timber of the Box and Ironbark species (Chambers 2006).

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Following a Royal Commission on State Forests and Timber Reserves (Anon 1901 in Kellas 1991), increased controls were introduced on harvesting and thinning operations. By 1917 over 8,000 ha of Box‐Ironbark and Red Gum regrowth forests had been thinned (Mackay 1917 in Kellas 1991, Figure 6). With the establishment of the Forests Commission in 1919, utilisation was better controlled and commercially valuable forests were reserved for wood production (ECC 1997).

Figure 5. Burning slash during 1928 following harvesting of a Box‐Ironbark forest in the Wellsford State Forest.

From about 1912 to the 1970s, timber poles (8‐12 m long) were harvested from the Box‐Ironbark forests for electricity and telephone lines, as well as for farm sheds, although production declined from around 1930 due to shortages of suitable trees (Newman 1961, Slijkerman 2007). The economic depression of the 1930s saw large work gangs of otherwise unemployed men carry out thinning and ‘improvement’ works in the forests (Newman 1961). For this purpose men were housed in bush camps near towns such as Bealiba, Castlemaine, Chiltern and Rushworth. Improvement works, such as ‘regeneration fellings’ or ‘liberation treatment’ mainly involved felling or sap‐ringing large, old trees which had little timber value (apart from firewood) (Newman 1961). However, in this process, hollows, which are important for many birds and mammals, were severely reduced (Traill 1993).

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During World War II a large amount of thinning in the Box‐Ironbark forest (for firewood sent to Melbourne and charcoal manufacture) was undertaken by prisoners of war and internees who were also based in camps located in the forests (Newman 1961). During the 1950‐1980 period, apart from firewood, the main focus of the local timber industry became production of posts, strainers, sleepers, shed poles and round rails for horse and cattle yards. Following that period, demand significantly decreased for round timbers due to the increased availability of treated pine. Thinning for firewood by government crews and private contractors treated approximately 1,000 hectares per year in the 1980s (Kellas 1991). Such silvicultural Figure 6. Thinning of Box‐Ironbark in work resulted in the structure of the forest Wellsford State Forest during 1914, being of two main age/size classes, with showing the results 10 years later in 1924. larger, better formed trees being an ‘overwood’ to smaller, coppice regrowth. In the 1990s, firewood constituted over 80% by volume of the licensed timber output from public forests in the Box‐Ironbark forest type, and totalled over 32,000 m3 in the Bendigo Forest Management Area (FMA) in 1994/95 (ECC 1997). 1.5.5 The eucalyptus oil industry Within certain Box‐Ironbark forests there are scattered isolated patches of ‘mallee’ eucalypts. By the early 1900s, most of these had been cut down and converted into low coppice stands and managed for eucalypt oil production (Figure 7). The leaves of Eucalyptus polybractea (Blue Mallee), having a cineole oil content of about 80%, was the most sought‐after species, and now constitutes most of the remaining area of mallee‐type forest under oil production, which now totals about 2,230 ha. E. viridis (Green Mallee), E. behriana (Bull Mallee) and E. tricarpa are also harvested in small quantities where these species grow as minor components in mixture with E. polybractea.

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The early oil distilleries in the Bendigo and Rushworth areas began operating in the 1870s (Groch 2006). Prior to 1950, Australia was the leading supplier of all types of eucalypt oil to the world, with about 150 tonnes produced annually in Victoria in the early 1930s (Newman 1961). However, largely due to cheaper production from eucalypt plantations in countries such as China and Swaziland, the local industry gradually declined. Wrigley and Fagg (2010) have summarised the history and current state of the industry. In the 1970s, Victoria’s annual oil production averaged about 40 tonnes (from 20 distillers) from about 3,500 ha harvested (Ritchie 1977), but had declined by the 1990s to just 25 tonnes (ECC 1997).

Figure 7. Eucalyptus oil distillery operating at a School of Forestry camp during 1928 in the Wellsford State forest.

Recommendations of the Environment Conservation Council (ECC) in 2001 saw significant areas of State forest change tenure to conservation reserves where oil production was excluded. Current average annual eucalyptus oil production is now 10‐ 12 tonnes from only five licences held in Victoria’s State forests (P. Bates, DEPI, pers. comm.). 1.5.6 The charcoal industry Ceasing in the 1950s, charcoal production was another minor, but temporarily very important, forest industry in the Box‐Ironbark forests. It was produced by slowly burning dry, dense wood (such as E. tricarpa, E. polyanthemos and E. microcarpa) in reduced oxygen conditions (such as pits and kilns). Charcoal production was highest

16 Box‐Ironbark Silviculture Reference Manual during World War II when petrol shortages led to the use of ‘producer gas’ as an alternative fuel, with kilns operated by the Forests Commission located at Dunolly, Ballarat and Bendigo (ECC 1997). This industry generally used low grade logs and offcuts from sleeper cutting. 1.5.7 The apiary (bee‐keeping) industry Honey Bees (Apis mellifera) (Figure 8) were introduced to Australia in 1822. They quickly colonised native forest and woodland areas which have plenty of nectar and pollen‐producing plants. Commercial bee‐keepers were well established in the Box‐ Ironbark area prior to 1900 (Briggs 1993).

Figure 8. A Honey Bee (Apis mellifera) working flowers of E. polyanthemos (Red Box) in a Box‐ Ironbark forest near Chiltern, north east Victoria. Note the open and clumped nectaries which, although individually small in this species, assist efficient feeding by Honey Bees and other nectarivores. Several of the common eucalypt species in the area (see Table 1) have either excellent nectar yield and quality, or good pollen, or both (see Table 4 in Dooley 2004). These include four of the top five nectar producing species in Victoria ‐ E. microcarpa, E. leucoxylon, E. tricarpa and E. melliodora (Goodman 2001). The latter species is the most sought‐after species and has been excluded from timber harvesting since the early 1980s. It is not a surprise then that, at least in the early 2000s, the large majority (nearly 40%) of the permanent apiary sites in Victoria were located within the Bendigo FMA (Dooley 2004). Other Box‐Ironbark localities in Victoria are also targeted by bee‐ keepers.

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In 1994/95, public land in the Bendigo FMA produced approximately 1,750 tonnes of honey and 50 tonnes of beeswax (ECC 1997). Apiarists also sell pollen and queen bees, and are paid by orchardists to provide hives to enhance pollination of fruit trees (ECC 1997). In the mid‐1990s it was estimated that about 70% of Victoria’s honey and beeswax production came from the Box‐Ironbark forests in northern Victoria (ECC 1997), making apiculture a significant forest‐based industry in the region. State‐wide in 2011/12, over 5,000 licences were issued for over 3,600 bee sites covering a range of forest types (DEPI 2014a). In the Bendigo FMA in 2013 there were 359 bee sites in reserves managed by Parks Victoria (with 26 in summer‐flowering E. tricarpa) and 303 sites in State forests (with 18 in summer‐flowering E. tricarpa) (2013 DSE report provided by M. Camilleri, DEPI, Epsom). 1.6 Current timber production Sawlog production in recent decades has fluctuated, depending on availability and markets for the sawn timber, and the area of forest that was suitable and available for timber production.The most recent land use determination (ECC 2001) resulted in a major reduction of State forest, from 48% of public land to 28%. Accordingly, both sawn timber and firewood outputs have declined significantly in the last 15 years. About 72,000 ha are suitable and potentially available for sawlog production in the Bendigo FMA (Forest Solutions 2013). Currently, the licenced annual volumes (allocated after a tender system) in the Bendigo FMA are 360 m3 for Grade 1 sawlogs, and 2,000 m3 for Grade 2 sawlogs which are well within the calculated annual sustainable harvest levels (Forest Solutions 2013). These logs are sawn at sawmills in Talbot and Rushworth (Figure 9a). Most of the sawn timber is kiln‐dried and subsequently used for a variety of value‐ added purposes, including furniture, flooring and window frames. Offcuts are sold for firewood. The main species sought and harvested are E. tricarpa, E. microcarpa, E. leucoxylon and E. cladocalyx, which are strong and durable timbers, and E. tricarpa, which also has an attractive, deep red colour (Figure 9b). A demand exists for domestic and commercial firewood, especially in the Bendigo, Maryborough, Rushworth and Castlemaine districts. In the Bendigo FMA, commercial firewood licences totalled 3,000 m3 in 2014. Many firewood contractors sell their firewood to Melbourne customers. For domestic use, firewood can be collected without licence or payment by people in regional locations, within designated areas of State forest. As no trees are allowed to be

18 Box‐Ironbark Silviculture Reference Manual felled for this firewood, all wood collected must already be on the ground. This resource, estimated at 15,000 m3 per year, derives mainly from thinning or low quality wood left after sawlog extraction.

Figure 9. (a) A Lucas Sawmill at T. W. Jones Hewn and Sawn Ironbark Timbers, Rushworth, with logs of E. tricarpa and E. microcarpa waiting processing. (b) Ted Jones shows off the appealing colour of Red Ironbark timber in posts cut to accommodate fencing rails (image (b) from Forest Solutions et al. 2013).

1.7 Silvicultural research and development in Box‐Ironbark Forests Commission staff, including Karl Ferguson, undertook some basic regeneration experiments in the 1930s. Of interest to silviculture are the long‐term eucalypt flowering and budding reports undertaken by Forests Commission staff from as early as 1933 until 1978. These had a clear apiarist/honey production purpose at the time, however, these data are now considered valuable for understanding seed production as well. Marie Keatley and Irene Hudson utilised some of this data 30 years later. In the late 1950s, Zimmer and Ron Grose, amongst others, carried out early laboratory studies on seed germination and root systems of some Box‐Ironbark eucalypt species, and Leon Pederick elucidated the biology of, and examined control techniques for, Cassytha melantha (Coarse Dodder‐laurel). In the same period, Barrie Dexter studied

Box‐Ironbark Silviculture Reference Manual 19 seed supply and field germination in the natural regeneration of E. tricarpa in the Rushworth area. Systematic research commenced in the early 1970s with the establishment of the Forests Commission’s Research Station at Creswick. Research foresters such as Ross Squire and John Kellas conducted silvicultural studies mainly in the Heathcote and Bendigo districts, focusing on growth following release from competition, thinning and Dodder‐laurel control. In the period 1993 to about 2001, the Box‐Ironbark and Red Gum Research and Development Action Group (BIRGDAG) performed a key role in the important dissemination of Box‐Ironbark‐related research and its incorporation into silvicultural practices (as described in Fagg 2003). This Departmental group brought together researchers, field staff and policy staff to discuss and resolve forest management issues. It was established following a three day workshop on the silviculture of Box‐Ironbark forests, conducted largely by lecturing staff Brian Fry and Ron Hateley from the Victorian School of Forestry and Land Management (Figure 10).

Figure 10. A group of researchers, field staff and policy staff (Department of Conservation and Natural Resources) at a three day workshop on the silviculture of Box‐Ironbark forests in 1992, led by Ron Hateley and Brian Fry from the Victorian School of Forestry and Land Management.

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Also in that decade, a multi‐disciplinary program of biodiversity research was conducted in Box‐Ironbark forests by the Arthur Rylah Institute (DSE) and collaborating institutions (especially Deakin, Monash and La Trobe Universities, and the Museum of Victoria). The program focused on the effects of ecosystem processes and disturbances, including forest fragmentation, with Ralph Mac Nally, Andrew Bennett, Todd Soderquist, Richard Loyn and Geoff Brown making substantial contributions. Vertebrate fauna were the main subjects of interest, but the program also included work on vegetation and invertebrates, headed by Annette Muir, Charles Silveira and Ralph Mac Nally. In the 2000s, fire ecology was the subject of further studies by Arn Tolsma, Andrew Bennett and others. In the mid‐2000s, Corinna Orscheg studied the germination requirements of E. tricarpa, the effects of stem density on seed characters and factors affecting field germination. Also in that decade, PhD studies by Marie Keatley and Jenny Wilson examined the flowering patterns/phenology of the main eucalypt species, and Parks Victoria (Patrick Pigott) coordinated a large field trial which aimed to evaluate ecological thinning. In summary, despite the research work listed above, the quantity of documented silvicultural research in the Box‐Ironbark forest type has been limited compared with that undertaken in other forest types, for example mixed eucalypt species (e.g. Murphy et al. 2013), mainly due to the higher value commercial yields of timber in these types. For detailed information regarding many of the above studies, refer to Chapter 3.

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2. Ecology 2.1 Aspects of the Box‐Ironbark ecosystem Box‐Iron bark forests have a high level of diversity largely because of the position of the ecosystem in the landscape. They are located between the semi‐arid environments to the north and west, and moister environments to the east and south. In addition, geology/soil types and topography play major roles in the type and composition of the vegetation communities, which result in a great variety of habitats for wildlife (Tzaros 2005). The following account focuses mainly on the four core EVCs as listed in Table 1. 2.1.1 Flora In the main Box‐Ironbark area to the north of the Great Dividing Range, Muir et al. (1995) identified about 1,000 native vascular plant taxa, 70 of which are rare or threatened in Victoria. Apart from the eucalypt species, many understorey species are distinctive, not being common in other regions of Victoria. These forests are also rich in terrestrial orchids (Figure 11), with a large proportion of Victorian species represented. A selection of shrub and herb species within the four main EVCs is listed in Table 5.

Figure 11. (a‐b) Flowering Acacia pycnantha (Golden Wattle) near Yandoit, and (c) Caleana major (Flying Duck Orchid) is an iconic terrestrial orchid species found in Box‐Ironbark forests.

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Table 5. Brief description of the flora of the main EVCs within the Box‐Ironbark forest type

EVC name & Description Main Some typical understorey species no. Eucalyptus (covering a range of life forms) species Box‐Ironbark Occurs on low hills on tricarpa Acacia pycnantha Golden Wattle Forest in fertile often stony microcarpa Acacia genistifolia Spreading Wattle Acacia acinacea Gold‐dust Wattle (61) soils. Open eucalypt polyanthemos Cassinia arcuata Drooping Cassinia overstorey to 20 m. leucoxylon Pultenaea largiflorens Twiggy Bush‐pea Mid‐storey is a dense sideroxylon Astroloma humifusum Cranberry Heath to open shrub layer (latter NE only) Senecio tenuiflorus Slender Fireweed over an open ground Gonocarpus tetragynus Common Raspwort layer of herbs and Joycea pallida Silvertop Wallaby‐grass grasses Thysanotus patersonii Twining Fringe‐lily Heathy Dry Occurs in shallow, macrorhyncha Brachyloma daphnoides Daphne Heath Forest skeletal soils on a polyanthemos Acacia pycnantha Golden Wattle Cassinia arcuata Drooping Cassinia (20) range of land forms. tricarpa Hovea heterophylla Common Hovea Open eucalypt goniocalyx Acrotriche serrulata Honey Pots overstorey. Xerochrysum viscosum Shiny Everlasting Understorey is a low, Opercularia varia Variable Stinkweed often sparse layer of Austrostipa mollis Supple Spear‐grass ericoid shrubs Lomandra filiformis Wattle Mat‐rush including heaths and Dianella revoluta Black‐anther Flax‐lily peas Grassy Dry Occurs on a variety of macrorhyncha Acacia paradoxa Hedge Wattle Forest slopes and soil types. polyanthemos Daviesia ulicifolia Gorse Bitter‐pea Pimelea humilis Common Rice‐flower (22) Open eucalypt melliodora Wahlenbergia stricta Tall Bluebell overstorey to 20 m, goniocalyx Geranium solanderi Austral Cranesbill with a mid‐storey layer Hydocotyle laxiflora Stinking Pennywort of Acacia spp, with a Lomandra filiformis Wattle Mat‐rush sparse understorey. Poa sieberiana Grey Tussock‐grass Diverse ground cover Amyema miquelii Box Mistletoe of grasses, herbs and Hardenbergia violacea Purple Coral‐pea sometimes ferns. Heathy Generally associated leucoxylon Acacia pycnantha Golden Wattle woodland with nutrient‐poor microcarpa Grevillea alpina Cat’s Claw Grevillea Astroloma conostephioides Flame Heath (48) soils. Low (to 10 m) polyanthemos Hibbertia riparia Erect Guinea‐Flower eucalypt woodland tricarpa Senecio tenuiflorus Slender Fireweed with a diverse array of goniocalyx Leptorhynchos tenuifolius Wiry Buttons narrow‐leaved shrubs. Gonocarpus tetragynus Common Raspwort Ground cover is Joycea pallida Silvertop Wallaby‐grass normally fairly sparse. Dianella revoluta Black‐anther Flax‐lily Cassytha glabella Slender Dodder‐laurel

In addition, over 300 ‘environmental weed’ species were identified across their 494 quadrats, of which 10 species were deemed to be ‘locally highly invasive’.

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Semi‐parasitic mistletoes (Amyema pendula (Drooping Mistletoe) and A. miquelii (Box Mistletoe)) are quite common throughout the Box‐Ironbark area, reaching high frequency in places. It is an important source of food (fruit and nectar) for a number of native bird species, such as the Mistletoebird and the rare Painted Honeyeater (which feed on the drupes), numerous honeyeaters (which feed on nectar) and also insects, such as the Imperial White Butterfly (which also take nectar as adults while the larvae feed on mistletoe foliage) (VNPA 2002, Watson 2001). 2.1.2 Fauna A total of 287 species of native wildlife (mammals, birds, reptiles and frogs5) have been recorded in the Box‐Ironbark ecosystem in Victoria (Tzaros 2005).The fauna of the Box‐ Ironbark can be grouped into 4 major groups based on their broader distributions in Australia (ECC 1997): 1. Eyrean species (predominantly inland) reaching the edge of their range (e.g. Budgerigar, Rainbow Bee‐eater and Gould’s Sand Goanna) 2. Bassian species (predominantly mountain or coastal) reaching the inland limit of their range (e.g. Sugar Glider, Crimson Rosella, and Powerful Owl) 3. ‘Box‐Ironbark stronghold’ species (e.g. Brush‐tailed Phascogale, Bush Stone‐ curlew, Swift Parrot, Grey‐crowned Babbler and Fuscous Honeyeater, Regent Honeyeater) 4. Widespread species (occurring in a range of other habitats) (e.g. Echidna, Willie Wagtail, and Australian Magpie). Nesting or roosting hollows play a key role in Box‐Ironbark ecosystems, with 25% of resident mammal, bird and reptilespecies requiring such hollows in trees or old stumps (ECC 1997). A major survey in the mid‐1990s revealed an average of 26 hollows per hectare across the main Box‐Ironbark area in northern Victoria (NRE 1998). The majority of these hollows were observed in box eucalypts, especially E. microcarpa and E. polyanthemos. Most hollows were in large trees (Soderquist 1999), although this may have been partly because of their age, and there is evidence that supple small trees may be prone to the shearing stresses that lead to subsequent hollow formation (L. Vearing, DSE, pers. comm.). Another feature of Box‐Ironbark areas is the prominence of high nectar‐producing eucalypts, which, when flowering attract concentrations of animals (nocturnal and diurnal) to feed on the nectar and on other animals that are attracted to the area (ECC 1997).

5 For scientific names of wildlife in this manual, refer to Menkhorst (1995) for mammals, Christidis and Boles (2008) for birds, Cogger (2014) for reptiles and Barker et al. (1995) for frogs.

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Mammals A total of 38 species of native mammals can be found in the Box‐Ironbark areas. Of these, 18 are marsupials such as the relatively common Eastern Grey Kangaroo (which is common and conspicuous), the Black Wallaby (which has increased in recent years), the Common Brushtail Possum and the Sugar Glider. The largest group of placental mammals are the insectivorous bats. Many of the 13 species are widespread and common. Being nocturnal, these bats shelter in tree hollows and under bark during the day and fly often up to 10 km at night seeking food (Tzaros 2005). The Victorian distribution of the Brush‐tailed Phascogale, Squirrel Glider, and Yellow‐ footed Antechinus (often termed ‘woodland specialists’) is centred on Box‐Ironbark habitats. Brush‐tailed Phascogales are classed as ‘vulnerable’ in Victoria, and Squirrel Gliders as ‘endangered’ (DSE 2013). Yellow‐footed Antechinus are widespread in Box‐Ironbark forests and also in forests of E. camaldulensis (River Red Gum) (Menkhorst 1995). In Box‐Ironbark forests they favour stands with abundant leaf litter and numerous hollow‐bearing trees or rocks (Kelly & Bennett 2008). They forage for arthropods from dry open ground, and from the trunks and branches of the eucalypt trees (often in daylight). They breed in winter and males die soon after mating. The Brush‐tailed Phascogale (Figure 12) is found mainly in Box‐Ironbark woodlands and associated stringybark forests where the understorey and ground cover often consist of only scattered tussocks and forest litter. They are often reported on roadsides with remnant trees and wooded farmland (Menkhorst 1995). A monitoring program showed that numbers declined during the 2000s (Holland et al. 2012) when dry conditions prevailed. Preferred hollows in trees are characterised by entrances of less than 30‐40 mm in diameter, with entrance heights up to 11 m (Soderquist 1993), but rotted out stumps left by timber‐getting are Figure 12. Brush‐tailed Phascogale on also often used (Menkhorst 1995). an E. polyanthemos in the Reef Hills State Park, 2003. The Brush‐tailed Phascogale forages for arthropods mainly on the trunks of trees and amongst ground litter, but will also feed on nectar produced in eucalypt flowers. Like

Box‐Ironbark Silviculture Reference Manual 25 the Antechinus, males of about one year old die after mating in winter (Menkhorst 1995). The Squirrel Glider is much less widespread than the Brush‐tailed Phascogale and prefers habitats such as remnant mature or mixed‐age stands of more than one eucalypt species, or E. camaldulensis forest (Menkhorst 1995). Roadside stands are sometimes used and forests with scattered wattles are favoured (Silveira et al 1997). Mixed eucalypt species invariably include gum‐barked and high nectar‐producing species, including some which flower in winter. In terms of ironbark eucalypts it appears to be restricted to E. sideroxylon, being uncommon in E. tricarpa stands (Menkhorst 1995). Birds Over 180 species of native birds have been recorded in the Box‐Ironbark forest and woodlands. Of these birds, most (~85%) breed in the area, whilst many others are regular migrants (Tzaros 2005). This is a greater diversity than in mixed‐species foothill forests, reflecting the mixture of species from wet and dry environments. Box‐Ironbark eucalypts often flower profusely in winter, attracting large influxes of nectarivores6, such as honeyeaters (mainly from the wetter forests in nearby hills), along with blossom‐feeding parrots, such as lorikeets and Swift Parrots. Carbohydrate‐ rich nectar is the main attraction but the lorikeets also rely on pollen as a source of protein, and the honeyeaters take insects for the same reason. Lerps and honeydew produced by psyllid insect larvae on the eucalypt foliage sometimes offer a similar resource. Favoured tree species include E. sideroxylon, E. tricarpa, E. leucoxylon and E. albens, along with mistletoes (Amyema spp.). These mass flowering events tend to be patchy in space and time, and stronger in mature stands of big trees than in regrowth (Wilson & Bennett 1999). Box‐Ironbark forests also attract high numbers of insectivorous7 birds that feed from open ground below tree cover. This group of birds forage from woody and leafy debris among a patchy scrub and herb understorey, and some nest in these situations (e.g. Bush Stone‐curlew and Painted Button‐quail). These birds and nectarivores are well represented in Box‐Ironbark forests compared with most other forest types (Loyn 1985, Silveira et al. 1997, Tzaros 2005). Granivores8, and insectivores that feed from the canopy or bark form similar proportions of the bird

6 ‘Nectarivores’ ‐ feed on nectar from flowers 7 ‘Insectivores’ ‐ feed on insects 8 ‘Granivores’ ‐ feed on seeds

26 Box‐Ironbark Silviculture Reference Manual community as in other forest types, whereas frugivores9 and insectivores that forage from shrubs or shady ground are scarce. The main frugivores are those that feed on mistletoe fruits such as the Mistletoebird and Painted Honeyeater. Hollow‐nesting birds are well represented (15% of species or ~20% of the bird community in terms of relative abundance), but less so than in E. camaldulensis forest where they may constitute >30% of the bird community (Loyn 1985). Species such as the Laughing Kookaburra and Powerful Owl require large hollows, while smaller birds such as treecreepers and the Striated Pardalote require much smaller spouts and hollows. Two resident honeyeater species, Fuscous Honeyeater and Yellow‐tufted Honeyeater(Figure 13), often coexist in Box‐Ironbark forests, forming high proportions of the bird community while other species are less numerous or arrive and depart as the eucalypts flower (Loyn 1985, Silveira et al 1997). Common insectivores include some that feed in the canopy, such as the Weebill and Striated Pardalote, from bark, such as the Brown Treecreeper (Figure 13), or from open ground among trees, such as the Scarlet Robin and Buff‐rumped Thornbill.

Figure 13. (a) The Yellow‐tufted Honeyeater is a resident of Box‐Ironbark forests, as is the insectivorous Brown Treecreeper (b).

9 ‘Frugivores’ – feed on fruit.

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Box‐Ironbark forests provide the main Victorian habitat for the following 15 bird species: Bush Stone‐curlew, Little Lorikeet, Swift Parrot, Turquoise Parrot, Barking Owl, Speckled Warbler, Yellow‐tufted Honeyeater, Fuscous Honeyeater, Regent Honeyeater, Black‐ chinned Honeyeater, Painted Honeyeater Grey‐crowned Babbler, Restless Flycatcher, White‐bellied Cuckoo‐shrike and Diamond Firetail (Loyn 1985, Emison et al 1987, Silveira et al. 1997). The forests also provide important habitat for many more widespread birds of dry forests, such as the Musk Lorikeet, Brown Treecreeper, Hooded Robin and Jacky Winter, and for some scarce species that occupy additional habitats, for example, the Malleefowl, Square‐tailed Kite, Superb Parrot, Powerful Owl, Crested Bellbird, Gilbert’s Whistler and Chestnut‐rumped Heathwren. Conservation status Nationally, of these species, Swift Parrots and Regent Honeyeaters are classed as ‘endangered’ and Malleefowl are classed as ‘vulnerable’ (SEWPAC 2014). Within Victoria, the conservation status of the following species is listed in DSE (2013) as: 1. Critically Endangered: Regent Honeyeater 2. Endangered: Barking Owl, Bush Stone‐curlew, Malleefowl, Superb Parrot, Swift Parrot and Grey‐crowned Babbler 3. Vulnerable: Painted Honeyeater, Speckled Warbler and Chestnut‐rumped Heathwren. Many species have suffered declines associated with the loss and fragmentation of habitat after agricultural clearing (Mac Nally et al. 2000). More recent declines were associated with prolonged drought (Mac Nally et al. 2009) and competition from aggressive native Noisy Miners in fragmented systems (Grey et al. 1997, Mac Nally et al. 2000, Maron et al. 2013). Substantial recent declines and range contractions have been noticed for several species including the Regent Honeyeater, Crested Bellbird and Gilbert’s Whistler, while Turquoise Parrots and Grey‐crowned Babblers appear to have responded positively to conservation efforts in some areas. Bird migration About a third of the land‐bird species undertake regular seasonal migrations. Summer visitors generally arrive between August and October (December‐January for swifts) and leave in March or April, while winter visitors are present from March or April to spring (Tzaros 2005). The two species of swifts that are summer migrants from breeding

28 Box‐Ironbark Silviculture Reference Manual sites in north east Asia include the White‐throated Needletail and (less regularly) the Fork‐tailed Swift (Emison et al. 1987). Altogether around 40 of the 180 land‐bird species are mainly summer visitors, migrating from within Australia or nearby islands, and most of them breed locally. Swift Parrots visit the region in winter and spring from breeding sites in Tasmania, and 15 other land‐ bird species are mainly winter visitors from wetter forests in the Great Dividing Range where they breed. Some of them have established small breeding populations within the region (e.g. Gang‐gang Cockatoo, Golden Whistler and Pied Currawong). Several honeyeaters are in this group of mainly winter visitors (e.g. Yellow‐faced Honeyeater, White‐naped Honeyeater and Eastern Spinebill). Swift Parrots often move between sequentially flowering stands of eucalypts within a winter season, and select different stands of Box‐Ironbark forest in different years, depending on the availability of nectar (Mac Nally & Horrocks 2000). Reptiles and Amphibians Reptiles are well represented in the Box‐Ironbark ecosystem, with 41 species covering nine families: Tortoises (1 species), geckoes (3), legless lizards (4), skinks (18), dragons (2), goannas (2), blind snakes (3), pythons (1) and elapid snakes (7). The skinks range from the very small Grey’s Skink, Large‐striped Skink and Garden Skink to the larger Stumpy‐tailed Lizard and Common Blue‐tongued Lizard. Most species are confined to the ground, foraging and basking on the ground and on rocks, and sheltering under debris on the ground (Tzaros 2005). The Carpet Python, a non‐venomous snake, is the only species of python in Victoria, just occurring in a few isolated rocky outcrops. Venomous snakes such as the Eastern Brown Snake and the Red‐bellied Black Snake are widespread. Reptiles such as the Woodland Blind Snake, Tree Goanna and Tree Dragon are ‘woodland specialists’, being commonly associated with Box‐Ironbark habitats or similar dry forest throughout Victoria. Some reptile species are listed as threatened in Victoria (DSE 2013). These include the Millewa Skink (critically endangered), Carpet Python, Lace Monitor and Pink‐tailed Worm‐Lizard (endangered), and Bandy Bandy and Bearded Dragon (vulnerable). Despite their overall diversity, reptiles are not particularly numerous in Box‐Ironbark forests, especially where understorey has been disturbed (Brown 2001). Species composition was found to vary with forest fragmentation. The two most abundant species in extensive forest (Tree Dragon and White’s Skink) were very rare in fragmented forest patches, whereas the most common species in fragmented patches

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(Boulenger’s Skink) was significantly less common in extensive forest (Mac Nally and Brown 2000). About 15 species of frogs are known to occur in the region, including the Common Froglet, Growling Grass Frog and the Eastern Banjo Frog (Tzaros 2005). They generally occur at moister sites such as dams, waterholes, creeks and gullies and are not confined to Box‐Ironbark areas, being widespread in south east Australia. Invertebrates Insects and other invertebrates, such as worms, including microbes are essential components of all strata of Box‐Ironbark forest. Their presence is a pre‐requisite for: (1) ‘foliage‐turnover’ ‐ particularly species of Coleoptera (beetle larvae and adults), Lepidoptera (larvae of moths, butterflies) and Hymenoptera (sawfly larvae) which are all leaf‐feeding insects (2) breakdown of dead organic matter and thus proper hygiene on the forest floor (3) soil aeration and return of nutrients to the soil. They also contribute to forest food chains and biological control of co‐existing invertebrates and plants through foliage‐feeding, predation and parasitism. Moreover, various airborne insects of Hymenoptera (especially bees) and Lepidoptera are important in effecting cross‐pollination, and hence seed formation among eucalypts and other flowering plants. Australian termites comprise at least 348 species with some still undescribed. All species form an integral part of the invertebrate fauna in eucalypt forests. The wood of most eucalypts in Box‐Ironbark forest, for example E. leucoxylon, E. polyanthemos and E. sideroxylon, is inherently resistant to termite attack on account of its great strength, interlocked grain, high density and resistance to fungal decay. Consequently, the subterranean and/or mound‐building termites identified near Heathcote (Gibbens 2000), namely species in the genera such as Nasutitermes and Amitermes (Termitidae), are likely to have non‐commercial ecological impacts only. Their diets comprise of weathered or decaying wood in stumps or soil, plant detritus and grasses (Watson & Gay 1991). Ecological functions of termites include nutrient cycling and providing a food source for other invertebrate predators and decomposers at the forest floor. Colonies are very long‐lived and trees are often eaten out internally from the base to the branches (Elliott et al. 1998), but trees are rarely killed as a result of termite attack. Termites also have a

30 Box‐Ironbark Silviculture Reference Manual role in the formation of hollows in older trees that may provide nesting sites for native mammals and birds (CFL 1989). Some wasp and ant species (described in section 2.2.3) damage eucalypt seeds, but Iridomyrmex (purpureus group) (meat ants) and Notoncus enormis have no effect on seed supply. The former group functions as scavengers, capable of stripping small dead animals down to their skeletons (Naumann 1991). (Some other invertebrates are covered in more detail in section 2.2.3). 2.1.3 Geology, soils and nutrition Box‐Ironbark vegetation is very closely associated with Silurian and Ordovician sedimentary formations (mainly mudstones and shales) on the inland slopes, as well as Quaternary alluvial terraces above the present flood plains (ECC 1997). Harder strata, mainly of metamorphic rocks, occur as isolated rocky hills, contrasting with the widespread undulating landscape. Granitic intrusions through the ancient sediments result in higher boulder‐strewn hills, such as at Kooyoora State Park (VNPA 2002). There is a range of soil types in the Box‐Ironbark forests, with the main ones described below (after Gibbons & Rowan in ECC 1997‐ pp.39‐41). The majority are generally shallow and derived from clay‐rich sediments which are low in nutrients (VNPA 2002). Bleached duplex soils These soils have dark, greyish‐brown, hard‐setting loam topsoil, with a conspicuously bleached A‐2 horizon, usually containing ironstone gravel. The B horizon is greyish‐ yellow, brown or red dispersible clay. When dry, the A‐2 is cemented and nearly impenetrable to plant roots. This type is common on the low hills and slopes. E. leucoxylon and E. microcarpa are common on these soils, although E. microcarpa is often found in pure stands on wetter soils. Red duplex soils These have hard‐setting, brown, loamy topsoils with a paler A‐2 layer overlying reddish‐ brown, blocky‐structured, sodic B horizon. These soils are acidic, with low cation exchange capacity and low nitrogen and phosphorous levels. Such soils originally carried extensive areas of grassy woodlands with E. albens and E. microcarpa, with some E. tricarpa. Shallow soils These soil types are found mainly on dry ridges, where depth to bedrock is less than 60 cm. Their profile is mostly stony and gravelly, although on granitic parent material it

Box‐Ironbark Silviculture Reference Manual 31 is sandy. These sites commonly support E. polyanthemos, E. goniocalyx and E. macrorhyncha. Poor loams and earths These types of soils include gravelly duplex soils with ironstone or silica hardpans, which occur on remnants of Tertiary laterite or sands on mid‐slopes, such as in the Campaspe River catchment. They have low available water storage and very low nutrient levels. They often carry E. tricarpa or E. sideroxylon forests. 2.1.4 Hydrology The Box‐Ironbark forests include parts of the catchments of the Wimmera, Avoca, Loddon, Campaspe, Goulburn, Broken and Ovens Rivers, all of which are north‐flowing tributaries of the Murray River. The direct relevance of river water resources to Box‐ Ironbark vegetation is limited, but these forests occur in important recharge areas for groundwater systems, and thus play a role in reducing dryland salinity downslope (Muir et al. 1995). In most of the areas, ground water tables have risen since European settlement. The main cause has been increased recharge through irrigation or the clearing of native vegetation. In particular, the clearing of Box‐Ironbark vegetation has turned many hills and slopes into major recharge sites (ECC 1997). 2.2 Ecosystem dynamics 2.2.1 Fire ‐ its role and influence Like most other forest types in Australia, the Box‐Ironbark forests have evolved with fire as a feature of the ecosystem. Even before the arrival of the Aborigines (over 40,000 years ago) lightning would have started bushfires that burned until rainfall extinguished them or they ran out of fuel in recently burnt areas. Aborigines clearly used fire in a loosely managed way to flush out animals and create areas with fresh grass (Hateley 2010), and this would have killed some trees and promoted seedling and coppice regrowth. However, at least since around 1900, fire has played a relatively minor role in shaping the natural environment in the Box‐Ironbark region (ECC 1997). This is because bushfires are typically much less extensive, less intense and possibly less frequent than fires in adjoining major regions such as the mallee and the mixed species forests in south west Victoria (ECC 1997, Bennett et al. 2012, Tolsma et al. 2010). Reasons for this include lower biomass, especially of the litter and shrub layers, and better road access thus expediting fire‐fighting operations. The largest bushfire in Box‐Ironbark country in

32 Box‐Ironbark Silviculture Reference Manual recent years was the 1985 Avoca/Maryborough fire, which covered 50,800 ha, including 17,600 ha of Crown land (mostly forest). Prescribed (or fuel reduction) burning (FRB) in these forests has become more common in recent years. For example, approximately 11,000 ha of forest managed by DEPI and Parks Victoria were planned for FRB in 2013/14. Occasionally, such burns are not so well controlled, leading to extensive scorch and sometimes the killing of trees (Forest Solutions 2013), with the thinner‐ barked E. leucoxylon more susceptible to damage than the other common eucalypt species (Figure 14). Such fire damage, apart from mortality, will reduce both tree growth (due to loss of leaves) and the quality of the timber, sometimes necessitating salvage harvesting. However, all eucalypt species in the region have the ability to recover from fire damage by means of epicormic Figure 14. E. leucoxylon trees fire shoots from the trunk and the basal lignotuber. In damaged during a fuel reduction harvested areas, the practice is to not schedule burn east of Bendigo during the burns until (coppice) regrowth is at least eight burning season 2013/14. These trees metres tall in order to minimise the risk of were recovering with epicormic growth during March 2014. damage (Fagg & Bates 2009). Various reports (e.g. Dexter 1960, ECC 1997 and DSE 2008) have pointed out the negative impact that frequent fuel reduction burning has on surface organic layers in the Box‐Ironbark forest areas ‐ such as impoverishing soils that are often skeletal and already nutritionally low due to past mining, grazing and earlier fires. In summary, regular, extensive planned burning will result in some soil degradation and damage to eucalypt trees, especially where fire intensity is excessive. 2.2.2 Storms Box‐Ironbark forests (like other forests) are occasionally severely damaged by tornadoes or high winds. Early records indicate that forests in the Box‐Ironbark region suffered significant wind damage, either through breakage or uprooting of trees. Localities mentioned by Hateley (2010, pp. 148‐161) include: near Heathcote (1836), St Arnaud (1875), and near Maryborough, Majorca and Castlemaine (1897).

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Some storms in recent years have resulted in wind‐throw of trees in parts of the forests. Where these trees contain saleable timber, they are salvaged before they rot away. If the tornado is fierce enough to uproot trees, the resultant mineral earth seedbed might result in some seedling establishment if a seed source is available. Winds that (only) twist off tops of trees and limbs will inflict severe structural damage, but the trees will recover by means of epicormic shoots. 2.2.3 Organisms that may reduce tree growth Fungi Cinnamon Fungus (Phytophthora cinnamomi) Cinnamon Fungus is an introduced water mould (Weste 1974) rather than a fungus, although it is still referred to as one. It destroys the fine and main roots of many tree and shrub species, both native and exotic. The plant’s ability to take up water and nutrients is lost as the root system dies, and early symptoms of infection may be similar to drought stress. If the attack becomes more severe, leaf fall, death of branches and death of the tree can result. Early indications of disease presence are often shown in the understorey, where plants of the families Proteaceae, Dilleniaceae and Epacridaceae and the genus Xanthorrhoea are especially susceptible, although there is variation in the susceptibility within genera within families. The fungus is soil‐borne and its ‘swimming’ spores (zoospores) are carried through the soil by the movement of water. As infected plants die, the pathogen produces ‘non‐swimming’ chlamydospores that survive in the soil through harsh conditions and can germinate and attack host roots when more favourable conditions return (Marks & Smith 1991). Introduction to non‐ infected areas occurs when soil adheres to vehicles or boots, or where gravel carrying these spores is used for road construction. Many factors, including species susceptibility, stand density, site characteristics such as topography and soil types, climate and fire history influence the development of the disease. In terms of ecosystem dynamics, there is a difference in tolerance to the disease between the two major eucalypt sub‐genera, Symphyomyrtus and Monocalyptus. The gums, ironbarks and box type eucalypts (all in Symphyomyrtus) are far more tolerant or resistant to P. cinnamomi (Marks et al. 1973, Marks & Smith 1991). In recent years, the understorey (mainly Xanthorrhoea australis) of small areas of Box‐ Ironbark forest south of Rushworth has been found to be damaged by P. cinnamomi. (D. Smith, DEPI, pers. comm.). There are also some dead and dying E. tricarpa in the same areas, probably caused by prolonged soil drought rather than P. cinnamomi.

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Control of the spread of P. cinnamomi in public land in Victoria is now being managed under a strategy, including measures to minimise spread of infected soil and gravel (DSE 2008), and new standard operating procedures and guidelines are being developed to deal with the threat (D. Smith, DEPI, pers. comm.). Appendix A contains draft prescriptions for minimising the spread of P. cinnamomi in Box‐Ironbark areas where timber harvesting is planned. Honey Fungus (Armillaria luteobubalina) Unlike Cinnamon Fungus, Honey Fungus is a native, rather than an introduced, root rot. It is found in many Victorian forest areas but is most prominent in some mixed species forests south west of Melbourne. It has had its greatest impact in the Mount Cole Forest, where it was first diagnosed in the 1970s (Kile 1981). Its occurrence, appearance and behaviour in Victoria have been well described by Smith and Smith (2003). Honey Fungus is rare in Box‐Ironbark areas, probably due to the relatively dry and warm climate compared with areas such as Mount Cole. Nevertheless, common Box‐Ironbark species such as E. leucoxylon, E. melliodora and E. macrorhyncha have been recorded as hosts of Armillaria luteobubalina (Kile 2000). Other fungi Most Box‐Ironbark eucalypt species are affected to varying extents by fungi that cause decay in tree butts, major roots, upper trunks and branches (Kile & Johnson 2000). Common (native) genera include Hexagonia (White Rot), Phellinus (White Pocket Rot), Inonotus (White Pocket Rot) and Piptoporus (Brown Rot) (Marks et al. 1982, Kile & Johnson 2000). Park et al. (2000) recorded the leaf spot Phaeophleospora epicoccoides as one of the most common and widespread leaf diseases of eucalypts, including E. sideroxylon, and ‘ring infection’ (Phaeothyriolum microthyrioides) has been identified on E. polyanthemos amongst other eucalypts. The leaf fungus Mycosphaerella spp. may cause leaf blotches, spots and defoliation of many eucalypt species. In general, however, the Box‐Ironbark eucalypts are not seriously damaged by such native fungi. Invertebrate species Mottled Cup Moth (Doratifera vulnerans) The Mottled Cup Moth is a native lepidopteran species, the larvae of which are capable of causing significant defoliation to large tracts of native forest, albeit on an infrequent basis. Reports indicate that Doratifera spp. have caused significant defoliation of various eucalypt species in the Castlemaine‐ Fryerstown area in the years 2011‐2014. Severe Mottled Cup Moth attack often occurs in combination with the Gumleaf Skeletoniser (see below). Little is known of the underlying causes of sudden build‐ups in

Box‐Ironbark Silviculture Reference Manual 35 populations leading to defoliations. These could include suitable climatic conditions, host plant availability, lower levels of control organisms such as disease, and predatory flies, wasps and bugs (Elliott et al. 1998). Gumleaf Skeletoniser (Uraba lugens) The Gumleaf Skeletoniser is a common native insect which is widespread in Victoria. Outbreaks of defoliation of E. tricarpa, E. microcarpa and E. leucoxylon in the Maryborough, Dunolly and Bendigo areas in 2013/14 were largely caused by its larvae. In the previous two years, defoliation was observed in the Dunolly, Bealiba, Tarnagulla and Kingower areas (P. Bates, DEPI, pers. comm.). Fortunately, the impact of this native insect is usually short‐lived, with most trees recovering via epicormic shoots within 9‐12 months. Apart from the significant aesthetic impact, temporary loss of timber volume growth, buds and flowers are the main effects. The main outbreak of Gumleaf Skeletoniser in 2005 in East Gippsland appeared to be linked to below average rainfalls in the previous three years (Collett & Fagg 2010), although above average rainfall was correlated with the recent outbreaks in the Bendigo region (P. Bates, DEPI, pers. comm.). Psyllids Psyllids are a diverse and widespread group of tiny native insects of the sub‐order Homoptera, which feed by sucking sap from leaves and young shoots. Most species build lerps, which are protective coverings for the soft‐bodied nymphs, and are made from excreta rich in carbohydrates (Elliott et al. 1998). The lerps of different psyllid species have distinctive shapes and sizes. Glycaspis is a genus with many species, often found on eucalypt leaves, and attended by ants and birds seeking honeydew secretions. From time to time there are localised outbreaks of native psyllid insects which temporarily disfigure and damage eucalypt foliage in Box‐Ironbark forests. Although in recent years, psyllids have not been observed to be in such density as to affect tree health. Following such outbreaks, the populations usually crash within three years, triggered by a major decline in the quantity of foliage suitable for feeding and oviposition. Native birds, other insects (including tiny wasps), spiders and certain fungi exert natural biological control (Loyn et al. 1983). Wasps, ants and termites In dry open‐canopied eucalypt forests with relatively sparse litter cover on soils, such as the Box‐Ironbark type, the potential of trees to regenerate naturally from seeds may be substantially reduced through the activity of tiny wasps of the genus Megastigmus

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(Hymenoptera: Torymidae), whose larvae are capable of destroying viable seeds within closed capsules high up in tree crowns (Pederick 1960, Boland & Martensz 1981, Neumann & Collett 1998). In coastal forests of New South Wales, Drake (1974) observed Megastigmus attack in capsules of ironbark species such as Eucalyptus crebra (Narrow‐leaved Ironbark) and E. drepanophylla (Grey Ironbark). Significant seed losses can also occur at the forest floor from seed‐harvesting ants such as Rhytidoponera spp. (metallica group) (Green‐head Ants) and Pheidole spp (Seed‐ harvesting Ants) observed near Heathcote (Dexter 1960, Gibbens 2000, Slijkerman 2007). However, only a few species are actually capable of either degrading or destroying large amounts of heartwood within stems and large branches of living or dead trees. Most susceptible are fire‐scarred older trees affected by fungal decay (Perry et al. 1985). Examples of economically important termites are species of the widely distributed genus Coptotermes (Rhinotermitidae) (CFL 1989). Vertebrate species Animals which eat young eucalypt growth include the native Swamp Wallaby (Wallabia bicolor) and the introduced European Rabbit (Oryctolagus cuniculus). Further details relating to browsing animals are found in section 3.3.6. Damage to seedlings and saplings in Box‐Ironbark forests caused by these species is usually localised and spasmodic, but where it is serious, it may necessitate the implementation of control works such as repellents, fencing or tree guards (see Poynter & Fagg 2005 for more detail). Plant species Coarse Dodder‐laurel (Cassytha melantha) C. melantha is a native hemi‐parasitic vine which is widespread in lower‐elevation Victorian forests, but which is very common in parts of the Box‐Ironbark area (Figure 15). It has a long, tough, branching stem system fastened by suckers (haustoria) to host plants (Pederick & Zimmer 1961). The leaves are reduced to small scales but the green stems (2‐4 mm diameter) can photosynthesise. The succulent green fruit contains one seed which may remain viable in the litter or soil for at least 10 years. Germination occurs during spring and once the filiform seedling contacts a host plant, such as grass or a small wattle, it coils firmly around it and develops the haustoria, after which the basal section of the stem dies and the plant becomes independent of the soil. Unattached seedlings die in the following summer (Pederick & Zimmer 1961).

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Figure 15. (a) Paul Bates (DEPI) beside a planted E. microcarpa (Grey Box) infested with Dodder‐laurel near Bendigo. (b) Advanced regrowth of E. tricarpa, killed by Dodder‐laurel, now also dead. The vine spreads from host to host, but generally is most vigorous on eucalypt coppice regrowth which it may often kill by its parasitic smothering. If the host dies or is killed, the C. melantha will also die (Figure 15). It will climb into the crowns to heights of over 8 m and it can also spread many metres along the ground from an existing infestation (Pederick & Zimmer 1961), which decreases the chance of eucalypt seedling establishment. Most eucalypt species in the Box‐Ironbark areas are susceptible, but the main ‘damage’ is most obvious on E. tricarpa and E. microcarpa. Common, non‐eucalypt hosts include Acacia acinacea (Gold‐dust Wattle), Pultenaea largiflorens (Twiggy Bush‐pea), Cassinia arcuata (Drooping Cassinia), and Bursaria spinosa (Sweet Bursaria) (Pederick & Zimmer 1961). The limiting factor, as to whether a young eucalypt can be successfully attacked, appears to be the height of the lowest foliage or the bark thickness. It cannot attach to the thicker bark which occurs on box and ironbark eucalypts once they reach 8‐10 cm DBHOB, so as a tree grows, the vine moves up the tree to where the thinner bark is.

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It is thought that the incidence of C. melantha increases with periodic timber harvesting, which usually results in the rejuvenation of ground flora and coppice that act as ‘stepping stones’ for the vine to clumps of coppice that are easy and ‘juicy’ targets (Gill 1936). Wallabies, rabbits and birds can ingest the seed and spread it to uninfested areas, although the normal means of spread is vegetative. For control of C. melantha, Pederick and Zimmer (1961) investigated slashing and heaping, burning, and chemical spraying, all of which were not effective, but intensive grazing by sheep was temporarily successful. In the mid‐1980s, a large field trial was established in the Wellsford State Forest where there was major infestation. All box and ironbark trees (together with any attached vines) were felled, the area was burnt and treatments were applied two years later. After four years, the most effective treatment was thinning and pruning of the coppice stems together with spraying glyphosate in a 2 m radius circle around each coppice clump. The spraying killed understorey plants that could act as a ‘ladder’ to assist spread of dodder to the eucalypts, but the intensive felling and burning were deemed to not be necessary for dodder control (Fagg & Squire, DCNR, unpublished).

Mistletoe (Amyema spp.) The Box‐Ironbark forests appear to be particularly affected by infestations of the semi‐ parasitic native Amyema pendula (Drooping Mistletoe) and A. miquelii (Box Mistletoe) (Kellas 1991, Fagg 1997). In 1996 in Sandon State Forest, 80‐90% of the E. tricarpa, E. leucoxylon and E. melliodora trees supported mistletoe plants (Hateley quoted in Fagg 1997). Other common Box‐Ironbark eucalypts, such as E. sideroxylon, E. microcarpa and E. polyanthemos are often infested with the above mistletoe species (Reid & Yan 2000), with the frequency higher where the forest abuts farmland. Mistletoe flowers and foliage are important as a food source for some native fauna (see section 2.1.2). The Mistletoebird is able to partly digest the mistletoe fruits and excrete viable seed directly onto the tree branch. The seed germinates and a wedge of haustorial tissue penetrates the bark by a combination of mechanical pressure and enzymic digestion (Reid & Yan 2000). Branch diameter and bark thickness determine establishment success for most mistletoe species. In a study of heavily infested E. melliodora, the majority of host branches were less than 30 mm in diameter (Reid & Yan 2000). Where dense (>5 clumps per tree), mistletoe has a negative effect on the health of most host eucalypts, which can result in reduced growth, dieback and sometimes death (Reid & Yan 2000). Control of mistletoe in native forest is difficult and can only be recommended in very limited situations. Fagg (1997) lists three possible methods:

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1. Physical removal by pruning off limbs 2. Removing the whole tree, in the course of thinning for firewood or posts 3. Herbicide application ‐ by injection into the host tree (Minko & Fagg 1989) or direct spraying.

Other plant species Two exotic plant species of some concern which occur in places within the Box‐Ironbark forests are the European Blackberry (Rubus fruticosus spp.) and Gorse (Ulex europaeus). These woody, prickly weeds tend to invade disturbed areas. Herbicides are often used to limit their spread, as biological control by the Rust Fungus Phragmidium violaceum (for Blackberry) currently only has a limited impact (Adair & Bruzzese 2006). Other fungi with potential for biological control are being investigated. Other locally invasive, environmental weed species, recorded by Muir et al (1995) included Acacia baileyana (Cootamundra Wattle), Genista linifolia (Flax‐leaf Broom), Chrysanthemoides monilifera (Boneseed) and Myrsiphyllum asparagoides (Bridal Creeper).

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3. Silvical features of Box‐Ironbark eucalypts 3.1 Sources of regeneration In most eucalypt forest types, seedlings, lignotuberous seedlings (Figure 16) and coppice (in that order) are the main sources of regeneration. In the Box‐Ironbark forests, however, coppice is the most common source of regeneration following harvesting, but some seedling regeneration from seed is required for long‐term sustainability (Kellas 1991). All sources of regeneration are counted in stocking surveys, provided they meet the acceptability criteria (Bassett et al. 2014a)10. 3.1.1 Seedlings Seedlings are plants that have grown directly from seed. They may naturally occur after a bushfire or other disturbance following the fall of seed from standing trees. Collected seed may be spread artificially to produce seedling regeneration after timber harvesting, or it may be used in a nursery to raise seedlings for later planting out. Seedlings of all Box‐Ironbark species produce lignotubers early in their life (see section 3.1.2). In the Box‐Ironbark Timber Assessment Survey (NRE 1998), 25% of the established trees were estimated to be of seedling origin and 75% to be of coppice origin. However, this varied widely across the study area and determination of the origin of advanced trees is difficult. Edgar (1960) noted that a flush of E. sideroxylon seedlings occurred around 1890 in the Chiltern forest. Natural seedling establishment is problematic in E. tricarpa, being limited by low seed and infrequent seed fall, loss of seed locked in fallen capsules (Dexter 1960), severe overwood competition (Kellas et al. 1982, Bassett & White 2001), often unreceptive seedbeds and a low frequency of bushfires. Achieving regeneration after deliberate sowing has also historically been difficult (Forest Solutions 2013, Orscheg 2011). Root:shoot ratios of seedlings Zimmer and Grose (1958) grew several species of eucalypt from the Box‐Ironbark type in seed boxes (with grey, peaty sand) and measured root:shoot ratios based on both relative lengths and oven‐dry weight. The ratios (summarised in Table 6) show that roots for the four Box‐Ironbark species in terms of length are many times (6‐8) longer than the shoot, yet in terms of weight, are only approximately 0.6 times that of the shoot, with the exception of E. microcarpa.

10 Native Forest Silviculture Guideline No. 10 Stocking Surveys (Dignan & Fagg 1997) has been revised and updated in a second edition (Bassett et al. 2014a).

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Table 6. Mean root:shoot ratios for selected eucalypt species (from Zimmer & Grose 1958)

Mean root:shoot ratio Length Oven‐dry Oven‐dry Species Locality (14 weeks) weight weight (18 weeks) (10 weeks) E. microcarpa Heathcote 6.9 1.04 E. leucoxylon St Arnaud 6.6 0.57 E. polyanthemos Daylesford 7.4 0.56 E. tricarpa Dunolly 8.1 0.57 St Arnaud 0.66 Heathcote 0.65 Chiltern (sideroxylon) 0.66 Heyfield 0.45 Airey’s Inlet 0.47 E. obliqua Daylesford 3.3 0.35 E. sieberi Neerim 2.7 0.39

It was observed that, for all four species the typical root system (after 10 weeks) was a single tap root, 10‐12 cm long with very few short laterals. This was in contrast to eucalypts from normally damper environments, such as E. sieberi and E. obliqua (Messmate Stringybark) which had fibrous and more branched root systems. The study showed that eucalypts typical of low rainfall areas, in contrast to those of moister zones, develop long tap‐roots with weak laterals and small shoot systems in the early seedling stages. In Box‐Ironbark field situations, however, seedling root systems would struggle to penetrate the normally dry, hard clay‐rich soils. Figure 16. An excavated E. tricarpa Shoot growth would be correspondingly less, and seedling showing a single, long tap‐ young small seedlings would be vulnerable to root with lignotuber. This seedling desiccation, insect attack, and browsing for regenerated after the 1985 longer. Therefore it can be concluded that a Maryborough bushfire and was friable seedbed of some depth (at least 15‐20 cm) excavated in 1992. (The 50c coin is is important for successful eucalypt seedling included to give a sense of scale). establishment in most Box‐Ironbark areas.

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3.1.2 Lignotuberous seedlings These are eucalypt seedlings that become established under a forest canopy and have lignotubers (Figure 16) older than the shoots they support (see Glossary for ‘lignotuber’). That is, the original shoot has died back due to competition or browsing, and the dormant buds in the lignotuber have responded with new shoots. The density of lignotuberous seedlings in an area depends on the ability of seed to germinate and become established under a canopy, and this varies considerably between species. Such seedlings are shade‐tolerant and can sit ‘dormant’ under a canopy for years then ‘take off’ (Florence 1996), although one author (Fagg) has observed extreme competition eventually killing suppressed lignotuberous seedlings. 3.1.3 Coppice Coppice is a stem (or often several stems) arising from previously dormant buds in recently cut stumps, and can develop mature, stable stems (Figure 17). In Box‐Ironbark forests, regeneration by coppice is heavily depended on after timber harvesting. All Box‐Ironbark eucalypt species have the potential to coppice from healthy cut stumps, but evidence provided by local DEPI staff suggests that, on average, approximately 90% of stumps successfully coppice, leaving a small shortfall.

Figure 17. (a) Mature E. microcarpa (Grey Box) stems originating as coppice from what is now an old and rotting cut stump, and (b) young E. tricarpa (Red Ironbark) coppice establishing.

In dry years, however, 50% of fresh stumps may not coppice or will die within three years (Fagg & Bates 2009). There will therefore be a gradual reduction in stocking (stems/ha) over time, with gaps in the forest becoming larger unless some seedlings

Box‐Ironbark Silviculture Reference Manual 43 become established. This is a long‐term issue (Ferguson 1934) that should be addressed by establishing more seedlings, to arrest gradual forest decline (Forest Solutions 2013).

3.2 Seed production 3.2.1 Flowering and seed development Flowering studies Knowledge of flowering behaviour in Box‐Ironbark forests is important to apiarists for honey production (Goodman 1973) and to foresters for understanding seed development during timber production (Bassett 2014)11. Flowers also form an important food resource (nectar and pollen) for insects and fauna (see sections 2.1.1 and 2.1.2), which in turn provide a source of pollination. It is therefore helpful to consider these forest uses collectively and not in isolation, given they all depend on the flowering stage. The Box‐Ironbark eucalypts possess a breeding biology that is considered typical of the genus Eucalyptus for south‐eastern Australia (Florence 1996), and follow four general stages of development which are detailed in NFSG No. 1 (Bassett 2014). They are summarised as: (1) Inflorescence stage (2) Umbellate bud stage (3) Flowering stage, including pollination and fertilisation (4) Seed development stage, including seed maturation and dissemination from capsules. The need to investigate eucalypt flowering and seed development in Box‐Ironbark forests has long been recognised (e.g. Dexter 1960), but most ecological/silvicultural studies of flowering and seed development have focused on other more commercial forest types and species. The Victorian Government’s Silvicultural Reference Manuals Nos 1‐3 provide a good overview of these studies (Flint & Fagg 2007, Sebire & Fagg 2009, Murphy et al. 2013). Table 7 provides a summary of flowering and seed development studies undertaken for some Victorian Box‐Ironbark eucalypt species. Although most of these studies have focused almost exclusively on the flowering stage for non‐silvicultural purposes, the outcomes are valuable to all the forest uses and processes mentioned above.

11 Native Forest Silviculture Guideline No. 1 Seed Crop Monitoring and Assessment (Wallace 1993) has been revised and updated in a second edition (Bassett 2014).

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Table 7. Summary of flowering studies undertaken on Box‐Ironbark Eucalyptus species

Reference Main Main reason Location* Description of study eucalypt for study species Dexter (1960) tricarpa Seed Rushworth Investigated the problem of production achieving seedling regeneration for forest in E. tricarpa, including a regeneration flowering and seedfall study over a single season. Porter (1978) tricarpa Honey Bendigo Based on apiarist observations production over 22 years and throughout 19 forest sites. Flowering described annually by intensity. Moncur & Boland melliodora Flowering Australian Intensive description of floral (1982) biology Capital stages based on only seven Territory adjacent trees. Keatley (1999) PhD tricarpa Flowering Maryborough PhD based on the long‐term and various leucoxylon phenology records collected by the Forests published articles microcarpa Commission (1940‐1970), which were compared with a up to 2013, often polyanthemos alongside Hudson more detailed 3‐year flowering melliodora and others (see study (1996‐1998). Focused on Manual reference temporal and spatial flowering list). patterns within and between species. Later focused on climate, both as an influence on flowering and flowering as an indicator of climate change. Keatley & Murray tricarpa Seed East Floral component trapping at (2010) production Gippsland two sites over four years to for forest develop a budget of capsule regeneration set. Seedfall also monitored. Wilson (2002) PhD tricarpa Flowering Rushworth Studies included floral Wilson & Bennett leucoxylon ecology morphology, timing of (1999) microcarpa flowering, the frequency, duration and intensity of polyanthemos flowering, synchrony between melliodora trees and the influence of tree macrorhyncha size. Measurements based on camaldulensis periodic crown cover by flowers. Also soil moisture influence on flowering. Mac Nally et al. tricarpa Bird Numerous Flowering measured as food (2009) and various populations sites, north resource for birds. Non‐ other publications, central operculum study, observing including A. Victoria scored flowering intensity Bennett data. along transects. *All studies were in Victoria except that of Moncur & Boland (1989)

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The most significant flowering studies for Box‐Ironbark eucalypts are the PhD theses of Keatley (1999) and Wilson (2002). Keatley’s thesis is particularly important given the component based on the long‐term flowering observations of Mr. William Sheen who was a forest overseer employed by the Forests Commission Victoria (FCV) with charge over Havelock Forest Block, Majorca and parts of Craigie Forest Block ‐ all in the Bendigo Forest District. Sheen kept diary records between 1940 and 1970 which were used as a basis for completing the FCV budding and flower reports (‘Forms 336 and 336A’), giving 30 years of observational data. Other forest types were monitored using these reports, however, the rare Box‐Ironbark ‘Sheen data set’ is highly valuable given it is continuous and was compiled by a single observer. This data set has enabled Keatley to verify the validity of her shorter‐term, more recent measurements against long‐term flowering observations.

Budding The following characteristics relate to E. tricarpa. (They could also apply to the closely‐ related E. sideroxylon, but this is uncertain.) Dexter (1960) makes specific reference to inflorescence buds being ‘basitonic’, that is, they are formed within axils of the first‐ formed leaves of the annual shoot which subtend them. Carr and Carr (1968) found that the umbellate buds are enclosed by two elongated bracts typical of the large floral morphology of this species. In East Gippsland, Keatley and Murray (2010) recorded the first aborted umbellate buds in November or December, indicating bract shed occurred about then. A study in western Victoria (Keatley 1999) concurs with these observations; umbel buds first appeared from inflorescence buds in December and finished with the commencement of the flowering period at least 11 months later in October/November. E. tricarpa produces three buds per umbel, while E. sideroxylon produces up to seven (Bramwells & Whiffan 1984), a major feature separating the two species. E. tricarpa can carry umbellate buds in all months of the year. This usually indicates multiple bud crops are developing (consecutive years). During Keatley’s long‐term study (1940‐1970), budding success12 was higher than flowering success, indicating complete loss of buds in some years. In the East Gippsland study, losses recorded over three years (1994‐1996) accounted for 59‐92% of the umbellate bud crop (Keatley & Murray 2010). Such high losses of umbellate buds in dry forest eucalypts have been recorded elsewhere (see Bassett 2014, Keatley & Murray 2010, Bassett 2002) and are caused by competition for resources and insect damage. The larger proportional losses are usually associated with

12 Budding success is the proportion of years when umbellate buds where noted to be present in the long‐term study undertaken by Keatley (1999), and is irrespective of bud density.

46 Box‐Ironbark Silviculture Reference Manual smaller bud crops. Extended flowering does not occur in E. tricarpa, indicating that no buds are carried over inter‐season (Hudson & Keatley 2013). Porter (1978) indicates that bud development (continuity through to flowering) is assisted by suitable temperatures for growth (threshold is >16‐17 oC) and rainfall (>45 mm/month) over the summer months. As a central Victorian example, Bendigo’s long term average summer rainfall is about 38 mm/month, with extreme evaporation possible (average 156 mm/month), indicating that rainfall in some summers is inadequate to support good bud development. Keatley and Hudson (2012) examined the relationship between budding and flowering cycles of four eucalypt species, E. leucoxylon, E microcarpa, E. polyanthemos and E. tricarpa. E microcarpa was the only species which did not carry buds in all months, indicating a distinctive and identifiable budding period. In contrast, E. leucoxylon carries umbellate buds in all months of the year, indicating multiple bud crops are developing or buds have been carried over to flower alongside next season flowers, a mechanism possible in this species (Hudson & Keatley 2013). Over the 30‐year study in Havelock Block (Keatley 1999), the bud stage generally commenced in January and finished in December of the same year with the start of flowering. Budding success12 is very consistent between years. For example, in the Havelock study, umbellate buds were present in all of the 23 years monitored. It is concluded that E. leucoxylon will also lose a lower proportion of umbellate buds than E. tricarpa, leading to a higher flowering success (Keatley 1999, Keatley & Hudson 2007). The E. tricarpa and E polyanthemos budding period is similarly less defined, but to a smaller degree. The success of buds developing into flowers was strongly correlated for E. leucoxylon and less so for E. polyanthemos, the species within which bud‐crop loss occurred more readily, indicating most strongly that the presence of buds in that species does not guarantee a flowering event. For E. melliodora, Moncur and Boland (1982) noted that bracteate inflorescence buds first appeared in early February to mid‐March in the axils of new leaves on terminal shoots, although it should be noted that their study lasted only for one season. The two bracts split and shed by early April, revealing the enclosed umbellate buds. E. melliodora therefore has a very short inflorescence period, and given flowering does not occur until spring, the umbellate buds are exposed to losses caused by environmental factors for longer prior to flowering. E. globoidea (White Stringybark) behaves similarly, leading to large proportional losses of exposed umbellate buds (Bassett 2002). In E. melliodora, umbellate buds continued to increase in size until June, at which time they were then near maximum size. In the ACT population, buds

Box‐Ironbark Silviculture Reference Manual 47 remained for a further five months, after which time flowering began in late November (Moncur & Boland 1982). The ACT E. melliodora results for the timing of events may be misleading for Victoria, as Keatley found E. melliodora to be the most spatially heterogeneous species for flowering behaviour, seemingly with few predictable patterns between different sites, referring to this species as being generally ‘discordant’. The flowering process Flowering begins with the separation and falling away of an ‘operculum’ cap from the top of an umbellate bud, to allow the enfolded anthers to open. Anthers carry pollen and the floral tube (stigma) secretes nectar to attract nectarivores, enabling cross‐ pollination for fertilisation. E. tricarpa and E. leucoxylon have two fused opercula, so they shed as a single unit, revealing a range of either red, pink or white flowers (Brooker & Slee 1996, Figure 18). This characteristic has enabled quantitative measurement of operculum fall from E. tricarpa over time (Keatley & Murray 2010). (Refer to NFSG No. 1 for a more detailed description of the flowering process for Eucalyptus generally).

Figure 18. (a) Flowers of E. leucoxylon (Yellow Gum) and (b) E. tricarpa (Red Ironbark). An operculum can be seen separating from the floral tube in Figure (a). E. tricarpa flowers also occur in lighter shades of red (pinks) or cream.

In E. tricarpa, there is an inner and outer ring of stamens, with the outer stamens supported by a staminophore which eventually abscises and falls away after flowering is finished (50 days). In the majority of flowers, only the outer stamens totally abscise, often leaving an inner ring of collapsed stamens covering the hypanthium (Figure 19). This characteristic of retaining inner stamens is particular to E. tricarpa only and has significant silvical implications in relation to later seed shed (see section 3.2.3).

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Figure 19. (a) The inner staminal ring can be seen still attached to an immature E. tricarpa capsule following flowering and capsule swelling, leading to a blocked hypanthium (b) at capsule maturity. Webbing can be seen behind the retained staminophore, also blocking free seed dispersal.

Timing of flowering Because eucalypts can be so diverse in Box‐Ironbark forests, the most important aspect of flowering behaviour is ‘time of flowering’, the details of which define the individual flowering signature of each eucalypt species as follows: 1. Start and finish time (temporal): the months when flowering starts and finishes. This defines ‘flowering period’ for the season from which a monthly flowering probability can be calculated (as per Keatley 1999). There are normally expected times, creating a ‘signature’ for each species. Deviation from expected has potential management implications, such as seed maturity in silviculture and hive management in honey production. 2. Peak time (temporal): the time when flowering is most intense within the flowering period (defined by peak operculum fall, or proportion of canopy in flower). For example, peak time allows annual flowering intensity to be monitored and seed availability predicted (Bassett 2014), and informs the critical time by which honey bee hives must be in place (Goodman 1973). 3. Synchrony of flowering ‘within’ a forest stand (temporal and spatial): includes synchrony of peak flowering between neighbouring individual trees of the same species, and between different species in the same stand. Synchrony within species indicates the level of out‐cross pollination that can be

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expected. Out‐crossing (pollination between flowers of different trees) is important to maximise reproductive success. Synchrony between cohabiting species in a stand informs inter‐species pollination dynamics, including pollinator selection and the likelihood of hybridisation (Keatley et al. 2004, Wilson 2002). 4. Synchrony of flowering ‘between’ forest‐stands (spatial and temporal): shows how concordant (uniform) a species flowering is within the landscape, that is whether a species occupies the same temporal niche across different, separate stands (Keatley & Hudson 2007). This in turn helps to define the factors which may influence flowering (e.g. genetic, climatic, and/or other environmental aspects). 5. Reliability of flowering (temporal): indices for annual success13 of flowering by species have been developed from the long‐term Havelock data. These can indicate an average success rate (expressed as proportion of years within which flowering has occurred), or average time to next year of annual flowering failure (Keatley & Hudson 2007). This is a useful planning tool for such practical outcomes as managing adequate levels of seed in storage, and indicating likely frequency of honey‐producing months and/or years. When considered for a single species, these details confirm the ‘species signature’, and comparison between species enables a complete picture for the flowering pattern within a Box‐Ironbark forest. Note that not all details are known for every species. Table 8 summarises time of flowering for the common Box‐Ironbark eucalypt species. Appendix B reproduces the detailed ‘Indices of Flowering Behaviour’, based on Keatley and Hudson (2007) for Rushworth and Havelock. Keatley (1999) found that the average flower‐life for individual flowers is 30 days for E. leucoxylon and 50 days for E. tricarpa, but she calculated an average flower‐life for other eucalypts (including E. melliodora from Moncur & Boland 1982) of 13‐32 days. For E. tricarpa, following operculum fall, stamens are fully flexed on the 11th to 14th day, and can be cream or pink to red in colour (Figure 18). Wilson (2002) noted individual tree flowering times of up to 237 days for E. tricarpa during high intensity flowering in 1998. This helps explain why E. tricarpa flowering is often so protracted within a stand. For example, Keatley and Murray (2010) recorded

13 A successful flowering year is a year when flowering occurs somewhere within a stand. The indices of success developed by Keatley are not linked to flowering intensity. The operational implication being that some nectar or seed could be expected to result from a ‘successful flowering year’.

50 Box‐Ironbark Silviculture Reference Manual periods in excess of 200 days/year in their limited East Gippsland study, and Keatley (1999) reported a range of 156‐189 days/year in western central Victoria for the 1940‐ 1970 period. In contrast, the flowering period for other Box‐Ironbark species and eucalypts in other Victorian forest types, is generally much shorter and more defined (Ashton 1975, Bassett 2002, Murray & Lutze 2004).

Table 8. Average time of flowering characteristics for five Box‐Ironbark eucalypts from Havelock 1940‐1970, and Rushworth 1945‐1970. Based on Keatley (1999) and Keatley & Hudson (2007). Shading is only included to assist reading across the table by species.

Eucalyptus Location Commencement Peak Finishing Duration if C Reliability # species month (C) month month holds true range Havelock Apr Jul Sep 6 months tricarpa 80‐90% Rushworth Jan*/Apr Jun Sep 7 months Havelock May Sep Dec 9½ months leucoxylon 100% Rushworth Jan Jul Dec 7 months Havelock Feb Mar May 4 months microcarpa 80‐85% Rushworth Jan Mar May 4½ months Havelock Nov Dec Mar 5 months melliodora 85‐95% Rushworth Oct Nov‐Dec Dec 3 months Havelock Oct Nov Dec 3½ months polyanthemos 65‐90% Rushworth Jul Sep Dec 4 months *summer flowering form of E. tricarpa was detected near Rushworth (Keatley & Hudson 2007), but not by Wilson (2002). #based on a probability, calculated from long‐term data, that flowering will occur within the stated period

A spatial variation study across Rushworth, Bendigo, Dunolly and St Arnaud districts found the percentage of E. tricarpa trees in flower during the heavy flowering year of 1998 to be 12% in April, 50% in June and 30% in September (Wilson 2002). The general range of April‐September also held for two East Gippsland stands (Keatley & Murray 2010). In his Rushworth study, Dexter (1960) recorded flowering between June and September, with a peak in July. Appendix B concurs with this for two other sites. Parrots, such as the Swift Parrot, which feed in flocks on Box‐Ironbark flowers, may cause a significant proportion of the flower crop to fall during feeding. An important variation to commencement of flowering in E. tricarpa is a January start (Table 8), identifying the summer flowering form that has long been recognised by apiarists (Wykes 1947 quoted in Keatley 1999, Dexter 1960). McDonald (1999) even describes a mid‐range ‘variety’, flowering in autumn between the summer and winter ‘varieties’. Keatley and Hudson (2007) in the Rushworth district between 1945 and 1970 found an equal probability (Pr. = 0.43) of flowering starting in January or April

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(Appendix B). However, no summer flowering was recorded within the Havelock Block. Dexter (1960) and Goodman (1973) confirm the summer flowering form near Rushworth and other sites. An unpublished honours thesis (Gloury 1998) suggested a correlation exists between summer flowering and site quality, whereby summer flowering occurs on the drier, more shallow yet fertile soils, and winter flowering occurs on the moister, protected sites, but these findings have not been verified. Mapping of summer‐flowering E. tricarpa stands has identified significant areas in the Bendigo FMA. This will assist silvicultural planning in State forests where honey and timber production objectives overlap. It is interesting to note, as demonstrated in Appendix B, that the month within which peak flowering intensity occurs is often also the month with the highest probability of finding flowers present. Wilson (2002) found this also, indicating that synchronised flowering occurs on a higher proportion of individual trees during peak flowering. This highlights the value of knowing the time of peak flowering and at what intensity, as this can assist with understanding related forest processes (e.g. fauna movement), seed forecasting and development, and likely timing of the best nectar production for apiarists. E. leucoxylon can be found flowering in any month, indicated by relatively high probabilities in all months (Pr. > 0.30, Appendix B). Winter into early spring is the most probable (Pr. > 0.60), but summer flowering in this species is common (Pr. range 0.30 ‐ 0.70). Even so, commencement is fairly constrained largely to the March to July period, with a winter peak in flowering intensity. For some sites, peak flowering can occur rapidly following commencement, being early in the flowering period. However, for other sites, the peak can be delayed up to September, if flowering commencement is late, with flowering commonly continuing into summer (Wilson 2002, Appendix B). Flowering is therefore more spread over the year than in E. tricarpa, and even if their flowering periods are the same, their peaks may not align. Flowering pattern and synchrony Understanding synchrony of flowering within and between species will help interpret flowering pattern and understand the diversity of biological strategies employed by Box‐Ironbark eucalypts. Keatley et al. (2004) quantified synchrony between four species in various combinations, at the tree‐level. The least synchronous were E. polyanthemos and E. microcarpa, with flowering overlapping in only five of the 30 years studied (Pr. = 0.06). The most synchronous were E. leucoxylon and E. tricarpa, with flowering overlapping in 24 of the 30 years studied (Pr. = 0.62) (Figure 20).

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Figure 20. Average monthly flowering intensity of four Box‐Ironbark species from long‐term data (1940‐1970) collected in the Havelock Forest Block (Keatley et al. 2004). Species are E. leucoxylon (), E. microcarpa (), E. polyanthemos (), and E. tricarpa ().

Keatley (1999) demonstrated that E. tricarpa and E. leucoxylon may display their flowers ‘en‐masse’, a strategy for maximum pollinator attraction. Synchrony within species is important for maximum ‘out‐crossing’ pollination (pollen transfer between neighbouring trees), with a minimum reliance on ‘selfing’ (pollen transfer between flowers of the same tree) which can lead to an ‘inbreeding depression’. Seed resulting from such fertilisation is known to have low germination energy (Pederick 1976, Eldridge et al. 1993). Wilson (2002) found that most individual trees within an E. tricarpa stand flowered for a shorter period than recorded for the entire stand, showing that a proportion of the population is not synchronous. This holds more strongly for E. leucoxylon (Keatley 1999). For E. tricarpa, Wilson (2002) also found a strong correlation between the proportion of trees flowering and flowering seasonal intensity. For example, in her 1998 measurement, about 97% of trees in a stand flowered in this heavy flowering year (c.f. 2% in the 1997 light flowering year). Keatley (1999) found that intense stand flowering occurred for this species every four to nine years during the period 1930‐1970. Peak flowering within synchronous species can be offset between species, either as an early peak within the period, or late peak. Keatley refers to this as ‘skewness’ of peak. Where flowering periods of different species overlap at the site‐level, these offset peaks have implications for insect and bird visitation, encouraging within‐species pollination, maximising seed set and avoiding hybridisation.

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A failure to flower at all occurs every 6‐12 years, depending on site (Keatley & Hudson 2007), so that the years in between complete failure years and heavy flowering years are characterised by sporadic flowering of varying intensity. Although such moderate years have ecological and productive value, these findings highlight the ‘bonus’ nature of heavy flowering seasons in E. tricarpa, including potentially increased honey production for longer, the likelihood of heavy seed crops one to two years later, and the specific value to nectarivores as a massive and attractive food resource. Note that flowering periodicity, synchrony and other strategic flowering aspects may vary between stands in the landscape. However, the work by Keatley, Hudson and Wilson provide a bases for understanding the flowering character of these species, and for comparison with real‐time observations from other sites. 3.2.2 Seed quantities For E. tricarpa in East Gippsland, Keatley and Murray (2010) measured quantities ranging from 115,000 to 234,000 viable seeds (vs) per hectare per year across two sites monitored for four years. Dexter (1960) measured about 75,000 vs/ha in his research during the summer of 1959/60. This rate is 10‐20 times smaller than for most other eucalypt forests, therefore not ideal for natural seedling regeneration following harvesting (i.e. not good for seed tree use and difficult for seed collection). Low seedfall (productivity of seed production) is one important reason for the observed low natural regeneration seedling success. Two main reasons for the low seed production (at least for E. tricarpa14) are:  bud and flower losses can be so high that very few capsules are ultimately produced  of those produced, up to 33% of seed is lost by being locked inside capsules due to retention of the staminal ring. Orscheg et al. (2011) studied, ‘inter alia’, the effect of stand competition on ‘reproductive effort’ (i.e. seed production), on replicates of 10 E. tricarpa trees at three sites of varying coppice stem density. Assuming stem density is a measure of competition, they found no impact of density on seed production factors, such as quantity produced, losses (abortion) of capsules and the resulting seed viability. They concluded that stem density has little influence on seed production in E. tricarpa.

14 Apart from E. tricarpa, we have not discovered any studies of seed quantity undertaken for any other Box‐Ironbark species (see Table 7).

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3.2.3 Seed type and dissemination Grose and Zimmer (1958a) describe the seeds of E. tricarpa, E. leucoxylon, E. melliodora and E. polyanthemos. These eucalypts fall within the subgenus Symphyomyrtus, section Adnataria (Pryor & Johnson 1971), with E. leucoxylon seed in particular being similar to E. tricarpa. Fertile seeds are very different to chaff (unfertilised ovules) and stand out in the seed lot – typical of all Symphyomyrtus species. Fertile seeds are dark brown and often ovate or elliptical, in contrast to the orange‐brown Figure 21. Seed from E. tricarpa capsules chaff which is mostly acicular or ‘awl‐ with needle‐like chaff (light orange) and the shaped’; that is, slender, pointed and larger black viable seeds. needle‐like (Figure 21). There is a narrow flange around the fertile seed, but it is only slightly developed offering little benefit during wind dispersal following dissemination. Capsules mature 16‐22 months after flowering (Dexter 1960) with the entire seed production cycle taking 30‐36 months after bud initiation. Seed is usually freely released after valve opening, which occurs due to internal shrinkage during capsule drying (Cremer 1965). Capsule maturity includes the loss of the staminophore, however, as detailed in 3.2.1, the staminophore with the inner stamens can remain fixed (not shed), blocking free dissemination of seed. Capsules can therefore fall with seed still trapped inside, which represents a loss to eucalypt regeneration (Bassett 2002). Dexter (1960) found staminal retention affected up to one third of all capsules. The cavity behind retained stamens creates a niche for spider species, and these have been observed to become lined with white web material (Harwood et al. 2001, see also Figure 19b). The Ramularia fungus has caused seed damage early in the life of capsules of non‐Victorian ironbark species such as E. crebra (Narrow‐leaved Red Ironbark) and E. melanophloia (Silver‐leaved Ironbark) (Brown 2000). On the basis of these and other eucalypt studies (Drake 1974, Bassett 2002), seed can be locked in falling capsules for other reasons (e.g. insect and fungal damage), and it should be considered that total loss of seed ‘locked’ in E. tricarpa capsules may therefore exceed the possible one third related to staminal retention. Such losses no doubt contribute to the relatively small quantities of seed that fall per hectare in this forest type.

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Seedfall peaks are variable but generally follow that of other eucalypts in south eastern Australia, that is, late summer into autumn. Dexter (1960), and Keatley and Murray (2010) both noted that main seedfall occurred within the period December to March, with Dexter also noting a smaller August peak. In the East Gippsland study (Keatley & Murray 2010), seedfall peaked within the late February to mid‐March period over two years, replicated across two sites. This peak timing suggests that seedling germination is largely intended for autumn – similar to many other low elevation eucalypt species in Victoria. The timing of peak natural seedfall is linked closely with leaf‐fall (Keatley & Murray 2010), indicating that seedfall is principally caused by the senescence and drying of capsule‐bearing branchlets. Like all eucalypts in Victoria, fire will induce a sudden release of seed by the rapid drying of capsules and branchlet death due to radiant heat. Seedling recruitment can therefore occur following bushfire, as occurred after the 1985 Avoca‐Maryborough fire (see section 2.2.1). Using a mean seed weight of 0.75 mg for E. tricarpa (Orscheg 2011) with a terminal velocity of 4 m/second (as per formula of Cremer 1977) and released at a height of 20 m in 10 km/hr wind, the horizontal distance travelled would be 14 m, that is, 0.7 x tree height. In contrast, E. microcarpa, being a much lighter seed, might disseminate to 1.5 x tree height under the same conditions. Evidence from Keatley and Murray (2010) suggests that the fall of capsules from E. tricarpa occurs very shortly after seedfall. Peak capsule‐fall occurred within the same December to March period, indicating that empty capsules are not retained on trees for long. 3.2.4 Seed collection and storage Seed collection of Box‐Ironbark species is relatively minor in Victoria15, mainly because forestry operations have historically not depended on sowing for seedling regeneration. When collected seed is required, maintenance of genetic integrity is important (Wallace 1994). Points to note include: 1. Collect seed from stands that show no evidence of hybridisation 2. Collect seed only from stands of natural origin 3. If possible, use seed collected from the harvested coupe 4. If collected seed is to be used ‘off‐site’, the following criteria should be met if possible:

15 A detailed audit of all seed extraction and storage centres in Victoria (Bassett & Paterson 2011) showed that (for Box‐Ironbark species) there was only 11 kg of E. tricarpa, 86 kg of E. melliodora, 109 kg of E. polyanthemos and 18 kg of E. albens in storage, mainly in Gippsland and NE Victoria. These figure had not significantly changed over many years.

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‐ elevation should be within 350 m above to 150 m below the proposed destination of the seed (usually not an issue in Box‐Ironbark areas) ‐ slope >10o to keep seed from drier and moister aspects separate, and ‐ soil from both sites should be derived from similar parent material.

Seed collection is generally carried out by contract seed‐collectors, either by the collection of capsule material (i.e. capsules attached to twigs) from trees felled for timber, or by tree‐climbing and the selective removal of limbs (no more than 50% of the crown) bearing mature capsule crops (Figure 22). The latter procedure allows flexibility of provenance selection, collection where capsule crops are found to be heaviest, and recovery of up to three times more than in ground collection following harvesting. Capsule material removed from branches is transported in containers to central locations where specialised kilns (operating at 38‐40oC) are used to extract the seed. Seeds of each tree species and provenance are stored as separate lots, which may be later mixed just prior to field regeneration usage, if needed to reflect the original forest species Figure 22. Gary Hendy climbing an E. tricarpa composition. near Talbot during a seed collection operation in 2014. It is ideal to have two to three years of seed requirements in storage at any one time, especially for those species with more variable seed crops such as E. tricarpa and E. leucoxylon. Extracted mature seed should be stored in a cool, dry environment. Refrigeration or the use of air conditioners is not essential for seed lots stored for less than six years, as long as conditions are dry and kept at around 150C (Boland et al 1980). The optimal storage temperature is 4oC, in which seed quality can be maintained in excess of 10 years. Immature seed can only be used within the season of collection as

Box‐Ironbark Silviculture Reference Manual 57 has a reduced field performance, and therefore should not be collected in normal circumstances. All details regarding recommended procedures for seed collection and extraction/storage of seed are given in NFSG 1 (Bassett 2014), NFSG 2 Eucalypt Seed Collection (Wallace 1994), and NFSG 3 Seed Extraction, Cleaning and Storage (Wallace & Fagg 1995). In response to the 2013 review of commercial forestry in western Victoria (Forest Solutions 2013), which identified a need to increase the store of Box‐Ironbark species, DEPI collected 6.6 kg of E. tricarpa seed to undertake sowing trials. It is worth noting that these collections were not considered ‘commercially viable’, that is, not remunerated at a $/kg rate. Instead, seed collectors were paid an hourly rate due to low capsule densities, low overall available quantity, and poor seed release and yield issues related to stamen retention16. The seed yield for this operation was 2.4%, at least half that of other commercial eucalypts. When searching for collectable Box‐Ironbark seed crops, key factors to be considered are (summarised from section 3.2.1): 1. Capsule crops may prove difficult to find, requiring extensive field observation and ground‐based searching, as budding and flowering, which would allow forecasting, is not formally monitored. Crops will be patchy within the landscape, even following heavy flowering years. 2. Flower crops in E. tricarpa frequently fail to produce seed or only produce light seed crops. Heavy E. tricarpa seed crops can only be expected every four to seven years. 3. Box‐Ironbark species are concordant in relation to intensity of season; that is, all species will likely flower heavily in a high intensity flowering year, but this will still vary spatially. 4. More than 30% of capsules may not release seed during extraction, due to the retention of stamens and the often associated accumulation of web material that covers the capsule valves.

3.2.5 Seed viability, vitality, dormancy and susceptibility to heat Average number of viable seeds per E. tricarpa capsule was 3.3 from 715 capsules (Orscheg 2011), while Grose and Zimmer (1958b) reported average viable seeds per

16 These financial risks cannot be carried by private industry until the cost of collecting and extracting E. tricarpa is better known and understood.

58 Box‐Ironbark Silviculture Reference Manual capsule for E. sideroxylon* of 2.6 with a range 2.0 ‐ 3.7, and E. leucoxylon averaged 2.4 with the range 2.3 ‐ 2.6. Harwood et al. (2001) indicated approximately 5.0 viable seeds per capsule for E. tricarpa, the same as Dexter (1960) who noted a large range of 0‐23. Grose and Zimmer (1958b) also reported average viable seeds per capsule of 2.8 for both E. melliodora and E. polyanthemos. Although capsules of these species are smaller, seed is also smaller. Note that the number of viable seeds per capsule will be influenced by pollination factors, such as level of out‐crossing, which in turn is influenced by flower crop synchrony between trees and the resulting level of inbreeding depression (see section 3.2.1). Seed viability of a seed lot, however, has more operational relevance than seeds per capsule, being a measure of seed lot performance indicated by numbers of viable seeds per kilogram weight of seed (vs/kg). Viability increases for at least 12‐15 months following flowering, particularly for first year capsules (Bassett 2014). It may be related to the time of flowering, which can be particularly variable for E. tricarpa and E. leucoxylon (Keatley 1999; section 3.2.1). Viability can vary widely on the same tree within the year of flowering due to variation in fertilisation and insect infestation. Average viability figures for Box‐Ironbark species are given in Table 9. These are examples only, so it is critical that each seed lot first undergoes a formal laboratory germination test (Wallace & Fagg 1995), and that the results of the test be used to confirm maturity and set field sowing rates17. Maturity is indicated by estimating ‘seed vitality’, also known as ‘germination energy’. Viability measures should always be accompanied by estimates of vitality, and these can be determined in the one germination test. Vitality is measured by speed and completeness of germination. Although viability does increase toward maturity, it is possible for an immature seed lot to exceed a minimum target viability but still have low vitality. By definition, immature seed will have low vitality and may not perform well in field conditions (refer to NFSG 1 and NFSG 4). In general, Box‐Ironbark species do not exhibit seed dormancy nor induced dormancy (e.g. Dexter 1960 regarding E. tricarpa), but Larson (1965) found occasional dormancy in seed of E. microcarpa. However, this was classified as likely to be a secondary dormancy induced accidentally during collection or extraction, and is unlikely to have any operational implications. Cold stratification prior to germination testing is therefore generally not required.

17 At the time of publishing, VicForests offered a commercial seed testing service at its Noojee‐ based laboratory.

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Table 9. Average number of viable seeds per kilogram (kg) of seed# for nine Box‐Ironbark Eucalyptus species. Numbers of tests are in parenthesis.

Average no. of viable seeds per kg of seed Eucalypt species Boland et al. (1980) *DAR 2002‐2010 E. tricarpa (Red Ironbark) 225,000 (6) E. sideroxylon (Mugga Ironbark) 226,000 (26) E. leucoxylon (Yellow Gum) subsp. pruinosa 188,000 (17) E. leucoxylon (Yellow Gum) subsp. leucoxylon 235,000 (22) E. polyanthemos (Red Box) 465,000 (8) 362,000 (13) E. melliodora (Yellow Box) 352,000 (15) 293,000 (12) E. microcarpa (Grey Box) 777,000 (16) E. goniocalyx (Long‐leaved Box) 113,000 (7) 168,000 (9) E. macrorhyncha (Red Stringybark) 73,000 (11) 56,000 (30)

* DAR figures from DEPI (Lisa North pers. comm.) # mixed viable seed and chaff

Most Box‐Ironbark eucalypt species listed in Table 9 have an ideal (laboratory) germination temperature of about 25 oC, except E. tricarpa (20oC), E. sideroxylon (20 oC), and E. macrorhyncha (15 oC), although Boland et al. (1980) noted that a range of temperatures have not been properly evaluated for most of these species. E. tricarpa is reported by Dexter (1960) to have an optimum germination temperature of 26 oC. This temperature disparity may not be an issue for seed testing, but may help understand field trial results where climate variables are measured. These temperatures indicate that autumn and spring would be suitable for field germination, although autumn germination would give a greater time for seedling establishment prior to the first summer. In laboratory conditions, Dexter (1960) tested the effect of raised temperatures on the germination of fully imbibed E. tricarpa seeds. He found no significant difference between keeping the seed at 34 oC for four hours (before germinating at 27 oC) and no treatment. Grose and Zimmer (1957) tested the light requirements during germination testing of Victorian eucalypt species at 16 oC. E. leucoxylon, E. melliodora and E. macrorhyncha had no specific requirement for light. However, replicates of E. tricarpa did not exhibit the same outcomes, with the conclusion that continuous light is less suitable for

60 Box‐Ironbark Silviculture Reference Manual germination of some seed lots than continuous darkness, a point that may be relevant when testing this species. 3.3 Factors affecting seedling establishment Dexter (1960) described the long standing problem of achieving seedling regeneration in Box‐Ironbark forests. The issue was noted for E. tricarpa as early as at least the 1930s (Ferguson 1934). These and subsequent reports have recognised the need for some seedling regeneration, even though coppice regeneration is usually successful (Kellas 1991). However, coppice is not successful from 100% of cut stumps (see section 3.1.3). Therefore, occasional seedling recruitment is required to maintain stocking at the carrying capacity of the site, including in gaps that may have widened due to harvesting over time (Forest Solutions 2013). 3.3.1 Seed survival and protection Andersen (1987) showed that many species of ants harvest fallen eucalypt seeds in dry sclerophyll forests; the seeds were taken by species of the genera Anonychomymra, Iridomyrmex, Rhytidoponera, Pheidole and Chelaner. Using special trays (each with 50 E. tricarpa seeds) set on the ground near Whroo (Rushworth district), Dexter (1960) found high percentages of seeds (23‐100%) removed in each of the months April to July. Most losses were attributed to harvesting by ants, as when an insecticide seed coating was used, seed losses were minimal. Seeds (from natural seedfall or artificial sowing) which do not germinate in the field for any reason and are not harvested by ants (estimated at up to 80%) probably die within 12 to 18 months due to fungal activity (Campbell et al. 1984). For many years the Forests Commission of Victoria used insecticides and fungicides together with kaolin and mucilage to coat seeds which were to be artificially applied to seedbeds. However, some of these ingredients were found to inhibit germination (Neumann & Kassaby 1986). Currently, most seed is sown raw and uncoated (Fagg 2001), although an effective alternative coating with no chemicals was discovered (Roberts 2001) and is valuable for use in hand‐sowing. A light covering of soil over sown seed should reduce predation by seed harvesting insects (Ashton 2000) and is essential for germination. While this happens naturally in more friable soils, where the soil surface is hard and sealed and surface humus is limited (as in many Box‐Ironbark areas), most seed remains vulnerable to insects. 3.3.2 Timing of sowing/seedfall, and germination Like other lower elevation forests, seed in Box‐Ironbark forests can be expected to germinate at any time of the year when temperature and moisture conditions are

Box‐Ironbark Silviculture Reference Manual 61 suitable. Due to seasonal variation there will be peaks of germination in autumn and spring, and minimal germination in summer (too dry or hot) and winter (too cold). However, some seedlings which germinate in autumn may be killed by severe frosts in the following winter, while spring germination can be exposed to heat and soil drought as well as late frosts. Orscheg (2011) inexplicably observed nil germination after sowing in May (x 2 years), August (x 2) and October (x 1), but after sowing in early July, Dexter (1960) obtained germinants from 2.5% of seeds sown, somewhat lower than other eastern Victoria commercial species (4%). Seedfall in E. tricarpa occurs naturally in the period December to March, with a peak from late February to mid‐March (see section 3.2.3). This indicates that this species is best artificially sown in early autumn, or that seedbeds should be prepared by early autumn to receive natural seedfall. This autumn timing led to good regeneration obtained by sap‐ringing seed trees to induce seedfall soon after slash burning in mid‐ March (Ferguson 1934). In years of average rainfall, however, it is probably best to wait until April to sow collected seed. See section 6 for recommended target densities and sowing rates when sowing. In summary, artificial sowing (on a suitable seedbed) in the period April‐June can be expected to yield the best seedling establishment, given average rainfall, although soil moisture will be affected by the level of retained overwood. 3.3.3 Seedbed type and competition Ferguson (1934) found that good seedling development was almost entirely confined to ashbeds where logs, bark or branches had been burned prior to induced seedfall; areas of light ash or unburnt patches had no seedlings. Similarly, artificial sowing by De xter (1960) was only successful on ashbeds. A severe bushfire burnt large areas of Box‐Ironbark forest near Maryborough in January 1985 (see section 2.2.1). By 1992 many seedlings (40‐50 cm tall) were clearly struggling under overwood that was recovering strongly via stem epicormics (P. Fagg, pers. obs.). Seedlings dug up had well‐developed lignotubers, (Figure 16) but over time few survived due to the strong competition for the limited soil moisture. Competition for light and moisture was also evident in a trial to regenerate E. drepanophylla (Queensland Grey Ironbark) in a moist mixed species forest (Florence 1996). Excellent seedling regeneration occurred from induced natural seedfall on ashbeds in gaps, but most died due to competition from vigorous fire‐successional species, advance growth and coppice, and residual overstorey. The unburnt, mineral soil seedbeds used by Orscheg (2011) ‐ even a seedbed created by rotary‐hoeing to a depth of 10 cm ‐ resulted in no seedling regeneration, for unknown

62 Box‐Ironbark Silviculture Reference Manual reasons. Uncontrolled variables included seed predation (found to be high in this forest type by Dexter 1960), browsing and more seasonal variation. As such, undertaking this trial in another decade may have produced different results. In Messmate‐Peppermint forest in the Wombat Forest near Daylesford, Kellas (1994) found that there was a tendency for seedbed type to influence the type of germinant mortality, with the drought‐induced symptoms following frost damage less frequent on burnt seedbed (23%) than on mineral soil seedbeds (33‐37%). Kellas also recorded seedling percents of seven, three and five respectively under zero, 10 and 15 m2/ha of retained overwood. This pattern of survival, decreasing with increasing residual basal area, resulted from increased shading and competition for soil moisture. In Box‐Ironbark stands, competition for soil moisture, rather than shading, would be expected to be very high, due to relatively low rainfall, high summer precipitation and higher temperatures, especially in late spring and summer. In summary, ashbeds appear to be favourable seedbeds, but unless potential competition from overwood or coppice regrowth is minimised, the seedlings are unlikely to reach even a regrowth stage. Practically, creation of adequate ashbeds in many harvested Box‐Ironbark stands with relatively small amounts of fuel is difficult, and mechanical soil disturbance will often be required. Refer to section 6 for recommendations for different silvicultural systems. 3.3.4 Frost and fire Severe frosts (<0.0 oC) occur occasionally in July and August, but the frequency varies widely from year to year (see section 1.4). Tree canopies can modify ground temperatures, so it is likely that there are fewer severe frosts within stands. Frost damage to small seedlings by frost heave and tissue freezing is usually less on ashbeds (Kellas 1994). Overall, frost damage in Box‐Ironbark forests is probably not a major factor in affecting seedling establishment in most years, although field studies are needed to verify this. Fire can directly kill seedling regeneration, seriously alter the form of any survivors and remove important surface humus, resulting in further impoverished soil. Accordingly, fuel reduction burns must be planned to minimise any chance of damaging recently established seedlings or young regrowth.

3.3.5 Browsing animals Browsing animals can have a significant impact on seedling and coppice establishment in some Box‐Ironbark forests. In a State‐wide survey, Wallace and Fagg (1999) found that in Box‐Ironbark forests, severe browsing of small regrowth occurred only on 3% of coupes. The most significant browsing species is the native Swamp Wallaby (Wallabia bicolor), followed by the introduced European Rabbit (Oryctolagus cuniculus). It is likely

Box‐Ironbark Silviculture Reference Manual 63 that both these species, which are widespread in the Box‐Ironbark forests and woodlands, are involved where significant damage occurs. Within Victoria, the only currently available and fully effective means of preventing or controlling browsing damage to regenerating coupes on public land is suitable fencing. Further information relating to the management (particularly the assessment of browsing risk and damage) and control techniques can be found in Native Forest Silviculture Guideline No. 7 Browsing Management (Poynter & Fagg 2005) and the proceedings from a national workshop on forest browsing held in 1999 in south‐ western Victoria (NRE 2002). 3.4 Stand and tree growth 3.4.1 Growth rates Based on growth ring analyses of samples from 852 trees covering a range of Box‐ Ironbark eucalypt species, in thinned and unthinned stands throughout the Bendigo FMA, annual average diameter growth rates were found to be 3.2 mm and 3.8 mm in southern and northern districts respectively (NRE 1998). However, following some doubt as to the accuracy of determining annual rings in the main species, re‐ measurement in 2000 of nearly 200 trees resulted in lower diameter growth estimates; 2.1 mm/yr in the south and 2.4 mm/yr in the north. These figures were used in calculating sustainable harvest limits as reported in Forest Solutions (2013). Based on a 2.4 mm/yr rate, a tree of 40 cm DBHOB would therefore be about 165 years old, but the same size tree would be 110 years old based on a 3.5 mm/yr growth rate. A report by Kellas et al. (1998) measured increment on trees subjected to different degrees of release over a 23‐year period (1972‐1995) between 2.1 and 4.6 mm/yr for regrowth (<20 cm DBHOB), and 3.4‐5.5 mm/yr for the overwood. Response of the regrowth to reduction in competition was rapid when overwood was removed, and was further enhanced if the regrowth was thinned out. Newman (1961) recorded mean annual volume increment of 60 year old Box‐Ironbark regrowth of 0.8‐1.5 m3/ha/yr. In terms of sawlogs (Grade 1 + Grade 2 ‐ see Appendix C), average yield over the total Bendigo FMA was estimated at 3.2 m3/ha over 72,300 ha of available forest area (Table 3, Forest Solutions 2013), but varied widely with working circle. Note that this figure is not the same as the MAI (mean annual increment rate). 3.4.2 Growth response to thinning After a stand is thinned, retained trees will grow to a given size in a shorter period of time, or will grow to a larger size in any given time, compared with an unthinned stand

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(Fagg & Bates 2009). The duration of the response after thinning increases with the intensity of thinning and decreases as the age at which thinning is carried out increases. Kellas et al. (1982) showed that removal of competing Box‐Ironbark coppice stems can increase basal area (BA) increment of retained stems by at least 25%. This 8‐year study (undertaken 1972‐1980, near Heathcote) showed that two steps were needed to accelerate annual BA growth of regrowth from 0.5 m2/ha to 0.8 m2/ha: 1. significant reduction of any overwood (but retaining necessary habitat trees) 2. thinning (from below) at least 50% of the basal area of the regrowth.

A later trial in a uniform plantation E. tricarpa at Dargile with no overwood showed that 67% BA removal was required to achieve a significant BA response (Murphy & Forrester 2008). In addition, post‐thinning coppice control led to significant extra growth in the 100 largest retained trees per hectare (Table 10), as the stumps of newly felled trees will almost always sprout (coppice) and compete strongly for soil moisture. In the case of this trial, coppice was manually cut or knocked off the stumps, but herbicide treatment of cut stumps or coppice foliage may be more cost‐effective in the long run, unless flash‐back was found to be a problem.

Table 10. Basal area (BA) response of the 100 largest trees per ha (from Murphy & Forrester 2008).

% of initial BA Coppice control? Mean* BA at 10 years retained after thinning (m2/ha) 33 yes 9.6 c 33 no 9.1 b 50 yes 8.8 a 60 no 8.6 a 100 (control) n/a 8.4 a *means with different letters are significantly different

Although the stand in this study was not typical for most Box‐Ironbark regrowth in that it was relatively old and closely spaced when thinned, the result indicates that a heavy thinning is needed to get a measureable response. Analysis of the total stand BA showed no significant differences, indicating that retained smaller trees did not respond as well as the 100 larger ones. Moderate to heavy thinning may reduce the ultimate height growth of the retained trees, as the tree tends to extend its crown sideways rather than upwards. Therefore, for thinning in Box‐Ironbark, the stand selection criteria require that the clear bole be at

Box‐Ironbark Silviculture Reference Manual 65 least four metres on dominants and co‐dominants trees before commercial thinning is considered (see Table 14). 3.4.3 Branch and crown development Jacobs (1955) describes two general types of eucalypt crown:

 The primary crown, which develops directly from the buds in the leaf axils; these determine the overall height growth and crown shape.  The secondary crown, which develops from dormant buds, often in the form of epicormic shoots following fire damage.

Stages in the development of the tree crown are as follows: In young seedlings the leaves are borne directly on the main stem and are either arranged in pairs opposite each other or alternately along the stem. Once the seedling reaches more than about 60 cm high, branching commences and vigorous height growth occurs through the sapling stage. This stage is characterised by a crown of small branches which self‐prune as the tree gains height and results in a clear bole. At the pole size, the larger branches persist for a longer period but are still inferior to the apical section of the stem. As the tree nears maturity the tree loses its pole form and develops larger and persistent branches. Branches at this time grow from both the main trunk and from the large branches that form the framework of the crown. Eucalypts also develop ‘crown shyness’ so that overlapping or touching crowns are rare due to the sensitivity of the naked buds in the crown to abrasion from adjacent crowns (Jacobs 1955). Crown size determines potential flower and seed crop quantities. For some East Gippsland eucalypt species, Bassett et al. (2006) found that seed crop sizes were related to crown size or the number of potentially seed‐bearing (2 cm diameter) branchlets, which was strongly correlated with bole diameter. This is a principle which is likely to also apply to Box‐Ironbark species. 3.4.4 Root and mycorrhizae development The roots in young eucalypt seedlings and saplings have a vertical (tap root) development with few laterals, but as the tree matures the lateral root system with secondary roots becomes dominant (Florence 1996, drawing on Jacobs 1955). Studying tree development in the Wombat State Forest, Weir (1969) found that most roots were located within the top 30 cm of soil in relatively skeletal soils (not unlike

66 Box‐Ironbark Silviculture Reference Manual many of the Box‐Ironbark soils), and concluded that the depth of the ‘A’ horizon was important in determining the rooting pattern of the regrowth stems. Vitally important to the nutrition of most eucalypts are ectomycorrhizae, which are symbiotic associations of fungi with tree roots; fungal tissue forms sheaths around the fine lateral roots, often with a distinctive pinnate habit. Over 150 fungal species in over 60 genera are believed to be ectomycorrhizal with eucalypts (Chilvers 2000). These ectomycorrhizae enhance the absorption of nutrients from soil, particularly phosphorus, from soil (Grove et al. 1996) and increase the resistance of trees to environmental stress. Optimal conditions for mycorrhizal formation are moderate soil water potentials in which fine soil pores contain water and larger pores are air‐filled. In very dry soils the abundance of mycorrhizae is greatly reduced (Chilvers 2000). Mycorrhizae are most effective in increasing the growth of eucalypts in soils which are deficient in phosphorus and nitrogen (Bougher et al. 1990). The extent of the occurrence of mycorrhizae in Box‐ Ironbark species and sites is unknown, but it is confidently assumed that they do occur.

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4. Selection of silvicultural systems 4.1 Strategic planning Timber utilisation and the associated silvicultural systems are linked to relevant forest management objectives (as detailed below). In State forest, these objectives are based on State government policies on natural resource management, such as the Timber Industry Action Plan (DPI 2011), Regional Forest Agreements and Forest Management Plans. In Victoria, there is a Forest Management Plan for each of the 14 Forest Management Areas. These plans delineate three types of usage or management zones within State forest, as follows: 1. Special Protection Zones (SPZ) ‐ have particular conservation values that are incompatible with timber harvesting. SPZs form a network designed to complement the formal conservation reserve system. 2. Special Management Zones (SMZ) ‐ have certain conservation values, but timber harvesting may be permitted under special conditions specified in SMZ plans. 3. General Management Zones (GMZ) ‐ are managed for a range of uses and values, but timber harvesting will have a high priority. Effective community engagement is needed to establish the right balance of conservation and timber production and to optimise the triple ‘bottom line’ of social, economic and environmental factors. This applies both to the strategic planning phase, such as to Forest Management Plans for FMAs, and to the more short‐term, local Wood Utilisation Plans. To ensure minimal environmental impact, all timber harvesting must comply with the Code of Practice for Timber Production (DSE 2014a)18 and any specific prescriptions and guidelines which are applicable to the location in question. 4.2 Silvicultural systems for different objectives ‘Silvicultural system’ is a term that describes the techniques and their timing used to manage harvesting, re‐establishment and tending of a stand or forest through one life cycle. Silvicultural systems are often named according to the type and intensity of the harvesting phase.

18 The 2007 Code was revised by DEPI during 2013 and 2014.

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Choosing the most appropriate silvicultural system for a particular stand of trees or proposed coupe, requires consideration of:  the main objective or relative priorities of management (e.g. wood production, flora and fauna conservation, nectar production.  site factors (e.g. tree age/size class distribution, forest structure, seed availability, terrain)  commercial factors (e.g. markets for the products, availability and skill of harvesting crews, and cost of supervision)  management prescriptions and regulations (e.g. those that conserve wildlife habitat, such as Special Protection Zones and nesting tree restrictions). The choice of system may often be a compromise between the desirable outcome from a silviculture viewpoint and the economic and social realities of the operation. A useful concept or principle is that of ‘ecological forestry’, in which silviculture “should consider, and, as far as practicable work within the limits of, natural disturbance patterns that existed before extensive human alteration to the landscape” (Stoneman 2007). In general, the simpler the system the easier it will be to implement. Conversely, the more complex the silvicultural system, the more difficult and costly it will be to implement. For a detailed summary of the development of native forest silviculture over recent decades in Victoria, refer to Lutze et al. (1999). The long utilisation history of most Box‐Ironbark State forests and the fact that most cut stumps re‐sprout (i.e. coppice) means that most areas of the forest will contain trees of a range of ages (i.e. uneven‐aged) and sizes. This makes the forest amenable for ‘selection’ silviculture; that is, removing only the trees which are large and sound enough for sawlogs and leaving the rest. Where the forest or stand is relatively young, that is, ‘regrowth’, ‘thinning (from below)’ is an appropriate system. ‘Coppice with standards’ is the term used for a stand that has a mixture of selection harvesting and thinning ‐ as described later. All of these systems can be described as ‘continuous‐ cover’ silvicultural systems (Kimmins 1997, Florence 1996) as they maintain a tree canopy over most of a site continuously in terms of both time and space, unlike, for example, a ‘clear‐felling’ system. In contrast to most low elevation mixed species forests (Murphy et al. 2013), the even‐ aged clear‐felling or seed tree systems would rarely be applicable in Box‐Ironbark forests. The only possible situation could be where forest was severely burnt by a bushfire and heavy felling was deemed necessary to salvage the damaged timber. These even‐aged systems are not covered in this manual.

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The flow chart representing the Silviculture Decision Support System (SDSS) for Box‐ Ironbark (Appendix D) has been prepared to assist in the selection of silvicultural systems (see section 4.3). Tables 11 and 12 give rankings for five possible silvicultural systems that can be used in Victorian Box‐Ironbark forests. These aim to show how well each system would meet both the main desired management objectives and the main operational issues, respectively. These systems and how they are implemented are described in Chapter 5. Generally, the system chosen will be a result of balancing competing demands.

Table 11. Relative effectiveness of alternative silvicultural systems in meeting different management objectives in Box‐Ironbark forests. Ranking: 1 star‐ very low, 5 stars‐ very high

Main Objective Single Group Coppice Thinning Thinning Tree Selection with (commercial) (ecological) Selection Standards Landscape/recreation ***** **** *** **** *** Timber production *** *** **** **** ** Fauna conservation ***** **** **** *** **** Flora conservation **** **** *** *** **** Nectar production **** *** **** *** *** Note ‐ Wherever timber harvesting is carried out the Code of Practice requires that non‐timber values will be protected as far as practicable.

Table 12. Relative effectiveness of alternative silvicultural systems in meeting different operational objectives in Box‐Ironbark forests. Ranking: 1 star‐ very unfavourable, 5 stars‐ very favourable

Main Objective Single Tree Group Coppice Thinning Thinning Selection Selection with (commercial) (ecological) Standards Costs to contractors (harvesting, haulage, *** **** **** ***** ** etc.) Costs to forest manager (planning, **** *** *** ** ** supervision, etc.) Safety of harvesting ** *** **** ** *** operations Quality and quantity of *** **** *** n/a n/a regeneration Fire risks & protection **** *** *** ** **

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All silvicultural systems potentially applicable to Box‐Ironbark forests rank relatively well for all main management objectives, because they maintain an essentially continuous canopy cover throughout the cutting cycle and rotation.

All silvicultural systems potentially applicable to Box‐Ironbark forests rank relatively well for all main operational objectives, because of the relatively low density and height of the forests, and because regeneration via coppice is very reliable. 4.2.1 Timber production Compared with even‐aged silvicultural systems (not shown in Tables 11 and 12), there are increased operational costs associated with selection (or uneven‐aged) systems. For example, for a given volume of wood production from multiple, scattered, small gaps (group selection), there is a need for more tree marking and use of more of the road network for access, when compared with simpler harvesting systems such as the seed tree system. Additionally, the greater ‘edge effect’ associated with the small gaps of group selection (Wang et al. 2008) will suppress growth rates of regeneration and older regrowth, compared with more intensive silvicultural systems (Bassett & White 2001). Nevertheless, selection and thinning systems have advantages over other systems where conservation and/or aesthetics rate at least as important as wood production. Importantly, selection systems are more appropriate where the forest structure is already uneven‐aged, as are most of the Box‐Ironbark forests. Analysis of Victorian Box‐Ironbark State forest in the five year period to 2000/01 (Table 15 in Fagg et al. 2008), showed that an excellent 95% of the surveyed coupe area was satisfactorily stocked after harvesting using selection systems. Regarding browsing damage, selection and thinning systems have a relatively high risk, because they produce localised patches of young regrowth (mainly coppice), which are attractive to resident browsing animals such as Swamp Wallabies. The overall level of environmental impact of timber harvesting can be considered as the combination of the coupe‐level impacts with the landscape‐level impacts, such as proportion of forest harvested each year, and the time cycle for successive harvesting and regeneration operations. 4.2.2 Water production Water is a valuable and essential commodity, and the best quality water comes from forested catchments with restrictions on human entry. Although disturbance caused by timber harvesting in water catchments has the potential to reduce water quality, it is

Box‐Ironbark Silviculture Reference Manual 71 well known that tree harvesting may lead to increased water yield by temporarily reducing the forest’s use of water from the soil. This is primarily achieved by reducing tree densities through harvesting, including thinning. In mixed eucalypt species, thinning results in a short‐term (8‐10 years) increase in water yield from the coupe. No such catchment studies have been carried out in Box‐Ironbark forests, but because these forests occur in warmer and lower rainfall areas than mixed species forests, any effect is expected to be less. It is notable that Western Australia is implementing a 12‐year, $20 million research trial in the Wungong catchment which supplies water to Perth. This is based on a study that reported a substantial increase in water yield after thinning catchments forested with E. marginata (Jarrah) (Bari & Ruprecht 2003) which has ecological similarities to Box‐ Ironbark. They showed that the effect decayed after about five years and returned to pre‐thinning levels after about 12 years as the retained trees and regrowth increased their water usage. The current trial is aiming to test the assumption that the catchment treatments will produce extra and more economical water than water from bores or desalination of sea water (Batini et al. 2007). 4.2.3 Nectar/honey production Table 11 indicates that all silvicultural systems appropriate for Box‐Ironbark forests are satisfactory for continuous nectar production The Management Procedures (DEPI 2014c) state at 4.5.1, regarding the Bendigo FMA: “When planning harvesting in patches of summer‐flowering Red Ironbark stands, ensure that potential short‐term flowering reductions resulting from harvesting are not concentrated in time or location”. 4.2.4 Flora and fauna conservation Within the main Box‐Ironbark forest area as whole (central and north‐eastern Victoria), about 43% is permanently reserved for conservation purposes (ECC 2001), compared with about 28% reserved as State forests. Within State forests, the Special Protection and Special Management Zones (see section 4.1) are primarily intended to focus on the conservation of flora, fauna and landscape values. However, these values must also be considered when timber harvesting in the General Management Zone, as documented in the Code of Practice (DEPI 2014b) and the associated Management Standards and Procedures (DEPI 2014c). Studies (see section 2.1.2) have demonstrated that species requiring hollows, such as forest owls and gliders, need substantial areas of older forest to survive and are sensitive to forestry practices which remove old trees. Group and single tree selection

72 Box‐Ironbark Silviculture Reference Manual silvicultural systems, by retaining permanent tree cover and a range of age classes over a rotation, are inherently more favourable in supporting populations of animal species (Loyn 2004). Prescriptions for habitat retention (see Appendix E) in State forests are aimed at retaining suitable frequencies of larger trees as habitat, and where larger trees do not occur, numbers of smaller trees must be retained for future potential habitat trees. Kutt et al. (1995) and Kutt (1994), reporting on the initial impacts of thinning for mixed species in East Gippsland, found that regrowth (and some types of old forest) supported low populations of most possums and gliders (compared with old forest), concluding that thinning of regrowth trees as such would not disadvantage any species. This finding is supported by extensive Box‐Ironbark survey data which showed that trees less than 20 cm DBHOB effectively lack hollows, and that 20‐40 cm DBHOB trees have very few hollows (NRE 1999). Adkins et al. (2005) examined the effect of fire on hollow formation in Box‐Ironbark eucalypts in north east Victoria, concluding that tree size, rather than fire per se, influenced the quantity of dead branches and branch stubs on a tree. For a summary of the main findings for the indicators (for the seven Montreal Process criteria) used to assess sustainable forest management in Victoria, see DEPI (2014a). The first criterion, ‘conservation of biological diversity’, relates directly to flora and fauna conservation. 4.2.5 Landscape management Public perception of harvested areas is often negative. In a Tasmanian study, Ford et al. (2009) measured the social acceptability of different harvest and regeneration systems by individual people, using still and animated images. On average, non‐affiliated and conservation affiliated people rated the clear‐felling system least acceptable and a selective harvesting system most acceptable. In the Box‐Ironbark forests, where selective felling is the normal type of silviculture, serious criticism of harvesting based on landscape or aesthetic reasons is infrequent.

4.3 Decision support systems A Silviculture Decision Support System (SDSS) provides a methodology for the silvicultural management of a range of forest stands. An SDSS is constructed as a flow chart around a series of decision points (DPs) and associated actions that are based on the monitoring of different factors. Focusing only on uneven‐aged silvicultural systems, the Box‐Ironbark SDSS flow chart (Appendix D with explanatory notes) is designed to be attached to the Coupe Plan to

Box‐Ironbark Silviculture Reference Manual 73 provide a record of both the intended or amended operations ‘path’, and covers the following operational stages:  Planning  Harvesting  Monitoring  Regeneration ‐ site preparation ‐ coppice/seedling establishment  Monitoring and recording.

The silvicultural system options in the uneven‐aged/regrowth SDSS are ‘thinning’, ‘single tree’ or ‘group selection’ and ‘coppice with standards’, depending on the relative amounts of basal area of different stand components. Options for seedbed preparation methods, where seedling regeneration is required, include:  slash burning  soil disturbance, in addition to that created by harvesting.

4.4 To salvage or not to salvage? While damaging fires in Box‐Ironbark forests are not common, they do occur. Where fire intensity is severe, some Box‐Ironbark stands may be damaged enough for at least partial timber salvage to be considered, (possibly using selection silvicultural systems) even though most trees will always survive due to stem epicormic regrowth (see more information on the effect of fire in section 2.2.1.) NFSG 17 Forest Recovery after Bushfire (Poynter et al. 2009) will assist with resolving how to assess and treat fire‐damaged stands. With non‐ash eucalypt species it is preferable to wait at least 12‐18 months after the fire to observe the extent of recovery before making any decision to salvage harvest or not. Although periodic insect plagues will also defoliate trees in Box‐Ironbark forests, the trees will invariably recover, usually within 12 months, and thus salvage need not be considered. If the fire has caused natural seedling regeneration to become established, care must be taken during any log salvage operations to minimise damage to such seedlings, as well as adhering to the Code of Practice (DEPI 2014a). Sometimes, more common than fire salvage, is salvage of timber in wind‐thrown trees which have come down during storms. Clearly, such trees will not recover.

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5. Silvicultural systems and practices

This Chapter describes silvicultural systems which are currently used in the Box‐ Ironbark forest type. Briefly, a ‘silvicultural system’ describes the techniques used to harvest, regenerate and tend a stand of trees through one life cycle (rotation). The selection and thinning systems are also applicable to plantations of E. cladocalyx (Sugar Gum) which are common in parts of western Victoria (Forest Solutions 2013). This species (native to South Australia) grows in similar soil types as Box‐Ironbark and also coppices strongly. As described in Chapter 3, all common eucalypt species in Box‐Ironbark forests naturally produce coppice from cut stumps. This feature ensures that harvested areas usually regenerate themselves, without the need for relying on seed to germinate and produce seedlings. The Silviculture Decision Support System (SDSS) (see section 4.3 and Appendix D) should be employed to assist in the choice of the silvicultural system best suited to the stand or coupe, based on existing stand size/age structure, basal area and products being sought. In terms of planning, and prior to any harvesting, a Forest Coupe Plan, including a detailed site map with the coupe boundary, is required for each specific timber harvesting operation. It is prepared after the proposed forest area is inspected and assessed, and must accord with the Code of Practice (DEPI 2014b) and associated environmental prescriptions and guidelines (DEPI 2014c). These are designed to protect soils and water quality, and to maintain satisfactory native animal habitat. In addition, any special conditions, such as those specified in Flora and Fauna Action Plans to protect rare or threatened plants or animals must be taken account of in the coupe planning process. The Coupe Plan must also document the Reference Basal Area (RBA) (see Table 7 in NFSG 10), the silvicultural system to be employed (one of the systems described below) and the proposed regeneration process. The SDSS flow chart should be attached to the Coupe Plan in order to provide a visual record of both the intended or amended operations ‘path’.

5.1 Single tree selection 5.1.1 Description Single Tree Selection (STS) involves the removal of individual scattered trees which meet the sawlog specifications, at intervals of 15‐30 years, repeated indefinitely. Via coppice, the stand is regenerated more or less continuously and an uneven‐aged stand results. Some seedling regeneration may be required to maintain stocking, but not after

Box‐Ironbark Silviculture Reference Manual 75 every removal. This system has been successfully used for many decades in the Box‐ Ironbark forest type (Kellas 1991, Figure 23). Note that where quality coppice is present, both sawlogs and coppice can be treated using the Coppice with Standards system (section 5.3 and SDSS in Appendix D). 5.1.2 Marking and harvesting Prior to harvesting, the largest or dominant trees (but less than 60 cm DBHOB) are selected and marked (by paint on the trunk and below stump height) for removal. The selected trees must meet the current minimum specification for sawlogs ‐ mainly Grade 1 (see Appendix C). The number of trees that may be harvested per hectare is not fixed, but varies according to the site quality (or growth potential), the time since the previous felling and the numbers of habitat trees required to be retained (Figure 17).

Figure 23. (a) An E. tricarpa tree harvested during a Single Tree Selection operation in 2012. Note the stump (foreground) and residual bark and head material (background). The log has been removed. (b) An E. tricarpa habitat tree retained during Selection harvesting in 1997. Both images in Rushworth State forest.

However, in most cases, the basal area should not be reduced below 40% of the original basal area, so that adequate stocking remains on the coupe (NFSG 10). The Regeneration Standard in NFSG 10 also recommends keeping the proportion of retained

76 Box‐Ironbark Silviculture Reference Manual basal area that is non‐merchantable to below 7%. If this cannot be achieved, forest quality and future commercial viability is an issue. Action to improve stand quality in this scenario could include the removal of non‐merchantable stems to create gaps ready for seedling regeneration (refer to section 5.2). In the process of marking sawlog trees, sufficient numbers of ‘habitat trees’ and any trees over 60 cm DBHOB, must be identified and painted with an ‘H’ before harvesting commences. Appendix E gives the current habitat specifications. Trees with >20% mistletoe infestation in their crown are usually marked for removal. The harvesting must be conducted in a way that minimises damage to any retained trees. Currently, a typical operation involves hand‐falling using chainsaws, followed by agricultural‐type tractors to drag the logs to a landing or a truck. Logs are then loaded on to tray trucks using winching systems. 5.1.3 Site preparation No ground or soil treatment is required to create a seedbed. 5.1.4 Regeneration and its protection Usually, no specific steps to obtain regeneration will be required, as most cut stumps will coppice. However, cutting stumps to a maximum height of 30 cm is within the prescription (DEPI 2014c) and vital to maximise the chances of coppice fixing securely to the stump. Planned fuel reduction burning (FRB) and unplanned fire is probably the main threat to young coppice regeneration. Sustainability of tree cover and timber production is at risk if burning occurs before coppice is large enough to withstand fire. Close liaison with staff responsible for FRB and risk‐based burning should minimise fire damage. In some coupes, young coppice may be subject to browsing by wallabies, but usually, without specific protection measures, at least one stem on each stump will survive and grow outside the reach (~0.7 m) of wallabies. The semi‐parasitic vine Cassytha melantha (Coarse Dodder‐laurel) can damage and kill coppice by growing over it and essentially smothering it. Physically cutting off vines from the coppice has limited effectiveness, because small missed pieces can re‐grow (see section 2.2.2 for more information on the biology and control of C. melantha). 5.1.5 Performance measurement In Victorian State forests where selection silviculture is used, all coupes must be formally assessed in the period 18‐36 months after harvesting (NFSG 10 ‐ Bassett et al.

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2014a). In Box‐Ironbark coupes, however, the stocking survey could be done as soon as nine months after harvesting is completed, as coppice is usually established by then. The survey procedure is detailed in NFSG 10. It involves assessing both the standing trees and/or the regeneration (coppice and seedlings) on plots on a systematic grid over the coupe. A Regeneration Standard representing ‘industry best practice’ is recommended, including the following:  If the total basal area is greater than 40% of the Reference Basal Area, the plot is deemed ‘stocked’.  A plot may be also stocked if there is at least one acceptable sapling (or coppice or seedling) within a radius of 3.57 m centred on the grid point.  For a coupe to be declared satisfactorily stocked, a minimum of 75% of all survey plots must be stocked and no discrete area >2 ha must be unstocked. 5.1.6 Flora and fauna conservation Implementation of the habitat retention prescriptions will ensure adequate current and future tree habitat for birds and arboreal mammals; in STS coupes there will always be well‐developed trees covering most of the area. In the Bendigo Forest Management Area, all living E. melliodora (for honey production and the rare E. aromaphloia (Fryers Range Scent‐Bark) and E. tricarpa (Bealiba Ironbark ‐ a glaucous form), must be permanently retained, as per Appendix E. Coarse woody debris (CWD) larger than 40 cm diameter, with hollows larger than 10 cm diameter must be retained, as it can be important fauna habitat. In Special Management Zones, CWD levels must not be reduced below pre‐harvest levels.

5.2 Group selection 5.2.1 Description ‘Group Selection’ (GSE) involves removing/felling all trees in a patch of approximately 20‐30 metres in diameter or widening an existing small gap to this size. Products resulting from GSE are mainly Class 1 and 2 sawlogs plus firewood. GSE is rarely applied in Box‐Ironbark forests, but may be implemented where either: 1. bushfire or wind‐throw has caused severe damage to trees in patches and the trees are to be salvaged for timber 2. seedling regrowth is required in addition to coppice 3. existing seedlings/coppice need to be released from competition.

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This patch cutting is repeated within a coupe at intervals of 20‐30 years ‐ with the lower intervals on sites with better growth potential. For example, for a 120‐year rotation and a 20‐year felling cycle, a total of 1/6th (or 16%) of a particular coupe would be removed in each felling. Undertaking a stocking survey, either following a recent removal or to measure the frequency and stocking of gaps if they are suspected, can help identify where seedling regeneration is required, instead of coppice. 5.2.2 Marking and harvesting All (or most) trees <60cm DBHOB in the patch are selected and marked for removal. The majority of these trees should meet the current minimum specification for sawlogs ‐ either Grade 1 or Grade 2 (see Appendix C). In most cases the group/patch will also contain some trees which are either too small or too damaged (in the case of fire damage) to make sawlogs. These trees will be utilised as firewood. In the process of marking sawlog trees, sufficient numbers of ‘habitat trees’ to be retained (following Appendix E) must be identified and painted with an ‘H’ before harvesting commences. Harvesting must be conducted in a way that minimises damage to retained trees surrounding the gap created. NFSG 10 suggests maintaining stem damage to below 20% of retained basal area. 5.2.3 Site preparation Salvage coupe. No ground/soil treatment is required. Seedling promotion coupe. Where the aim is to obtain seedling growth in gaps, head burning of the slash (debris such as branches and bark left after the harvesting) is recommended in order to prepare a seedbed, as per NFSG 6 ‐ p.16 (Lutze & Geary 1998). If burning is not possible, mechanical disturbance (by ripping the soil to a depth of at least 20 cm) should be carried out. Releasing regrowth. No ground/soil treatment is required. 5.2.4 Regeneration and its protection Salvage coupe. Usually no specific steps to obtain regeneration will be required, as most cut stumps will coppice. Seedling‐promotion coupe. On ashbeds, spread collected raw seed at the rate of approximately 20 viable seeds per square metre and lightly cover the seeds by raking soil over them. For unburnt seedbeds, sow seed by hand to rip lines/furrows at the rate of approximately 20 seeds per lineal metre and lightly cover the seeds by raking soil

Box‐Ironbark Silviculture Reference Manual 79 over them19. This is a labour‐intensive procedure, but mechanisation is not justified on this small scale. The raw seed may be coated to bulk the lot and assist distribution, according to NFSG 5 Eucalypt Seed Coating (Roberts 2001). Otherwise, a suitable seed dispensing device is a jar with holes drilled in the metal top designed to release the required number of seeds when shaken, or use the Doyle Seeder (see NFSG 8 ‐pp. 16‐18 Fagg 2001). This artificial sowing may be complemented with slash seed and even with seedfall from mature trees surrounding the gap, if present. Regarding protection requirements, as described in section 5.1.4, fire is the main agent of damage to regeneration. This must be minimised. Coppice may be subject to browsing by Swamp Wallabies, but usually at least one stem on each stump will survive and grow outside their reach. Where the aim is to promote the establishment of seedlings, herbicide treatment of some coppice will probably be required to minimise competition (see section 5.4.3). Seedlings will likely need some form of protection from rabbits and wallabies. Firstly, ‘Browsing Indicator Plots’ can be set up, and later possibly ‘Browsing Indicator Transects’ could also be set up in the coupe (see NFSG 7 ‐ pp. 7‐9 Poynter & Fagg 2005). Depending on the results, browsing control may be required. Options described in NFSG 7 include fencing, tree guards and application of a repellent substance. For information on the control of the smothering vine Cassytha melantha (see section 2.2.2). 5.2.5 Performance measurement All coupes must be formally assessed in the period 18‐36 months after harvesting, according to NFSG 10. The procedure is as described above for Single Tree Selection. 5.2.6 Flora and fauna conservation The measures described under Single Tree Selection (see section 5.1.6) also apply to the Group Selection system.

5.3 Coppice with standards 5.3.1 Description A ‘Coppice with Standards’ (CWS) system is a special type of commercial thinning combined with single tree selection. Selected trees (arising from either seedlings or

19 Artificial sowing requires that seed be previously collected from suitable trees. See section 3.2 for seed collection and management techniques.

80 Box‐Ironbark Silviculture Reference Manual coppice) are maintained (as high quality future sawlog trees or ‘standards’) ‘above’ a coppice‐origin stand that grows on short rotations (Smith et al. 1997, Jacobs 1955). The SDSS in Appendix D assists with decisions regarding the choice of system. This system is also known as the ‘compound coppice’ system. The standards will be in age classes that are multiples of the length of the coppice rotation (Figure 24).

Figure 24. A Coppice with Standard example, showing retained standards (at least two age classes in light green), standards ready for harvesting at the end of their rotation age (orange), stems to be removed using thinning from below (red), and a marked habitat tree (dark green). The habitat tree also falls outside sawlog prescription (> 60 cm DBHOB). Notice that many 3+ coppice stumps are thinned to one standard.

In Box‐Ironbark forests, the timber from the periodic felling of 90% of the coppice will normally yield small size timber, primarily for firewood, small posts or small poles. The rotation could vary between 15 and 25 years, varying with market opportunities and site quality. At each coppice harvest, some of the standards initially retained are removed ‐ as in the single tree selection system ‐ and some of the best coppice stems are kept as future standards. This process is continued through as many coppice rotations as desired; the number of age classes of the standards increases by one for each coppice harvest until the last of the first standards chosen are harvested. The coppice thinning and any standard thinning/removal should ideally be an integrated operation, but could be separate operations.

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The distribution of diameter classes of the standards should approximate to the inverse J‐curve that is characteristic of a balanced, sustainable uneven‐aged stand (Smith et al. 1997). Many areas of Box‐Ironbark native forest and Sugar Gum plantations in State forest currently resemble CWS, although past silvicultural management has not been deliberate in implementing this system. These stands would now be well suited for management using the CWS system. Advantages of the CWS system include:

 it provides conditions for high quality stems to be grown relatively rapidly  there is little risk of damage to the standards during harvesting ‐ due to wide spacing  the stands are aesthetically pleasing  a range of sawlog sizes as well as firewood, is produced in each cut. Areas suitable for CWS are those of high to medium site quality (suitable for growing Class 1 sawlogs) and with a good stocking of coppice regrowth with or without sawlog‐ size trees, which have not been cut for about 20 years. The stand may include one species or two to three species; for example, E. tricarpa or E. leucoxylon may be favoured as standards and E. microcarpa and E. polyanthemos be better suited to the coppice rotation. Thus a mix of product and silvical properties for each species can be used to manage outcomes. 5.3.2 Marking and harvesting There are three sizes/ages of trees to be removed at each harvest (every 15‐25 years): 1. standards that have failed to grow to the expected potential. These may yield Grade 2 sawlogs or post‐size material. 2. firewood from the coppice crop. 3. the final sawlog trees (i.e. the oldest standards ‐ Grade 1, <60 cm DBHOB). The number of sawlog trees that may be harvested or retained per hectare is not fixed, but varies according to the site quality (or growth potential), the time since the previous felling, and the numbers of habitat trees required to be retained20. The coppice harvest should be carried out with care taken to retain and protect the best stems to grow on as standards. Some of these retained stems, however, will turn out to

20 Current habitat prescriptions require that at least a basal area minimum of 8 m2/ha be retained.

82 Box‐Ironbark Silviculture Reference Manual be defective in some way and will need to be removed in a later cut. NFSG 10 indicates that defective stems should only represent less than 7% of total retained basal area. Table 13 gives a theoretical example of how the numbers could change over the time with a 20‐year cutting cycle, starting with 50 standards per hectare at age 20 years.

Table 13. Stocking (no./ha) of standards over time ‐ an example

Age Harvested New standards Remaining (yrs) standards retained from standards coppice harvest 20 0 0 50 40 10 5 45 60 15 5 35 80 15 10 30 100 10 5 25 120 20 25 30 140 5 10 35 160 10 5 30

5.3.3 Site preparation Generally, site preparation is not required, given that the majority of cut stumps will coppice. However, note the requirement of the SDSS to survey for unstocked gaps and regenerate them from seed where possible. 5.3.4 Regeneration and its protection Regarding protection requirements, as described in section 5.1.4, fuel reduction burning is the main cause of damage to regeneration. This must be minimised by careful planning. Young coppice may be subject to browsing by Swamp Wallabies, but usually at least one stem on each stump should survive and grow above their reach. 5.3.5 Performance measurement After each harvest, use the stocking assessment method as described in section 5.1.5 (Single Tree Selection). 5.3.6 Flora and fauna conservation The measures described under Single Tree Selection (section 5.1.6) also apply to Coppice With Standards coupes.

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5.4 Thinning (commercial) 5.4.1 Description ‘Thinning from below’ (THB) is a silvicultural treatment applied to overstocked regrowth stands (Figure 25), primarily to release potential sawlog trees from competition. Secondary objectives can include immediate wood production, improved wildlife habitat and biodiversity, and an improvement in tree health (Fagg & Bates 2009). Products resulting from commercial THB are Grade 2 sawlogs and firewood. In THB operations carried out by DEPI for domestic firewood, however, trees which contain Grade 2 sawlog material should be left standing, as these also have the potential to grow into the Grade 1 class. For more detail on ‘thinning’, refer to Chapter 4 of this manual and NFSG 15 Thinning of Box‐Ironbark Forests. The SDSS (Appendix D) provides a simple Figure 25. Thinning trial in E. tricarpa at guide when deciding to undertake Dargile established in 1997, as seen in 2001. thinning. Note that cut stumps have coppiced.

5.4.2 Marking and harvesting A pre‐thinning assessment of each stand/coupe proposed for commercial thinning must be carried out prior to the preparation of the Coupe Plan. The assessment procedures are set out in Appendix 1 of NFSG 15 (Fagg & Bates 2009). This involves using a basal area gauge to define which trees are to be sampled (i.e. variable probability sampling), with plot density not less than one plot per three hectares. Appendix 9 of NFSG 10 (2nd edition, Bassett et al. 2014a) contains the techniques for making and using basal area gauges. The assessment results are then compared with the criteria that describe suitable stands (see Table 14 below).

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Table 14. Suitability of Box‐Ironbark stands for commercial thinning (incl. thinning for firewood) (based on Table 3 in NFSG 15)

Criterion Preferred requirement Reasons Slope Generally <15 degrees For ease and safety of operations, and to help minimise tree damage. Basal area Regrowth ‐ generally >12 m2/ha To give an economic volume Overwood* ‐ generally <6 m2/ha, yield. unless a licensee can take multiple products Tree size and Most trees to be removed to be at To improve the economics of 3 volume/ha least 0.05 m the operation. For firewood** not less than 10 m3/ha Height to first green Average not less than 4 m on To ensure some clear log branch dominant and co‐dominant trees length, as thinning may encourage branch retention. Coupe area Minimum of 10 ha To ensure the operation is economical. *Overwood is defined as all trees >60cm DBHOB, all marked habitat trees and current sawlog trees. **Firewood is defined as material not suitable for sawlogs, down to a small end dub of 10 cm.

If the average of plots in a particular area meets all the minimum criteria, all (or part) of the stand is suitable and may be scheduled for thinning. It is essential that the pre‐ thinning basal area, in addition to other information, be recorded on the Coupe Plan. On the scheduled coupes, the tree marker must first identify any existing and potential Grade 1 sawlog trees (and Grade 2 sawlog trees if in a domestic firewood coupe) and ensure that they are retained. Also habitat trees must be retained as per Appendix E. Note that in firewood operations, trees are marked to retain, not to remove (in contrast to sawlog operations in which trees are marked to remove). Trees to remove should be suppressed, damaged, unhealthy or of poor form. A small amount (<20%) of mistletoe or dodder in a crown is acceptable for retention.

Up to a maximum of 60% of the initial live basal area (BA) may be removed provided that the total* retained average BA does not fall below 8 m2/ha. * includes habitat trees as well as regrowth.

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In Box‐Ironbark forests the normal thinning from below (THB) method is termed ‘uniform’ ‐ in which all potential crop/sawlog trees are retained21. Currently, a typical thinning operation for firewood involves hand‐falling using chainsaws, followed by cross‐cutting of the trees into billets, then removal of the billets from the forest on a tray truck. Operators must comply with the relevant sections of the Timber Harvesting Operator’s Procedures (DSE 2008). Damage may be accidently caused to retained trees by trees being felled, and by machinery striking trees and breaking off bark. Any exposure of the underlying wood can allow decay‐causing fungi to enter and therefore downgrade future log quality. In thinning, the number of damaged trees must be no more than an average of 10% of the retained crop trees.

‘Damage’ is defined as: breakage of the bark‐wood bond, of more than 100 cm2 on the main bole ‐ whether the bark is fully removed (= ‘open’ wound) or not (= ‘closed’ wound) OR breakage or removal of >30% of the original crown.

5.4.3 Stump and coppice competition Note that site preparation and regeneration actions are not required for THB, as regeneration is not wanted or required. Nevertheless, coppice will regrow from most stumps and compete for soil moisture with the retained trees. In some situations where it may be important to minimise this competition, up to 25% of cut stumps (or coppice shoots from 25% of cut stumps) may be killed by using a glyphosate‐type herbicide, according to the label (see NFSG #15 ‐ pp. 7‐8 Fagg & Bates 2009).

5.4.4 Performance measurement Thinned coupes in Box‐Ironbark State forests must be assessed by the supervisor according to the procedure described in NFSG 15 ‐ Appendix 2, to ensure that the prescriptions are being, or have been, followed. Timely collection of data allows the supervisor to provide feedback to contractors or crews, especially in relation to thinning intensity, choice of trees and damage incidence. 5.4.5 Flora and fauna conservation The measures described under Single Tree Selection (section 5.1.6) also apply to THB.

21 Unlike ‘Outrow and Bay’ thinning which is practiced in dense eucalypt forests.

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5.5 Thinning (pre‐commercial) ‘Pre‐commercial thinning’ (PCT) (syn. ‘non‐commercial thinning and ‘early spacing’) is the manual or mechanical thinning of a young, dense stand in which the trees cut or injected are not merchantable (Figure 26). Thinning of coppice stems on stumps or dense young seedling regrowth, that is, pre‐ commercial thinning (PCT) is not a common practice in Box‐Ironbark forests. However, it may be a project associated with periodic unemployment relief schemes. Refer to Table 4 in NFSG 15 for criteria that will assist in deciding if a stand is suitable for PCT. As the name implies, stands selected for PCT should be capable of supporting a commercial thinning at a later date. PCT, in addition to accelerating the growth of selected Figure 26. A young, dense stand of E. tricarpa and Box species near Bendigo, with potential for pre‐ stems, will reduce the time to reach commercial thinning economic first thinnings (La Sala 2000, Raison et al. 1995).

While there are a variety of techniques available for PCT operations, experience has shown that the ‘nick and squirt’ method of stem injection using a modified tomahawk and spot‐gun, is more effective and economic than mechanical treatments. However, there may be situations where chainsaws, clearing saws or axes may be more appropriate to use. NFSG 15 describes all potential methods and gives guidance on the retained stem density in PCT.

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5.6 Ecological thinning 5.6.1 Description ‘Ecological Thinning’ (ETB) is appropriate in Box‐Ironbark forests where the main objectives are to improve habitat for fauna and to enhance conditions for understorey flora (Figure 27). The rationale is that by heavily thinning (from below), the retained trees will grow faster and in time, being larger, should produce more hollows and have larger crowns that will benefit certain species of animals which currently have depleted populations (ECC 2001). The ‘B’ in ETB refers to ‘below’, as the removed trees should be almost always smaller than the trees to be retained. Usually, the thinned timber is left on the ground as coarse woody debris (CWD) for habitat for ground‐dwelling species, but in some cases, the timber could potentially be removed for firewood. In some situations, the unwanted trees can be removed by injecting them with herbicide, and therefore they remain standing.

Figure 27. Ecological thinning of a Box‐Ironbark forest at Pilchers Bridge, south east of Bendigo in 2008. Thinning is expected to improve the biodiversity of this site.

This system has been trialled with some success in national parks and other types of conservation reserves in Victorian Box‐Ironbark forests (Pigott et al. 2008), but could also be employed in State forests where timber production is a secondary or minor

88 Box‐Ironbark Silviculture Reference Manual objective. Trust for Nature have developed guidelines where private land owners manage Box‐Ironbark stands for flora and fauna conservation (Forest Solutions 2010). The following sections are based on Chapter 5 of Fagg and Bates (2009), relevant parts of Forest Solutions (2010), and Pigott et al. (2008). 5.6.2 Planning Planning work for Ecological Thinning (ETB) is driven by the primary objectives, which normally include one or more of the following: 1. To increase retained tree size over time, by removing smaller, competing trees 2. To increase levels of coarse woody debris (to a minimum level) to enhance habitat and reduce excessive rainfall run‐off and erosion from sloping areas 3. To improve understorey coverage and diversity 4. To ensure, on a block‐scale, a balance of tree sizes and densities. Note that achievement of the first objective will generally result in the other objectives also being achieved. The choice of compartments or coupes for ETB should consider the following: 1. The animal and/or plant species being considered for habitat enhancement 2. The current condition/features of the forest (as described in Table 15) and their potential to respond to the treatment 3. The resources (human and financial) available to undertake the work, which is often slow and costly when stands are dense. Undertake a pre‐thinning assessment to determine the suitability of a stand for ecological thinning and use Table 15 to prioritise sites where ETB should be carried out.

In ETB, the operating prescriptions would usually include: 1. Retain (a specified number of) larger trees, regardless of their form; living or dead 2. Retain all hollow‐bearing trees and any stump hollows, regardless of size 3. Maintain original tree species representation in those retained 4. Retain trees bearing small numbers of mistletoes 5. Avoid damage to understorey plants, where practicable 6. Paint freshly cut stumps with herbicide and/or inject trees with herbicide, as specified.

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Table 15. Suitability of Box‐Ironbark stands for ecological thinning (based on Fagg & Bates 2009). ‘Preferred’ represents the stand attributes of highest priority for thinning. ‘Acceptable’, while not ideal, will suffice.

Criterion Preferred Acceptable Reason requirement requirement

Age 5‐40 years No variation Stands of these ages are most likely to be overstocked. Culling of older trees is not desirable. Slope <10o 10‐15o Lower slopes are safer for work crews. Site quality or High Moderate‐Low Better quality sites will respond and growth produce larger trees sooner, but retained potential trees on low quality sites will also respond. Area to be >10 ha 4‐10 ha If <10 ha, value to fauna decreases and treated unit costs may increase. Small trees >3,000 >1,000 These are the regrowth size classes that 10‐20 cm stems/ha stems/ha often ‘lock‐up’ and require thinning DBHOB Medium trees 30‐45 15‐30 Retain for growing into larger habitat 30‐60 cm stems/ha stems/ha trees. DBHOB Large trees nil <10 Stands where large trees already exist are 70+ cm stems/ha lower priority to thin. DBHOB Stocking >RBA m2/ha Up to 20% Stands >RBA are overstocked and require below RBA release more urgently. These densities are too high:  5‐10 years old – 3,000 stems/ha  30‐40 years old ‐ >300 stems/ha RBA stands for ‘Reference Basal Area’

5.6.3 Methods of ecological thinning treatment For young regrowth in stands of density 3‐6,000 stems/ha, use techniques described as for pre‐commercial thinning (section 5.5). Where trees are older than about 15 years, chainsaws are required for felling. Stem injection with herbicide, however, is a cheaper and safer technique than felling trees. This will result in killing the stump and root system, which may be a desirable outcome in ecological thinning (ETB), to minimise competition to the retained trees. Stem injection of standing trees reduces the fire risk of treated areas, as the fuel is not concentrated on the ground as in felling. In addition, when a bushfire does occur, access into the stand is much easier than if there are many logs lying on the forest floor.

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Table 16. Recommended retained tree densities for ecological thinning (ETB) in Box‐Ironbark regrowth forest (from Table 7 in NFSG 15).

Age of regrowth Average density of retained (larger) trees Average spacing (years) between trees 8‐13 700 stems/ha 4 m 14‐30 400 stems/ha 5 m >30 Minimum basal area of 6 m2/ha n/a (not less than 30% of initial basal area) OR 30 of the largest trees/ha 18 m Note that spacing given is only a guide, as two dominant or co‐dominant trees close together should always be retained in ETB.

Note: if one of several stems in a coppice clump is to be retained, stem injection of the other stems may result in injury to the retained stem. This should be avoided until research proves that such injection can be done safely. Registered herbicides, such as glyphosate (at the recommended dilution), either painted on fresh stumps or sprayed on coppice leaves, can be used to kill stumps. Experience to date indicates that ‘flash back’ kill of nearby untreated stumps is minimal (P. Pigott, pers. comm., Parks Victoria). Mechanised methods of thinning using felling ‘heads’ attached to boom arms on machines potentially can thin regrowth much faster than manual methods, but one disadvantage of this technique is that the operator (in his cabin) may not be able to properly assess which trees to leave or cut. 5.6.4 Performance measurement The success of ecological thinning is assessed according to whether: (a) all trees which should have been treated were treated, including stump treatment, if used, (b) the retained trees are growing faster in diameter and crown density, (c) increased numbers of the target fauna species, especially hollow‐using mammals and birds, and animals which require course woody debris (CWD), are occurring, (d) the understorey is improved in terms of species and coverage. The stand parametres could be assessed by measuring stem numbers and diametres, understorey species and coverage, and CWD levels on plots both before and soon after the thinning, then at intervals, approximately every five years. A suitable technique for measuring the level of CWD is included in Appendix 2 of Forest Solutions (2010).

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Biodiversity responses could be assessed using a range of standard techniques for different groups of species, for example, timed area‐searches for diurnal birds, nocturnal surveys for arboreal mammals with call playback for owls, live‐trapping or camera‐trapping for ground‐dwelling mammals, ultrasonic recorders for bats, active timed searches for reptiles, and call surveys for frogs. The surveys would need to be conducted in multiple stands where thinning had been conducted recently, compared with control stands where no such action had been taken. Retrospective studies in stands thinned in the past could be very helpful for elucidating longer‐term effects, as some expected benefits of thinning may take many years to come to fruition (e.g. of hollow formation). Diurnal birds would be the most efficient group to study, as they can be surveyed rapidly and include species that are hollow‐ dependent, as well as species that may respond to structural changes associated with thinning or other processes that may be affected in various ways, for example, nectar production. 5.6.5 Flora and fauna conservation The whole objective of ecological thinning is to improve habitat for fauna (including increased coarse woody debris) and enhance conditions for understorey growth.

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6. Reforestation and remedial regeneration 6.1 Reforestation/rehabilitation The need for reforestation, as distinct from remedial regeneration treatment, is mainly restricted to situations where there has been a man‐made vegetation change or removal in the past (Yates & Hobbs 1997). This includes where forest has been cleared for agriculture, burnt too often by bushfires or even converted to pine plantations, and there is a requirement to return the land back to native forest. While much of the Box‐Ironbark forest type has been cleared in the past for agriculture, there have been only limited projects aimed at revegetation with the endemic species, mainly because the large majority of the land is privately owned. The Delatite Arm Regeneration project, which began in 2001, is revegetating approximately 2,000 hectares of former State‐owned pine plantation following harvesting on the Delatite Arm of Eildon Weir in north east Victoria. Native box species being regenerated by direct sowing and planting of seedlings include E. polyanthemos, E. melliodora, E. macrorhyncha and E. goniocalyx (Long‐leaved Box) (DSE 2004, Figure 28a).

Figure 28. Two recent reforestation projects: (a) An E. polyanthemos seedling and a mix of other Box‐Ironbark species planted during the Delatite Arm Regeneration project, Mansfield district, and (b) 18 year old E. tricarpa and E. microcarpa saplings established on a rehabilitated mine site, Craige State forest.

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State forest areas that have been mined for gold, clay or stone in recent years must be rehabilitated (ECC 2001). This is a form of reforestation (Figure 28b). Given only about 15% of the areal extent of pre‐settlement Box‐Ironbark remains, there may be a requirement to enhance or expand this extent at the landscape scale. For example, remnant isolated patches, often on private agricultural land, could be expanded and/or linked to larger existing State managed forests. This is expected to also have other ecosystem benefits such as water table management (Yates & Hobbs 1997). Limited knowledge and information is available about the restoration (and reforestation) of temperate eucalypt woodlands (Yates & Hobbs 1997). Ecological thinning has a role in restoring or enhancing the biodiversity of existing Box‐Ironbark forests (see section 5.6). Simply excluding (fencing) grazing stock from areas adjacent to Box‐Ironbark forest may enable a woodland expansion, albeit slow. Linkage corridors would require direct reforestation. The following guidelines for rehabilitation/reforestation are based on general knowledge and experience: 1. Collect seed from as many species as practical from the site intended. 2. During operations such as mining, where soils are severely disturbed, stockpile the topsoil layer in an area not subject to erosion. Also stockpile some woody debris for relocation back onto the rehabilitated site. 3. Test the seed for viability and raise seedlings of relevant species if the site is to be planted. 4. As soon as practical after extraction operations, re‐spread the topsoil layer adding an appropriate NPK fertiliser. (Note: in some situations, as where direct sowing is planned, the ripping can be done before re‐spreading the topsoil). 5. If the topsoil depth is less than 30 cm, contour rip the site using a winged ripper to a depth of 40‐50 cm and spacing of not more than two metres. (Note: ensure that ripping coincides with relatively dry conditions in order to facilitate effective shattering of compacted soil and subsoil layers ‐ refer to Poynter 2004). 6. If planting has been planned, in winter or early spring, plant seedlings adjacent to (not in) the rip‐lines, mixing up the species where there is more than one. 7. If direct sowing has been planned, in autumn, broadcast sow the collected seed at the rate calculated on the basis of the viability (i.e. viable seeds/kg). Table 17 lists the recommended broad‐scale sowing rates for a selection of species based on ecological or timber production stocking objectives (Bassett et al. 2014).

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8. Undertake browsing animal control, if judged necessary, to protect young seedlings from native browsers and agricultural grazing stock. 9. Carry out a stocking survey within 12 months of sowing or planting. If stocking is inadequate, undertake infill planting. Survey at two to three years to confirm that stocking meets the minimum required standard. 10. Sites in use should progressively rehabilitated, that is each year, rehabilitate the area disturbed within that year. This will maximise stocking success.

Table 17. Recommended artificial sowing rates for a selection of Box‐Ironbark species, based on germination % (for E. tricarpa), seed size, and known average viabilities.

Sow rate (vs/ha) Species environmental Timber production E. tricarpa 80,000 150,000 E polyanthemos 100,000 200,000 E. melliodora 100,000 200,000 E. goniocalyx 80,000 150,000

Figure 29 shows a mine site recently rehabilitated with Box‐Ironbark eucalypts and Acacia species in the Daisy Hill State forest. Note the retention of course woody debris.

6.2 Remedial (or backlog) regeneration The Box‐Ironbark forest type regenerates consistently well after harvesting. Data shows that 95% of the 2,130 ha that were harvested for sawlogs (before the 2001 ECC recommendations were implemented) was successfully stocked based on surveys after the timber harvesting (Fagg et al 2008). This is largely due to the use of the selection silvicultural system and the fact that cut stumps usually re‐sprout, thus providing regeneration. 6.2.1 Procedures In the uncommon situation where coupe stocking is very low or there are understocked gaps of more than two hectares, as identified in the stocking survey carried out after harvesting, the course of action to improve stocking should follow that described under Group Selection (see section 5.2). This will involve seedbed preparation, sowing collected seed and follow‐up protection from browsing animals.

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Figure 29. A recently rehabilitated mine site, in Daisy Hill State forest, showing Eucalyptus and Acacia regrowth as well as retained course woody debris.

Site preparation Very small areas with an unreceptive seedbed and negligible competition could be prepared by hand using a ‘rake‐hoe’ or similar tool. Otherwise, site preparation is carried out mechanically by ripping the site to improve soil conditions for root development and moisture retention. Alternatively, if there is enough harvesting debris (slash) left on site, it is desirable to burn these heaps to create seed‐receptive ashbeds and increase the proportion of the site available for seedling establishment. NFSG 6 Site Preparation (Lutze & Geary 1998) provides a more detailed outline of site preparation, including guiding principles, planning, operational techniques and seedbed assessments. Sowing There will rarely be an adequate seed supply on retained trees, so supplementary sowing will need to be scheduled. The seed is either sown by hand using coated seed or by using a hand‐operated ‘spinner’, the correct kg/ha sowing rate having been established by calibration. Refer to NFSG 8 Eucalypt Sowing and Seedfall (Fagg 2001) for more information on procedures and prescriptions. Table 17 provides some sow rate information, recommended by Forest Solutions in 2014 for DEPI’s DAR project.

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Planting Planting of seedlings raised 9‐12 months previously may be more successful than sowing seed on site, but is much more expensive. Planted seedlings are quite attractive to browsing animals, so that protection options as outlined under section 5.2.4 should be implemented. Refer to NFSG 9 Raising and Planting Eucalypts (Bassett et al. 2014b) for more information on procedures and prescriptions. E. tricarpa seedlings planted at a density of 2,500/ha on a flat, poorly drained (dieback) site in East Gippsland, grew slowly at 13 cm/yr, but faster (29 cm/yr) when inter‐ planted with Acacia longifolia (Sallow Wattle). E. tricarpa is tolerant of P. cinnamomi attack and mortality was very low (5%) (Smith et al. 1989). Lutze (1998) reported on an E. tricarpa planting trial in East Gippsland, in an attempt to improve the native eucalypt diversity. After nine years, survival of the seedlings was adequate, but this was dependent on overwood removal prior to planting and reduced understorey competition. Survival also improved following browsing protection. 6.2.2 Performance measurement Monitoring of all aspects of a re‐treatment operation is important, since monitoring immediately indicates likely success throughout the operation. Any early issues may be more cost‐effectively addressed once they are detected during monitoring. Monitoring can include germination and survival monitoring plots, Preliminary and Established Seedling Surveys in addition to Browsing Risk Assessments and Browsing Indicator Plots as required. These should all be conducted in accordance with the methods described in NFSG 7 and NFSG 10.

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References

Listings in Bold are key references

Adair, R.J. & Bruzzese, E. (2006). Blackberry‐ treading a prickly path to effective biological control in Australia. Proc. 15th Australian Weeds Conference – managing weeds in a changing climate, 557‐560 pp. Adkins, M.F., Westbrooke, M.E., Florentine, S.R. & McDonald, S.P. (2005). Fire and hollow formation in Box‐Ironbark eucalypts of the Warby Range State Park. The Victorian Naturalist 122: 47‐56. Andersen, A.N. (1987). Effect of seed predation by ants on seedling densities at a woodland site in SE Australia. Oikos 48: 171‐174. Ashton, D.H. (1975). Studies of flowering behaviour in E. regnans F. Muell. Australian Journal of Botany 23: 399‐411. Ashton, D.H. (2000). Ecology of Eucalypt Regeneration. Chap. 4 In Diseases and Pathogens of Eucalypts, Eds. Keane, Kile, Podger & Brown, CSIRO Publishing, Collingwood, Victoria, 565 pp. Bari, M.A. & Ruprecht, J.K. (2003). Water yield response to land‐use change in south‐ west Western Australia. Salinity and Land‐use Impacts Series Report No. SLU31, Department of Environment, Western Australia. Barker, J., Grigg, G.C., & Tyler, M.J. (1995). A field guide to Australian frogs. Surrey Beatty & Sons, Chipping Norton, New South Wales. Bassett, O.D. (2002). Flowering and seed crop development in Eucalyptus sieberi L. Johnson and E. globoidea Blakely in a lowland sclerophyll forest in East Gippsland, Victoria. Australian Forestry 65: 237‐255. Bassett, O.D. (2014). Seed Crop Monitoring and Assessment. Native Forest Silviculture Guideline No. 1. 2nd edn, Department of Environment and Primary Industries, Victoria, 76 pp. Bassett, O.D. & White, G. (2001). Review of the impact of retained overwood trees on stand productivity. Australian Forestry 64: 57‐63. Bassett, O.D., White, M.D. & Dacey, M. (2006). Development and testing of seed‐crop assessment models for three lowland forest eucalypts in East Gippsland, Victoria. Australian Forestry 69: 257‐269.

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Bassett, O.D. & Paterson C. (2011). Report of Decommission Audits Undertaken on Victoria’s Seed Facilities during 2011. Prepared by Forest Solutions for the Department of Sustainability and Environment, Victoria, 23 pp. Bassett, O.D., Fagg, P.C., Slijkerman, C. & Lutze, M. (2014a). Eucalypt stocking surveys and regeneration monitoring. Native Forest Silviculture Guideline No. 10, 2nd edn. Department of Environment and Primary Industries, Victoria, 78 pp. Bassett, O.D., Fagg, P.C., Slijkerman, C. & Lutze, M. (2014b). Raising and Planting Eucalypts. Native Forest Silviculture Guideline No. 9, 2nd edn. Department of Environment and Primary Industries, Victoria, 49 pp. Batini, F., Bradshaw, J. & Underwood, R. (2007). Managing forested catchments for water, timber and biodiversity. In Proceedings of ANZIF Conference, 2007, Institute of Foresters of Australia, Canberra, ACT. Bennett, A.F., Holland, G.F., Flanagan, A., Kelly, S. & Clarke, M.F. (2012). Fire and its interaction with ecological processes in box‐ironbark forests. Proceedings of the Royal Society of Victoria 124(1): 72‐78. Boland, D.J. (1978). Geographic variation in Eucalyptus leucoxylon F.Muell. Australian Forest Research 8: 25‐46. Boland, D.J., Brooker, M.I.H. & Turnbull, J.W. (1980). Eucalyptus Seed. CSIRO, Canberra, ACT, 191 pp. Boland, D.J. & Martensz, P.N. (1981). Seed losses in fruit on trees of Eucalyptus delegatensis. Australian Forestry 44: 64‐57. Boland, D.J., Brooker, M.I.H., Chippendale, G.M., Hall, N. et al. (2006). Forest Trees of Australia. 5th edn, CSIRO Publishing, Melbourne, Victoria, 736 pp. Bougher, N.L., Grove, T.S. & Malajczuk, N. (1990). Growth and phosphorus acquisition of karri (Eucalyptus diversicolor) seedlings inoculated with ectomycorrhizal fungi in relation to phosphorus supply. New Phytologist 114: 77‐85. Bramwells, H.W. & Whiffin, T. (1984). Patterns of variation on Eucalyptus sideroxylon A. Cunn. Ex. Woolls. 1. Variation in Adult Morphology. Australian Journal of Botany 32: 263‐281. Briggs, L. (1993). Apiculture in Box and Ironbark Forests. Proc. 1992 VNPA Conference. The Victorian Naturalist 110: 38‐44. Brooker, M.I.H. & Slee, A.V. (1996). Eucalyptus. In Flora of Victoria. Dicotyledons: Winteraceae to Myrtaceae. (Eds. N.G. Walsh & T.J. Entwisle.) Inkata Press, Melbourne, Victoria, pp 1093.

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Brown, B.N. (2000). Diseases and Fungi of the Reproductive Structures of Eucalypts. Chap.7 In Diseases and Pathogens of Eucalypts (Eds. Keane, Kile, Podger and Brown) CSIRO Publishing, Collingwood, Victoria. Brown, G.W. (2001). The influence of habitat disturbance on reptiles in a Box‐Ironbark eucalypt forest of south‐eastern Australia. Biodiversity & Conservation 10: 161‐176. Campbell, R.G., Chesterfield, E.A., Craig, F.G., Fagg, P.C., Farrell, P.W., Featherston, G.R., Flinn, D.W., Hopmans, P., Kellas, J.D., Leitch, C.J., Loyn, R.H., Macfarlane, M.A., Pederick, L.A., Squire, R.O., Stewart, H.T. L. & Suckling, G.C. (1984). Silvicultural and environmental aspects of harvesting some major commercial eucalypt forests in Victoria. Forests Commission Victoria, 176 pp. Carr, S.G.M. & Carr. D.J. (1968). Operculum development and the taxonomy of eucalypts. Nature 219, 3 August: 513‐515. Chambers, D. (2006). Wooden Wonders: Victoria’s Timber Bridges, Hyland House Publishing, Flemington, Victoria, 207 pp. Christidis, L. & Boles, W.E. (2008). Systematics and Taxonomy of Australian Birds. CSIRO Publishing, Collingwood, Victoria, 277 pp. Cogger, H.G. (2014). Reptiles and Amphibians of Australia. CSIRO Publishing, Collingwood, Victoria, 1,064 pp. CFL (1989). Termites in Victoria. Research & Development No. 13, Lands & Forests Division, Department of Conservation Forests and Lands, Victoria. Chilvers, G.A. (2000). Mycorrhizas of Eucalypts. Chapter 6 In Diseases and Pathogens of Eucalypts (Eds. Keane, Kile, Podger and Brown) CSIRO Publishing, Collingwood, Victoria. Collett, N.G. & Fagg, P.C. (2010). Insect defoliation of mixed‐species eucalypts in East Gippsland Australian Forestry 73: 81‐90. Costermans, L. (2006). Trees of Victoria and Adjoining Areas. 6th edn. Costermans Publishing, Frankston, Victoria, 164 pp. Cremer, K.W. (1965). How eucalypt fruits release their seeds. Australian Journal of Botany 13: 11‐16. Cremer, K.W. (1977). Distance of seed dispersal in eucalypts estimated from seed weights. Australian Forest Research 7: 225‐228. DEPI (2014a). State of the Forests Report 2013. Department of Environment and Primary Industries, Melbourne, Victoria, 269 pp.

100 Box‐Ironbark Silviculture Reference Manual

DEPI (2014b). Code of Practice for Timber Production, Department of Environment and Primary Industries, Melbourne, Victoria. DEPI (2014c). Management Standards and Procedures for timber harvesting operations in Victoria’s State forests. Department of Environment and Primary Industries, Melbourne, Victoria. Dexter, B.D. (1960). Seed supply and field germination in the natural regeneration of Eucalyptus sideroxylon A. Cunn. MS, School of Forestry, University of Melbourne, 47 pp. (unpublished) Dignan, P. & Fagg, P. (1997). Eucalypt Stocking Surveys. Native Forest Silviculture Guideline No.10, Forests Service, Department of Natural Resources and Environment, Victoria, 84 pp. (Has been revised – see Bassett et al. 2014b) Dooley, G. (2004). Beekeeping and forestry practices in some Victorian State forests. Forest Research Report No. 391. Parks and Forests Division, Department of Sustainability and Environment, Melbourne, Victoria, 25 pp. DPI (2011). Timber Industry Action Plan Department of Primary Industries, Melbourne, Victoria, 18 pp. Drake, D.W. (1974). Fungal and insect attack on seeds of unopened Eucalyptus capsules. Search 5: 444. DSE (2004). Operations Manual. Delatite Arm Regeneration Project, Department of Sustainability and Environment, Victoria. DSE (2007). Code of Practice for Timber Production, Department of Sustainability and Environment, Melbourne, Victoria. (Revised 2014, see DEPI (2014b)) DSE (2008). Forest Management Plan, BendigoForest Management Area, Department of Sustainability and Environment, Melbourne, Victoria, 57 pp. DSE (2012). Code of Practice for Bushfire Management on Public Land, Department of Sustainability and Environment, Melbourne, Victoria, 44 pp. DSE (2013). Advisory list of threatened vertebrate fauna in Victoria. Department of Sustainability and Environment, Melbourne, Victoria, 21 pp. ECC (1997). Box‐Ironbark Forests and Woodlands Investigation ‐ Resources and Issues Report. Environment Conservation Council, East Melbourne, Victoria, 265 pp. ECC (2001). Box‐Ironbark Forest and Woodlands Investigation ‐ Final Report. Environment Conservation Council, East Melbourne, Victoria, 296 pp + Appendices.

Box‐Ironbark Silviculture Reference Manual 101

Edgar, W.J. (1960). Working Plan for the Chiltern Forest. Thesis, Dip. For. Vic, University of Melbourne, Victoria. Eldridge, K.G., Davidson, J. Harwood, C. & van Wyk, G. (1993). Eucalypt Domestication and Breeding, 1st edn. Oxford University Press: New York. Elliott, H.J., Ohmart, C.P. & Wylie, F.R. (1998). Insect Pests of Australian Forests – Ecology and Management, Inkata Press, Melbourne, Victoria, 214 pp. Emison, W.B., Beardsell, C.M., Norman, F.I., Loyn, R.H. & Bennett, S.C. (1987). Atlas of Victorian Birds. Department of Conservation, Forests & Lands with Royal Australasian Ornithologists Union, Melbourne, Victoria, 271 pp. Fagg, P.C. (1997). Mistletoe in forest management in Victoria. The Victorian Naturalist 114(3): 112‐115. Fagg, P.C. (2001). Eucalypt Sowing and Seedfall. Native Forest Silviculture Guideline No. 8, Forestry Victoria, Department of Natural Resources and Environment, Melbourne, Victoria, 41 pp. Fagg, P.C. (2003). Research and Development Action Groups – a model for linking forest research, policy and field operations. Proceedings of the Australian and New Zealand Institute of Forestry Conference, Queenstown, New Zealand, April‐May 2003, 443‐ 449 pp. Fagg, P.C., Meyers, N.D. & Bassett, O.D. (2008). Stocking following harvesting and regeneration in Victoria’s State forests (1996/97 ‐ 2000/01). Natural Resources Report Series 08‐1, Department of Sustainability and Environment, Melbourne, Victoria, 52 pp. Fagg, P. & Bates, P. (2009). Thinning of Box‐Ironbark forests. Native Forest Silviculture Guideline No. 15, Department of Sustainability and Environment, Melbourne, Victoria, 36 pp. Featherston, G.R. (1985). Harvesting history of a coastal forest area in East Gippsland in relation to eucalypt species composition. Forest Research Report No. 290, Department of Conservation, Forests and Land, Melbourne, Victoria, 17 pp. Ferguson, K.V.M. (1934). A preliminary experiment to determine a suitable method of securing natural regeneration from seed on cut‐out areas of red ironbark (Euc. sideroxylon). Victorian Forester 1(1): 26‐28. Flint, A. & Fagg, P. (2007). Mountain Ash in Victoria’s State forests. Silviculture Reference Manual No. 1. Department of Sustainability and Environment, Melbourne, Victoria, 97 pp.

102 Box‐Ironbark Silviculture Reference Manual

Florence, R.G. (1996). Ecology and Silviculture of Eucalypt Forests. CSIRO, Melbourne, Victoria, 413 pp. Ford, R.M., Williams, K,J.H., Bishop, I.D. & Hickey, J.E. (2009). Public judgments of the social acceptability of silvicultural alternatives in Tasmanian wet eucalypt forests. Australian Forestry 72: 157‐171. Forest Solutions (2010). Ecological Thinning Guidelines for Regrowth Forests and Woodlands on Private Land ‐ technical thinning considerations for landholders and land managers. Forest Solutions (Consultant Report for Trust for Nature), Benalla, Victoria, 43 pp. Forest Solutions (2013). Review of Commercial Forestry Management in Western Victoria ‐ Timber resources, Harvest Levels, Silviculture, and Systems and Processes. Prepared by Forest Solutions for the Department of Environment and Primary Industries, Victoria, 83 pp. Gibbens, J. (2000). Changes in ant and termite activity and community structure as indicators of ground layer disturbance in Box‐Ironbark forest. The Victorian Naturalist 117(4): 124‐130. Gill, E. D. (1936). Notes on dodder eradication. Victorian Forester 1(3): 15‐16. Gloury, C. (1998). The distribution and edaphic/bioclimatic analysis of summer flowering Eucalyptus tricarpa. Forest Science Honours project. University of Melbourne, Victoria. Goodman, R. D. (1973). Honey Flora of Victoria. Department of Agriculture, Victoria, 174 pp. Goodman, R.D. (2001). Beekeepers use of Honey and Pollen flora Resources in Victoria. A report for the Rural Industries Research and Development Corporation (RIRDC), Department of Natural Resources and Environment, Victoria, and RIRDC. Grey, M.J., Clarke, M.F. & Loyn, R.H. (1997). Initial changes in the avian communities of remnant eucalypt woodlands following a reduction in the abundance of Noisy Miners Manorina melanocephala. Wildlife Research 24: 631‐648. Groch, A. (2006). Bendigo State Forests. Forests Note FS0069, Department of Sustainability and Environment, Melbourne, Victoria, 5 pp. Grose, R.J. & Zimmer, W.J. (1957). Preliminary laboratory studies on light requirements for the germination of some eucalypt seeds. Australian Forestry 21:76‐80.

Box‐Ironbark Silviculture Reference Manual 103

Grose, R.J. & Zimmer, W.J. (1958a). A description of the seeds of 70 Victorian eucalypts (illustrated). Bulletin No. 8. Forests Commission of Victoria, Melbourne, Victoria, 29 pp. Grose, R.J. & Zimmer, W.J. (1958b). The collection and testing of seed from some Victorian eucalypts with results of viability tests. Bulletin No. 10. Forests Commission of Victoria, Melbourne, Victoria, 14 pp. Grove, T.S., Thomson, B.D., & Malajczuk, N. (1996). Nutritional physiology of eucalypts: uptake, distribution and utilization. In Nutrition of Eucalypts, (Eds Attiwill, & Adams) CSIRO, Melbourne, Victoria, 77‐108 pp. Harwood, C., Bulman, P., Bush, D., Mazanec, R. & Stackpole, D. (2001). Compendium of Hardwood Breeding Strategies. Australian Low Rainfall Tree Improvement Group. A report for the RIRDC/LWA/FWPRDC Joint venture agro‐forestry program. Rural Industries Research and Development Corporation. Hateley, R.F. (2010). The Victorian Bush: its ‘original and natural’ condition. Polybractea Press, South Melbourne, Victoria, 209 pp. Holland, G.J., Alexander, J.S.A., Johnson, P., Arnold, A.H., Halley, M. & Bennett, A.F. (2012). Conservation cornerstones: capitalising on the endeavours of long‐term monitoring projects. Biological Conservation 145: 95‐101. Hooper, V. (1992). Mining My Past. A life in gold mining ISBN 0 646 09436 X. Mike McCarthy Printing. Maryborough, Victoria. Hudson, I.L. & Keatley, M.R. (2013). Scoping the budding and climate impacts on eucalypt flowering non‐linear time series decomposition modelling. 20th International Congress on Modelling and Simulation. Adelaide, Australia. 1‐6 December 2013. Jacobs, M.R. (1955). The Growth Habits of the Eucalypts. Government Printer, Canberra, ACT, 262 pp. Keatley, M.R (1999). The flowering phenology of Box‐Ironbark Eucalypts in the Maryborough Region, Victoria. Thesis submitted for the degree of Doctor of Philosophy. University of Melbourne, Victoria. Keatley, M. R., Fletcher, T. D., Hudson, I. L. and Ades, P. K. (2002). Phenological studies in Australia: Potential application in historical and future climate analysis. International Journal of Climatology 22: 1769‐1780. Keatley, M.R., & Hudson, I.L. (2007). A comparison of long‐term flowering patterns of Box‐Ironbark species in Havelock and Rushworth forests. Environmental Model Assessment 12: 279‐292.

104 Box‐Ironbark Silviculture Reference Manual

Keatley, M.R., Hudson, I.L. & Fletcher, T.D. (2004). Long term flowering synchrony of Box‐Ironbark eucalypts. Australian Journal of Botany 52: 47‐54. Keatley, M.R. & Murray, M.D. (2010). Flowering and seed crop development of Eucalyptus tricarpa in East Gippsland. Forest Research Report No. 399, Parks and Forests Division, Department of Sustainability and Environment, Melbourne, Victoria, 25 pp. (unpubl.) Keatley, M.R. & Hudson, I.L. (2012). The influence of budding on the flowering of four eucalypt species. Phenology 2012: Climate change impacts and adaptations, 119 pp. Kellas, J.D. (1991). Management of dry sclerophyll forests in Victoria. 1. Box‐Ironbark forests. Chap.9 In Forest Management in Australia (Eds. McKinnell, Hopkins & Fox), Surrey Beatty & Sons, Sydney, New South Wales. Kellas, J.D. (1994). Silvical characteristics of Messmate Stringybark and Narrow‐leaved Peppermint under partial cutting conditions. II: Factors influencing germination, survival and early growth Research Report No. 359. Forests Service, Department of Conservation and Natural Resources, Victoria, 33 pp. Kellas, J.D., Owen, J.V. & Squire, R.O. (1982). Responses of Eucalyptus sideroxylon to release from competition in an irregular stands. Forestry Technical Papers 29:33‐36, Forests Commission Victoria. Kellas, J.D., Oswin, D., & Ashton, A. (1998). Growth of red ironbark between 1972 and 1995 on research plots in the Heathcote Forest. Forest Research Report No. 363, Forestry Victoria, Department of Natural Resources and Environment, Melbourne, Victoria. Kelly, L.T. & Bennett, A.F. (2008). Habitat requirements of the Yellow‐footed Antechinus (Antechinus flavipes) in Box‐Ironbark forest, Victoria, Australia. Wildlife Research 35: 128‐133. Kile, G.A. (1981). Armillaria luteobubalina a primary cause of decline and death of trees in mixed species eucalypt forest in central Victoria. Australian Forest Research 11: 63‐77. Kile, G.A. (2000). Woody root rots of eucalypts. Chap. 12 In Diseases and Pathogens of Eucalypts (Eds. Keane, Kile, Podger and Brown) CSIRO Publishing, Collingwood, Victoria. Kile, G.A. & Johnson, G.C. (2000). Stem and Butt Rot of Eucalypts. Chap. 13 In Diseases and Pathogens of Eucalypts (Eds. Keane, Kile, Podger and Brown) CSIRO Publishing, Collingwood, Victoria.

Box‐Ironbark Silviculture Reference Manual 105

Kimmins, H. (1997). Balancing Act. Environmental Issues in Forestry, second edition. UBC Press, University of British Columbia, Vancouver. Kutt, A.S. (1994). Arboreal marsupials and nocturnal birds in thinned regrowth, unthinned regrowth and old lowland forest, East Gippsland Victoria. Australian. Forestry 57: 123‐130. Kutt, A., Thompson, B., Trumbull‐Ward, A. & Henry, S. (1995). Impacts of eucalypt regrowth thinning on flora and fauna values in lowland forest in East Gippsland Internal Report for the Department of Conservation and Natural Resources, Victoria, 31 pp. Larson E. (1965). Germination of Eucalyptus Seed. Forest Research Institute Leaflet No. 94. Commonwealth of Australia Forestry and Timber Bureau, 16 pp. La Sala, A.V. (2006). Pre‐commercial thinning and fertiliser enhance growth in young native Eucalyptus obliqua stands in Tasmania. Australian Forestry 69: 16‐24. LCC (1978). Report on the North Central Study Area. Land Conservation Council, Melbourne, Victoria. LCC (1983). Report on the Murray Valley Area. Land Conservation Council, Melbourne, Victoria. Loyn, R.H., Runnalls, R.G., Forward, G.Y., & Tyers, J. (1983). Territorial bell miners and other birds affecting populations of insect prey. Science 221: 1411‐13. Loyn, R.H. (1985). Ecology distribution and density of birds in Victorian forests. Chap 4 In Birds of the Eucalypt Forests and Woodlands: ecology, conservation and management (Eds Keast, A., Recher, H.F., Ford, H.A. & Saunders, D. Surrey‐Beatty, Sydney, New South Wales. 33‐46 pp. Loyn, R.H. (2004). Research for ecologically sustainable forest management in Victorian eucalypt forests. pp. 783‐806. In Conservation of Australia’s Forest Fauna, 2nd edn (Ed. D. Lunney), Royal Zoological Society of New South Wales, Mosman, New South Wales. Lutze, M. (1998). Establishment of E. tricarpa from planted seedlings in the lowland forests of East Gippsland. Forest Research Report No. 362, Forests Service, Department of Natural Resources and Environment, Victoria. Lutze, M. & Geary, P. (1998). Site Preparation. Native Forest Silviculture Guideline No. 6, Forests Service, Department of Natural Resources and Environment, Victoria, 50 pp.

106 Box‐Ironbark Silviculture Reference Manual

Lutze, M., Campbell, R. & Fagg, P. (1999). Development of silviculture in the native State forests of Victoria. Australian Forestry 62: 236‐244. Mac Nally, R. & Brown, G.W. (2000). Reptiles and habitat fragmentation in the Box‐ Ironbark forests of central Victoria, Australia: predictions, compositional change and faunal nestedness. Oecologia 128: 116‐125. Mac Nally, R. & Horrocks, G. (2000). Landscape‐scale conservation of an endangered migrant: the Swift Parrot Lathamus discolor in its winter range. Biological Conservation 92: 335‐343. Mac Nally, R., Bennett, A.F. & Horrocks, G. (2000). Forecasting the impacts of habitat fragmentation. Evaluation of species‐specific predictions of the impact of habitat fragmentation on birds in the Box‐Ironbark forests of central Victoria, Australia. Biological Conservation 95: 7‐29. Mac Nally, R., Bennett, A.F., Thomson, J.R., Radford, J.Q., Unmack, G., Horrocks, G. & Vesk, P.A. (2009). Collapse of an avifauna: climate change appears to exacerbate habitat loss and degradation. Diversity and Distributions 15: 720‐730. Marks, G.C., Fuhrer, B.A., & Walters, N.E.M. (1982). Tree Diseases in Victoria. Forests Commission Victoria, Handbook No. 1, 149 pp. Marks, G.C., Kassaby, F.Y. & Fagg, P.C. (1973). Dieback tolerance in Eucalyptus species in relation to fertilisation and soil populations of Phytophthora cinnamomi.Australian Journal of Botany 21: 53‐65. Marks, G.C. & Smith, I.W. (1991). The Cinnamon Fungus in Victorian forests – history distribution, management and control. Lands and Forests Bulletin No. 31, Department of Conservation and Environment, Melbourne, Victoria. 33 pp. Maron, M., Grey, M.J., Catterall, C.P., Major, R.E., Oliver, D.L., Clarke, M.J., Loyn, R.H., Mac Nally, R., Davidson, I. & Thomson, J.R. (2013). Avifaunal disarray due to a single despotic species. Diversity and Distribution 10: 1‐12. McDonald, B. (1999). Document on flowering provided to the Department of Natural Resources and Environment, attached to memo by Les Vearing dated 28/7/1999, Victoria. McKinty, J.A. (1969). Forestry in East Gippsland. Proceedings of the Royal Society of Victoria 82(1): 129‐139. Menkhorst, P.W. (1995). Mammals of Victoria ‐ distribution, ecology and conservation. Oxford University Press in association with the Department of Conservation and Natural Resources, Melbourne, Victoria, 359 pp.

Box‐Ironbark Silviculture Reference Manual 107

Minko, G. & Fagg, P.C. (1989). Control of some mistletoe species on eucalypts by trunk injection with herbicides. Australian Forestry 52: 94‐102. Moncur, M.W. & Boland, D.J. (1982). Floral morphology of Eucalyptus melliodora A. Cunn. ex Schau. and comparison with other eucalypt species. Australian Journal of Botany 37: 125‐135. Muir, A.M., Edwards, S.A., & Dickins, M.J. (1995). Description and conservation status of the vegetation of the Box‐Ironbark Ecosystem in Victoria. Flora & Fauna Technical Report No. 136, Flora and Fauna Branch, Rylah Research Institute, Department of Conservation and Natural Resources, East Melbourne, Victoria, 136 pp. Murray, M.D. and Lutze, M.T. (2004). Seed crop development in Eucalyptus obliqua and E. cypellocarpa in HEMS forests of East Gippsland. Research Report No. 387. Forestry Victoria, Department of Sustainability and Environment, Victoria. Murphy, S. & Forrester, D. (2008). Growth responses to thinning in E. tricarpa. Forest Research Report, School of Forest and Ecosystem Science, University of Melbourne, Victoria, 12 pp. (unpubl.) Murphy, S., Hateley, R. & Fagg, P. (2013). Low Elevation Mixed Species in Victoria’s State forests. Silviculture Reference Manual No. 3. Department of Environment and Primary Industries, Victoria, 158 pp. Naumann, I. (1991). Hymenoptera. In CSIRO, The Insects of Australia, Vol. II, Melbourne University Press, Carlton, Victoria, 916‐1000 pp. Neumann, F.G. & Collett, N.G. (1998). Review of seed‐destroying wasps of genus Megastigmus (Torymidae), with special reference to infestations in seed orchards of Tasmanian blue gum. Department of Natural Resources and Environment, Centre for Forest Tree Technology Report, Melbourne, Victoria. Neumann, F.G. & Kassaby, F.Y. (1986). Effects of commercial pesticides in seed‐coats on seeds and germinants of Eucalyptus regnans, and their potential as seed protectants in the field. Australian Forest Research 16: 37‐50. Newman, L.A. (1961). The Box‐Ironbark Forests of Victoria, Australia. Bulletin No. 14, Forests Commission Victoria, Melbourne, Victoria, 15 pp. NRE (1998). Box‐Ironbark Timber Assessment project (Bendigo Forest Management Area and Pyrenees Ranges). Forests Service Technical Report 98‐3. Department of Natural Resources and Environment, Melbourne, Victoria, 40 pp. NRE (1999). Tree Hollows in the Box‐Ironbark Forest ‐ Analyses of ecological data from the Box‐Ironbark Timber Assessment project (Bendigo Forest Management Area and

108 Box‐Ironbark Silviculture Reference Manual

Pyrenees Ranges). Forests Service Technical Report 99‐3. Department of Natural Resources and Environment, Melbourne, Victoria, 36 pp. NRE (2002). Proceedings of the 1999 South‐Eastern Australia Native Forest Browsing Workshop (Ed. O. Bassett), Forests Service, Department of Natural Resources and Environment, Victoria, 82 pp. Orscheg, C., Enright, N.J., Coates, F. & Thomas, I. (2011). Recruitment limitation in dry sclerophyll forests: regeneration requirements and potential density‐dependent effects in Eucalyptus tricarpa. Australian Ecology 36: 936‐943. Park, R.F., Keane, P.J., Wingfield, M.J., & Crous, P.W. (2000). Fungal diseases of eucalypt foliage. Chap. 9 In Diseases and Pathogens of Eucalypts (Eds. Keane, Kile, Podger and Brown) CSIRO Publishing, Collingwood, Victoria. Pederick, L.A. (1960). Some seed collection data from adjacent trees of Eucalyptus obliqua L’Herit. Forests Commission Victoria, Forestry Technical Papers No. 5, Melbourne, Victoria. Pederick, L.A. (1976). The genetic resources of the Victorian eucalypts. Bulletin No. 22, Forests Commission Victoria, 31 pp. Pederick, L.A. & Zimmer, W.J. (1961). The parasitic forest dodder‐laurel Cassytha melantha R.Br., Bulletin No. 12, Forests Commission Victoria, 16 pp. Perry, D.H., Lenz, M., & Watson, J.A.L. (1985). Relationship between fire, fungal rots and termite damage in Australian forest trees. Australian Forestry 48: 46‐53. Pigott, P., Wright, J. & Varcoe, T. (2008). Box‐Ironbark Ecological Thinning Trial ‐ Progress Report II, Parks Victoria, Melbourne, Victoria, 44 pp. Porter, J.W. (1978). Relationships between flowering and honey production of E. tricarpa, E. sideroxylon (A. Cunn.) Benth., and climate in the Bendigo district of Victoria. Australian Journal of Agricultural Research 29: 815‐829. Poynter, M. (2004). Management of Landings, Bark and Extraction Tracks. Native Forest Silviculture Guideline No. 11, Forestry Victoria, Department of Sustainability and Environment, Melbourne, Victoria, 25 pp. Poynter, M. & Fagg, P. (2005). Browsing Management. Native Forest Silviculture Guideline No. 7, Parks & Forests Division, Department of Sustainability and Environment, Melbourne, Victoria, 42 pp. Poynter, M., Fagg, P., Bassett, O., Slijkerman, C., & Lutze, M. (2009). Forest Recovery after Bushfire. Native Forest Silviculture Guideline No. 17, Forests & Parks Division, Department of Sustainability and Environment, Melbourne, Victoria, 55 pp.

Box‐Ironbark Silviculture Reference Manual 109

Pryor, L.D. & Johnson L.A.S. (1971). A Classification of the Eucalypts. The Australian National University, Canberra, ACT. Raison, J., Geary, P., Kerruish, B., Connell, M., Jacobsen, K., Roberts, E. & Hescock, R. (1995). Opportunities for more productive management of regrowth eucalypt forests: a case study in the E. sieberi forests of East Gippsland. Proc. 16th Biennial Conference of Institute of Foresters, Ballarat, Victoria, 31‐37 pp. Reid, N. & Yan, Z. (2000). Mistletoes and other Phanerogams Parasitic on Eucalypts. Chap 15. In Diseases and Pathogens of Eucalypts, (Eds. Keane, Kile, Podger & Brown) CSIRO Publishing, Collingwood, Victoria, 565 pp. Ritchie, T. (1977). The Eucalyptus Oil Industry in Victoria ‐ a brief study. Division of Forest Management, Forests Commission Victoria, 20 pp + Appendices (unpubl.). Roberts, B. (2001). Eucalypt Seed Coating. Native Forest Silviculture Guideline No. 5, Forestry Victoria, Department of Natural Resources and Environment, Victoria, 13 pp. Sebire, I.D. & Fagg. P.C. (2009). High Elevation Mixed Species in Victoria’s State forests. Silviculture Reference Manual No. 2, Department of Sustainability and Environment, Victoria, 112 pp. SEWPAC (2014) ‐ refers to the federal government website below (Department of Sustainability, Environment, Water, Population and Communities (Australia): http://www.environment.gov.au/cgi‐ bin/sprat/public/publicthreatenedlist.pl?wanted=fauna Silveira, C.E., Yen, A.L., Brown, G.W., Loyn, R.H., Lumsden, L.F., Bennett, A.F. & Hinkley, S.D. (1997). Fauna of the Box‐Ironbark study area. Report for the Land Conservation Council. Department of Natural Resources and Environment. Arthur Rylah Institute, Heidelberg, Victoria. Sivertsen, D. (1993). Conservation of remnant vegetation in the box and ironbark lands of New South Wales. Proc. 1992 VNPA Conference. The Victorian Naturalist 110(1): 24‐29. Slijkerman, C. (2007). Heathcote and Rushworth State Forests. Forest Notes FS0072, Department of Sustainability and Environment, Victoria, 6 pp. Smith, D.M., Larson, B.C., Kelty, M.J. & Ashton, P.M.S. (1997). The Practice of Silviculture: Applied Forest Ecology. 9th edn, John Wiley & Sons, New York, 537 pp.

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Smith, I.W., Marks, G.C., Featherston, G.R. & Geary, P.W. (1989). Effects of inter‐ planted wattles on the establishment of eucalypts planted on forest sites affected by Phytophthora cinnamomi. Australian Forestry 52: 74‐81. Smith, I.W. & Smith, D.I. (2003). Armillaria root rot: a disease of native and introduced trees. Forests Facts Sheet. Department of Sustainability and Environment, Victoria, 3 pp. Soderquist, T.R. (1993). Maternal strategies of Phascogale tapoatafa (Marsupialia: Dasyuridae). II. Juvenile thermoregulation and maternal attendance. Australian Journal of Zoology 41: 557‐576. Soderquist, T. (1999). Tree hollows in the Box‐Ironbark forest: analyses of ecological data from the Box‐Ironbark Timber Assessment in the Bendigo Forest Management Area and Pyrenees Ranges. Forests Service Technical Report 99‐3. Department of Natural Resources and Environment, Victoria, 35 pp. Stoneman, G.L. (2007). ‘Ecological forestry’ and eucalypt forests managed for wood production in south‐western Australia. Biological Conservation 137: 558‐566. Tolsma, A., Brown, G. & Cheal, D. (2010). The likely impacts of prescribed fire on the flora and fauna of Box‐Ironbark remnants. Proceedings of the Royal Society of Victoria: transactions. 122 (2): lxxxv‐xc. Traill, B.J. (1993). Forestry, birds, mammals and management in Box and Ironbark forests. Proc. 1992 VNPA Conference. The Victorian Naturalist 110: 11‐14. Tzaros, C. (2005). Wildlife of the Box‐Ironbark Country. CSIRO Publishing, Collingwood, Victoria, 256 pp. VNPA (2002). Victoria’s Box‐Ironbark Country: a field guide. 2nd edn, Victorian National Parks Association, Carlton, Victoria, 120 pp. Wallace, G.D. (1994). Eucalypt Seed Collection. Native Forest Silviculture Guideline No. 2. Department of Conservation and Natural Resources, Victoria, 38 pp. Wallace, G.D. & Fagg, P.C. (1995). Eucalypt Seed Sampling and Testing. Native Forest Silviculture Guideline No. 4. Department of Conservation and Natural Resources, Victoria, 20 pp. Wallace, G.D. & Fagg, P.C. (1999). Browsing in Victorian native State forests – results of the 1995 Statewide survey. Research Report No. 367. Forests Service, Department of Natural Resources and Environment, Victoria, 23 pp. Wang, Y., Hamilton, F., & Keenan, R. (2008). Modelling the competitive effects of forested edges and retained overwood on the dynamics and growth of native mixed

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species regrowth forests. Report prepared for the 2007/08 SFES‐DSE Research Program, Department of Forest and Ecosystem Science, University of Melbourne, Victoria, 51 pp. Watson, D.M. (2001). Mistletoe– a keystone resource in forests and woodlands worldwide. Annual Review of Ecology and Systematics 32: 219‐249. Watson, J.A.L. & Gay, F.J. (1991). Isoptera. In, The Insects of Australia Vol. I, CSIRO Melbourne University Press, Carlton, Victoria, 330‐347 pp. Weir, I.C.A. (1969). Studies of the Distribution and Development of Regrowth in a Selection Forest of Mixed Species Eucalypts. M.Sc. (For.) Thesis. University of Melbourne, Victoria, 193 pp. Weste, G. (1974). Phytophthora cinnamomi the cause of severe disease in certain native communities in Victoria. Australian Journal of Botany 22: 1‐8. Wilson, J. (2002). Flowering Ecology of a Box‐Ironbark Eucalyptus Community. Thesis submitted for the degree of Doctor of Philosophy. School of Ecology and Environment, Deakin University Victoria. Wilson, J. & Bennett, A.F. (1999). Patchiness of a floral resource: flowering of Eucalyptus tricarpa in a Box‐Ironbark forest. The Victorian Naturalist 116: 48‐53. Woodgate, P. & Black, P. (1988). Forest cover changes in Victoria, 1869‐1987. Department of Conservation Forests and Lands, Melbourne, Victoria. Yates, C.J. & Hobbs, R.J. (1997). Temperate Eucalypt Woodlands: A review of their status, processes threatening their persistence and techniques for restoration. Australian Journal of Botany 45: 949‐973. Wrigley, J. & Fagg, M. (2010). Eucalyptus Oil. Chap.25 In Eucalypts ‐ A Celebration. Allen & Unwin, Crows Nest, New South Wales, 187‐195 pp. Zimmer, W.J. & Grose, R.J (1958). Root systems and root‐shoot ratios of seedlings of some Victorian eucalypts. Australian Forestry 22 (1): 13‐18.

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APPENDIX A ‐ Prescriptions regarding Phytophthora

Draft22 prescriptions to minimise spread of Phytophthora cinnamomi (PC) in timber harvesting coupes in Box‐Ironbark areas ‐ DEPI October 2014

1. Spray down all vehicles and machinery with ‘Phytoclean’ before they enter and as they leave a coupe known to have P. cinnamomi. Spray where soil is likely to be attached, including wheels, side‐steps, mud flaps, wheel arches, etc.

2. In harvesting, do not remove more than 50% of the basal area.

3. Do not bring any gravel/dirt/rock into the coupe unless it is from a known PC‐ free source.

Conduct annual soil sampling/testing for P. cinnamomi at six points within the coupe. To be carried out by the Forest Officer, for two years after harvesting has ceased.

APPENDIX B ‐ Indices of Flowering Behaviour

Indices of flowering behaviour for five Box‐Ironbark eucalypt species found near Havelock and Rushworth (from Keatley & Hudson 2007).

The following table contain long‐term indices of flowering behaviour, for (1) probability (Pr) of commencement, (2) flowering intensity rank 1‐5, where 1 = zero flowering and 5 = widespread heavy flowering, (3) probability of monthly flowering, and (4) probability of monthly flowering cessation. Highlighted cells represent the month within which probability of start, finish, or flowering presence is highest, or which month flowering intensity peaked. n = number of flowering years. The highest values are highlighted in bold. These indices are based on data collected from two sites over a 30‐year period (1940‐ 70). The temporal sampling is excellent (likely the longest set of flowering observations for any eucalypt), however, only two sites are represented. These data are therefore a guideline for comparison with other sites at any point in time. Note that much of these

22 A State‐wide Standard Operating Procedure is being prepared and will replace this draft when available.

Box‐Ironbark Silviculture Reference Manual 113 data were confirmed against more recent studies by the same scientist (Keatley 1999), and also concur largely with studies undertaken elsewhere by others (e.g. Wilson 2002).

Flowering commencement (Pr) n Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Rushworth 14 0.43 0.07 0.43 0.07 E. tricarpa Havelock 27 0.04 0.19 0.04 0.41 0.22 0.07 0.04 Rushworth 16 0.25 0.06 0.19 0.06 0.13 0.25 0.06 E. leucoxylon Havelock 28 0.36 0.39 0.11 0.07 0.07 Rushworth 9 0.11 0.22 0.33 0.11 0.22 E. polyanthemos Havelock 27 0.04 0.11 0.15 0.48 0.22 Rushworth 15 0.07 0.47 0.20 0.27 E. melliodora Havelock 30 0.03 0.27 0.63 0.07 Rushworth 15 0.73 0.07 0.07 0.07 0.07 E. microcarpa Havelock 27 0.15 0.67 0.15 0.04

Flowering intensity (1‐5) n Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Rushworth171.241.471.473.183.453.59 2.55 2.60 2.35 0.36 0.19 0.19 E. tricarpa Havelock 27 0.04 0.30 0.50 1.20 1.93 2.11 2.22 2.07 1.56 0.52 0.12 0.04 Rushworth191.210.951.001.631.591.852.45 2.32 2.23 1.75 1.40 0.93 E. leucoxylon Havelock 32 0.75 0.20 0.23 0.70 1.70 2.19 2.27 2.55 2.61 2.52 2.22 1.59 Rushworth 12 0.15 0.50 0.92 1.31 1.46 1.42 1.19 1.12 E. polyanthemos Havelock 28 1.07 0.35 0.19 0.07 0.13 0.04 0.15 0.35 1.41 2.54 1.96 Rushworth 15 0.73 0.73 0.47 0.13 0.27 0.13 0.13 2.13 3.07 3.07 E. melliodora Havelock 31 3.15 2.19 1.29 0.17 0.07 0.03 0.03 0.37 1.78 2.88 Rushworth 16 2.88 2.75 3.00 1.95 1.14 0.86 0.53 0.42 0.42 E. microcarpa Havelock 27 0.15 1.63 2.70 2.43 1.35 0.44 0.09 0.04

Monthly flowering (Pr) n Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Rushworth 17 0.41 0.47 0.47 0.73 0.73 0.73 0.60 0.65 0.65 0.17 0.11 0.11 E. tricarpa Havelock 27 0.04 0.22 0.26 0.63 0.89 0.96 1.00 0.89 0.81 0.38 0.12 0.04 Rushworth190.470.370.370.570.520.650.73 0.68 0.64 0.55 0.50 0.40 E. leucoxylon Havelock 32 0.31 0.16 0.16 0.44 0.75 0.84 0.94 0.91 0.94 1.00 0.94 0.78 Rushworth 9 0.11 0.33 0.67 0.78 0.78 0.56 0.56 0.56 E. polyanthemos Havelock 28 0.43 0.14 0.14 0.07 0.11 0.04 0.11 0.25 0.67 0.89 0.85 Rushworth 15 0.40 0.40 0.13 0.07 0.11 0.06 0.06 0.53 0.71 0.94 E. melliodora Havelock 31 0.97 0.93 0.70 0.10 0.03 0.03 0.03 0.27 0.90 0.97 Rushworth 16 0.60 0.60 0.67 0.60 0.47 0.33 0.27 0.20 0.20 E. microcarpa Havelock 27 0.15 0.81 0.96 0.93 0.74 0.30 0.07 0.04

Flowering cessation (Pr) n Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Rushworth 16 0.13 0.06 0.69 0.06 0.06 E. tricarpa Havelock 26 0.12 0.08 0.42 0.27 0.12 Rushworth 16 0.06 0.06 0.13 0.13 0.08 0.13 0.13 0.13 0.19 E. leucoxylon Havelock 28 0.22 0.04 0.04 0.19 0.52 Rushworth 9 0.44 0.56 E. polyanthemos Havelock 28 0.29 0.07 0.07 0.07 0.04 0.07 0.46 Rushworth 12 0 0.25 0.17 0.08 0.00 0.50 E. melliodora Havelock 30 0.03 0.23 0.60 0.07 0.03 0.03 Rushworth 17 0.18 0.18 0.24 0.18 0.06 0.18 E. microcarpa Havelock 27 0.04 0.22 0.48 0.15 0.07 0.04

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APPENDIX C ‐ Sawlog Tree Specifications

Sawlog tree specifications (as at May 2014)

Product Sawlog Grade 1 Sawlog Grade 2 Firewood Criteria Min. length 2.4 m Min. length 1.8 m Min. length ‐ no min. Min. SEDUB 30 cm Min. SEDUB 15 cm Min. SEDUB 10 cm Minimum DBHOB* 44 cm (RIB) 28 cm (RIB) 18 cm (RIB) 38 cm (other species) 22 cm (other species) 12 cm (other species) Minimum (straight) 2.4 m 1.8 m No min. length length Maximum DBHOB for all sawlogs in Box‐Ironbark forest is 60 cm. *Minimum DBHOB estimates assume a bark thickness of 10‐12 cm for E. tricarpa (RIB), 3‐4 cm for other species, and an average taper along bole of 1.2 cm per metre.

APPENDIX D ‐ Silviculture Decision Support System

The Silviculture Decision Support System (SDSS) for Box‐Ironbark The Box‐Ironbark Silviculture Decision Support System (SDSS) is made up of a flow chart (Figure A, below) and these explanatory notes. The SDSS is also linked with this manual, particularly in chapters 4 and 5.

Planning Silviculture operations in Box‐Ironbark forests can be characterised initially by the products in demand; generally separated into sawlogs and firewood. The SDSS first asks what the primary product required is. This is because there are a number of product combinations possible, such as: 1. Sawlog driven with no other products (regrowth usually absent) 2. Sawlog driven with firewood taken as a secondary objective (regrowth present) 3. Firewood driven (pure regrowth) 4. Firewood driven, but with sawlogs taken as a secondary objective. At this planning stage, the products that can be taken could be influenced by the Forest Management Zoning of the coupe in question; that is, if a Special Management Zone, the products and volumes available will be restricted.

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A site inspection is required prior to harvesting, largely to ascertain if there is any regrowth, and this can be quantified for thinning purposes using pre‐harvest assessments (see section 5.2.4). Sawlogs Sawlogs can generally be harvested using Single Tree Selection (STS, see section 5.1), Group Selection (GSE, see section 5.2), or Coppice with Standards (CWS, see section 5.3). The difference is that stands suitable for CWS have a complex structured mix of regrowth, potential sawlogs and sawlogs ready for harvest. Each CWS structural element needs careful management to ensure their most effective use or retention, and section 5.3 provides guidance. When applying CWS, maintain at least the minimum basal area of 8 m2/ha to fulfil current habitat retention requirements. During coupe reconnaissance or pre‐harvest assessments, ascertain if there are unstocked gaps that should be stocked. Although the SDSS addresses this questions under ‘Harvesting’, it is helpful to plan to use Group Selection at this early stage if appropriate. Firewood Thinning is undertaken to produce firewood where regrowth is adequate and other site requirements are fulfilled (see section 5.4, and specifically Table 13 for guidance). The SDSS allows for poorer quality sites to be thinned down to a retained basal area below the NFSG recommendations (below 8 m2/ha to 4‐5 m2/ha), and this should be ascertained during the planning stage. Thinning lower quality sites is not usually a priority, but can enable some stand improvement work to be undertaken while also helping to meet heavy firewood demands when present.

Harvesting Thinning Where sawlogs are also present, the SDSS recommends the stand be managed using CWS. This can occur either at the current cutting stage if Grade 2 sawlogs are available and would release Standards from competition if harvested. However, note that all Grade 2 sawlogs with further growth potential should be retained. Otherwise, undertake a standard thinning operation according to section 5.4. It is assumed that most operations will be commercial, requiring firewood specifications to be fulfilled. Pre‐commercial thinning is possible – see section 5.5.

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Sawlogs If coppice is present of size suitable for firewood and/or other minor products, the SDSS recommends harvesting according to CWS principles. Age is less of an issue, with product specifications driving the decision of what forest elements to thin/harvest. Be guided by section 5.3. Otherwise, plan to undertake sawlog harvesting using Single Tree Selection (section 5.1) according to product specification (Appendix C). If gap regeneration is an objective, undertake Group Selection where appropriate in readiness for regeneration operations. Gap widening may be required to create a competition‐free zone for regeneration (section 5.2). As a guide, if there are three or more gaps 20+ m in diameter then plan for seedling regeneration works.

Regeneration Coppice Rely on coppice where STS has taken place in between any gaps. However, where gaps are widened, cut stumps may also create coppice and may therefore require herbicide treatment to maintain the reduction in competition achieved by gap widening, and required for seedling regeneration. Seedlings Refer to section 5.2.4 for guidance with seedling regeneration. It is a priority to create an ash bed by slash‐burning if possible, as this has shown to be more successful for Red Ironbark regeneration. Otherwise, undertake soil disturbance and sow according to section 5.2.4.

Monitoring Monitoring in Box‐Ironbark operations is straightforward. Although not explicitly shown on the SDSS, monitoring basal area throughout the harvesting operation is critical to ensure basal area targets are met. Otherwise, final post‐thinning assessments (see NFSG 15) and stocking surveys (see NFSG 10) are the only assessments required as shown on the SDSS. In particular, refer to sections 5.1.5 and 5.4.4 in this manual for guidance regarding performance measurement.

Please refer to the next page for the SDSS flow chart.

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APPENDIX E ‐ Habitat prescriptions

Prescriptions to maintain habitat in timber harvesting areas (Bendigo FMA and Box‐Ironbark forests in the Midlands FMA). Excerpt from Management Standards and Procedures for timber harvesting operations in Victoria’s State forests 2014 (DEPI 2014c).

4.1.3 Bendigo FMA and Box‐Ironbark forests in the Midlands FMA. 4.1.3.1 Permanently retain: (a) all trees (both standing dead or living) greater than 20 cm DBHOB with visible hollows where safe and practicable to do so. These trees may count towards retention requirements in clause (b) and (c); (b) at least 10 living trees per hectare between 30 cm and 39.9 cm DBHOB; (c) where they exist: i) 2 living trees per hectare between 40 cm and 49.9 cm DBHOB inclusive; and ii) 2 living trees per hectare between 50 and 59.9 cm DBHOB inclusive. non‐merchantable trees with healthy crowns should be preferentially retained; (d) all trees greater than 60 cm DBHOB in high quality sawlog harvesting operations; (e) all trees greater than 40 cm DBHOB in low quality sawlog and firewood harvesting operations; (f) within SMZ’s, all trees greater than 40 cm DBHOB in high and low quality sawlog and firewood harvesting operations; (g) all standing dead trees greater than 40 cm DBHOB; (h) all living Yellow Box, Fryers Range Scent‐bark and Bealiba Ironbark trees. These trees may count towards retention requirements. 4.1.3.2 A whole of coupe approach should be adopted (numbers averaged over coupe area) to ensure that the best habitat trees are retained, including where these occur in groups. 4.1.3.3 Firewood harvesting within a SMZ must be managed to ensure coarse woody debris levels are not reduced below pre‐harvest levels. 4.1.3.4 All log sections larger than 40 cm diameter with hollows larger than 10 cm diameter must be retained.

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4.1.3.5 The period between the next and subsequent sawlog harvesting operations will be at least 25 years to allow recruitment across all habitat classes. Habitat trees intended for permanent retention will not be permanently tagged or labelled. It is expected that these trees will be evident from their form.

NOTE The residual forest basal area after harvesting (thinning or single tree selection) will not be less than 8 square metres per hectare, unless specifically authorised for extraordinary circumstances such as fire salvage, forest health or public safety. This means that the numbers retained in a harvested stand may range from 30 ‐150 trees per hectare, depending on the mix of small, medium and large trees. In all sawlog Grade 1 harvesting operations, coupe boundaries must not be varied from that specified on the Forest Coupe Plan Map. Timber harvesting is permitted within the SMZ for Ecological Vegetation Class (EVC) 175 where it can be demonstrated that values will not be impacted; harvesting will be to EVC benchmark standards. Timber harvesting is also permitted within SMZ for historic sites according to DEPI protocols for management of cultural heritage sites in State forest in the Bendigo FMA, which allows forestry activities that do not impact on the relic or historic fabric.

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Acknowledgements

The staff and employees of Department of Environment and Primary Industries (DEPI) who have contributed to the preparation of this manual are gratefully acknowledged. In particular the authors would like to thank: Those who commented on or edited draft parts of this manual  Judy Alexander, Program Manager, Forest Management, Gippsland, DEPI  Paul Bates, District Manager, Murray Goldfields, Maryborough, DEPI  Robert Walters, Manager, Forest Industries Policy, DEPI  Justin Wong, Senior Policy Analyst, Forest Industries and Game, DEPI  Boyd Eggleston, Policy Analyst, Forest Industries and Game, DEPI  Marie Keatley, Phenologist, DFES, Melbourne University  Richard Loyn, Wildlife Scientist, Eco Insights  Fred Neumann, retired Forest Entomologist  David Smith, Forest Pathologist, Scoresby, DEPI  Ian Smith, Bushbury Forest Pathology Services

Those who supplied diagrams and photographs:  Owen Bassett ‐ Figures 1, 3, 8, 9, 11c, 17a, 18, 19, 23a, 24, 25, 26  Bernie Robb ‐ Figure 2 (Box‐Ironbark map)  W, H. Walter, artist ‐ Figure 4. Courtesy of National Museum, Victoria  E. J. Semmens collection (Beechworth Forestry Museum) ‐ Figures 5, 6, 7. Thanks to Brian Fry for accessing these  Peter Fagg ‐ Figures 10, 14, 15, 16, 17b, 23b, 27, 28a  Peter Menkhorst ‐ Figures 11a, 11b  Jerry Alexander ‐ Figure 12  Richard Loyn ‐ Figure 13  Marie Keatley – Figure 20  Glenn Dooley ‐ Figure 21  Cam Paterson ‐ Figure 22  Paul Bates ‐ Figure 29

The authors, Peter Fagg and Owen Bassett, are consultants for Forest Solutions Pty Ltd.

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Glossary

Age classes Areas or stands of trees originating in a defined year or period of years. Backlog regeneration Regeneration of coupes that have failed to regenerate adequately after the initial regeneration attempt. Basal area The sum of the cross‐sectional areas measured at breast height of the trees in a given stand. Usually expressed as square metres per hectare (m2/ha). Biodiversity (biological The variety of all life forms; the plants, animals and diversity) micro‐organisms, their genes and the ecosystems they inhabit. Biomass The total mass of all living matter in a defined area. Bole The trunk or main stem of a tree. Breast height 1.3 m above ground level ‐ for tree diameter or girth measurement. Clear‐felling A silvicultural system in which most live trees, not required for environmental purposes, are harvested in one operation. Cineole The most important component of eucalyptus oil, varying between 50% and 90% depending on the species. It has mild anti‐bacterial and anti‐microbial properties. Code of Practice for Set of principles, procedures, guidelines and standards Timber Production that specify minimum acceptable environmental practices in harvesting and associated forest management operations. Co‐dominant Tree with a crown at the general level of the canopy; has medium‐sized crown. Coppice (coppicing) 1. n. Shoots/stems arising from previously dormant buds generally arising from cut or broken stumps 2. v. to produce coppice, or to cut or remove coppice from a stump

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Coupe A temporary planning unit of forest used to identify the area designated for harvesting of forest produce and for regeneration activities. Crown The main canopy of a tree, including the main branches and leaves. Crown, primary The main, original framework of branches, twigs and leaves that has not been subject to damage. Crown, secondary The framework of branches, twigs and leaves that has replaced the (damaged) primary crown. Damage Any injury caused to trees and other forest plants caused by harvesting activities, fire, wind, insect attack or other natural or human induced causes. Damping‐off Death of small seedlings due to attack by fungi in moist conditions. DBHOB The diameter of the main stem of a tree measured at breast height (1.3 m) and over the bark. DELWP Department of Environment, Land, Water and Planning DEDJTR Department of Economic Development, Jobs, Transport and Resources (also abbreviated ECODEV) DEPI The Victorian Government former Department of Environment and Primary Industries. It was responsible for managing all State forests for a variety of commercial and non‐commercial uses. Decay The decomposition of wood by fungi. Defect A natural feature in a log that may affect the structural soundness and quality of the timber. Defoliation Temporary or permanent loss of leaves. May be caused by fire, insects, drought or herbicides. Diameter The width measurement of trees or logs, usually made at breast height (1.3 m above upper ground level). Dieback Death of branches or tips of a tree, associated with disease, insect attack or fire.

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Dominant (tree) A tree with a crown extending above the general level of the canopy, larger than the average tree in the stand, which has a well‐developed crown. Duplex Type of soil profile with distinct A and B horizons. Environment Conservation A body that advises the Victorian Government on the use Council (ECC) of public land. It investigates issues on designated areas, taking account of resource use, social needs and environmental issues. Ecological Vegetation Class The components of a vegetation classification system. (EVC) They are groupings of vegetation communities based on floristic, structural and ecological features. Ecosystem All the organisms (including plants and animals) in a particular area together with the physical environment with which they interact. Ectomycorrhizae A non‐pathogenic association of a fungus with the roots of a tree, in which the fungus forms a sheath around a fine root and enhances nutrient uptake. Epicormic shoot/growth Shoot arising from a dormant bud in the stem or branch (epicormics) of a woody plant, often following defoliation by fire or insects. Even‐aged forest/stand Forest predominantly of the one age. Usually originating as a result of an intense burn or harvesting activity. Fauna A general term for animals (including reptiles, birds marsupials and fish). Felling Manual or mechanical pushing over or cutting down of standing trees. Felling cycles The time between successive (usually selection) harvesting events in a particular area. Flora A general term for plants of a particular area or time. Forest Management Area A territorial unit for planning and management of State (FMA) forests in Victoria. Currently Victoria is divided into 15 FMAs as defined in the Forests Act 1958.

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Forest Management Plan A plan dealing with strategic and operational issues of (FMP) forest management prepared for a specific region and integrating environmental and commercial objectives. Forest Management Zone Delineated forest area of similar attributes to which (FMZ) particular Departmental strategies and specific prescriptions may apply. There are three types of zones: the Special Protection Zone, Special Management Zone and General Management Zone. Forest type Classification of forests according to; (a) their life form and height of the tallest stratum, and the projected foliage cover of the tallest stratum, or (b) their main component species +/‐ elevation. Forests Commission Agency of the Victorian Government responsible for management of State forests in the period 1919‐1984. Frost heave The lifting of soil as a result of ice formation and expansion in frozen soil. In the process, small seedlings may be pushed out of the soil and thereby killed. Frost kill Death of plant tissue or a whole seedling caused by low temperatures. Genetics The science of heredity. Germinative energy The rate at which a seed lot germinates. Also known as ‘seed vitality’. Growth stages A system used to describe the life cycle of trees based mainly on crown form – the main ones being seedling, sapling, pole, spar, mature and senescent. Habitat trees A tree identified and protected from harvesting to provide habitat or future habitat for wildlife. Harvesting The felling of trees; cutting, snigging, preparing, sorting, loading or carting of forest produce from trees which have been felled or which are fallen. Height The height above upper ground level to the top of a tree crown.

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Hollow An opening in the trunk or branches of a tree often formed after a branch dies and falls off. Increment The increase in volume, diameter, height or other measure of individual trees or stands during a given period. Inflorescence buds An early stage of eucalypt flowering in which bud clusters are enclosed within a bract. Kino (veins) Reddish, phenolic, viscous fluid found in veins or pockets of wood of eucalypts, generally as a result of injury or stress. Landing, log An area within a coupe where parts of trees are sorted, processed and loaded for transport. Lignotuber A woody swelling at the base of the stem on many eucalypt species, at or below the soil level, bearing dormant buds. Litter fall Organic material (mainly leaves, twigs and bark) that falls to the forest floor. Mature forest A description of a forest stand and/or individual trees where the tree crowns are well foliated and rounded. The height and crown development of the trees has effectively ceased (compared with regrowth) but decline of the crown has not yet significantly begun (as in the senescent or over‐mature growth stage). Mean Annual Increment The total wood increment up to a given age divided by (MAI) that age (m3/ha). Merchantable Tree or part of a tree, from which saleable forest produce can be obtained. Mixed species forest Forest which has two or more eucalypt species commonly found within the canopy. Generally consisting of Peppermint, Messmate, Gum or Bark species. Does not include Ash, Red Gum or Box‐Ironbark forests. Mixed‐age stand A stand where trees of at least two ages are present.

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Nutrient capital The total amount of various elements needed for plant growth held in the part of the soil profile that is accessed by root systems. Old growth forest Forest which contains significant amounts of its oldest growth stage — usually senescent trees — in the upper stratum and has been subjected to any disturbance, the effect of which is now negligible. Operculum The cap on the top of an unopened eucalypt flower bud. Over‐mature A growth stage of a forest stand or individual tree that is characterised by a declining crown leaf area and irregular crown shape due to a loss of branches and epicormic growth. Overwood Mature trees that are taller than trees at a lower level. Can refer to seed trees, habitat trees etc, left standing after harvesting. Parks Victoria (PV) The Victorian Government agency responsible for managing and protecting all national parks and other conservation reserves. Pathogen A disease‐producing organism, such as a fungus or a virus. Pipe Defect in the core of a sawlog, where wood has been eaten away by fungi and/or insects. Pollination The transfer of pollen from an anther to a stigma in a flower. Pre‐commercial thinning The manual or mechanical thinning of a young dense stand in which the trees are not merchantable. Provenance The original geographic source of seed or other genetic material. Psyllid A type of sap‐sucking insect which lives under a protective covering called a lerp. Severe infestation causes extensive foliage damage.

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Regeneration n. The young regrowth of trees and other vegetation following disturbance of the forest such as timber harvesting or fire v. Renewing the forest by natural or artificial means. Reforestation The re‐establishment of a stand of trees by planting or sowing (with species native to the locality) on previously cleared or poorly forested land. Regrowth crown Trees with narrow, conical crowns with relatively high individual crown densities. Remedial regeneration (See backlog regeneration) Ring‐barking Removal of a band of bark around a tree in order to kill it. Ripping Breaking up compacted soil by pulling a ripping‐tyne behind a tractor. Root grafting (fusion) The joining of roots so that water and nutrients can move from one tree to the other. Rotation The planned number of years between the regeneration of a forest stand and its final harvesting. Salvage harvesting Harvesting of forest produce to recover a resource that would otherwise be lost as a result of damage by fire, pests or disease. Sawlog A log considered suitable in size and quality for producing sawn timber. Sawmilling Conversion of logs into sawn timber by running them through a series of saws (in a sawmill). Seedbed The soil on which seeds are sown or fall, and germinate in. Seed dormancy The condition of seeds in which they will not germinate even in apparently favourable conditions. Dormancy can be broken by a variety of treatments, such as moist cold, scarification or heat. Seed crop density A measure of the potential availability of seed (via capsules) held in a tree or a stand.

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Seed longevity The length of time that a seed or batch of seed retains a reasonable level of viability. Seed tree A tree left standing following harvesting to naturally regenerate the site by seed released from the crown. Seed viability The number of seeds that will germinate per unit weight of seed, e.g. no./kg. Seedling percent The percentage of seeds sown which germinate and become established seedlings at a given period (usually 12 months) after sowing/seedfall. Selection system An uneven‐aged silvicultural system involving the felling of selected mature trees at intervals over the rotation. Individual trees = single tree selection. Small patches of trees = group or gap selection. Silviculture The science and practice of managing forest harvesting, establishment, composition and growth to achieve specified objectives. Silvicultural system A process describing the techniques used to manage tree establishment and tending though one life cycle or rotation. Single tree selection (See selection system) Site preparation Preparation of the ground to provide conditions suitable for regeneration by sowing seed or by planting seedlings. Site quality The potential of the site to grow trees/timber. A function of soil quality, rainfall and aspect. Often measured as the height of a stand of trees at a given age. Skeletal Type of soil profile in which the layers are thin and rock is common at or near the surface. Slash Tree and other plant debris left on the ground as a result of forestry practices, e.g. timber harvesting, pruning, road construction, etc. Slash includes material such as leaves, twigs, branches, bark, shrubs and non‐merchantable timber.

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Sowing rate The rate at which seed is sown, usually in terms of either number of seeds per hectare or weight of seed per hectare. Stand A group of trees in a forest that can be distinguished from other groups on the basis of uniformity of age, species composition or condition. Usually at least one hectare in size. State forest A form of public land tenure in Victoria; managed for biodiversity, cultural heritage, forest products (including timber), catchment protection, recreation, research and education. Stem injection The insertion of herbicide into a cut or notch made in the trunk of a tree in order to stress or kill the tree. Stocking The density of any given forest stand, which can be expressed as: the number of trees per hectare, or the basal area per hectare, or the percentage of survey plots which contain acceptable stems. Stratification The treatment of seeds by cold and moist conditions for a period of time in order to break dormancy. Suppressed (tree) A tree with a crown entirely below the general level of the canopy. Synchrony The level to which peak flowering intensity is matched between neighbouring trees (site level) or forest stands (landscape level). Taproot The main root growing downwards into the soil and giving off lateral roots. Thinning The removal of part of a stand, with the aim of increasing the growth rate and/or health of the retained trees. Timber A general term used to describe (a) standing trees or felled logs before their processing into forest produce, and (b) natural or sawn wood in a form suitable for building and other purposes.

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Timber harvesting The snigging, preparing, sorting, loading or carting of trees or parts of trees which have been felled or which are fallen. Umbellate buds Eucalypt flower buds which occur in an umbel or cluster. Understorey The layer of vegetation that grows below the canopy formed by the tallest trees in a forest. Working circle A forest management unit, comprising a geographical area (such as several forest blocks) in which timber resources are assessed and managed on a sustainable basis.

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Index

biological control, 29, 35, 39 A Blue Box. See E.baueriana Blue Mallee. See Eucalyptus polybractea aboriginal tribes, 10 Box Mistletoe. See Amyema miquelii Acacia pycnantha, 21, 22 Box‐Ironbark Timber Assessment Survey, 40 agriculture, 11, 12, 92 Brisbane Ranges, 4, 9 clearing, iii, 3, 11, 12, 27, 31, 86 browsing, 36, 41, 42, 62, 63, 70, 76, 79, 82, grazing licences, 12 94, 96 squatters, 11 Browsing Indicator Plots, 79 Aireys Inlet, 4 Browsing Risk Assessments, 96 Amyema miquelii, 23, 38 control works, 36 Amyema pendula, 23, 38 budding and buds. See flowering Anakie, 8, 9 apiary, 16 C bee sites, 17 beeswax, 17 Cassytha melantha, 18, 36, 76, 79 nectar, 10, 16, 23, 24, 25, 28, 43, 47, 49, control of C. melantha, 38, 76 51, 68, 71, 91 non‐eucalypt hosts, 37 Armillaria luteobubalina, 34 Castlemaine, v, 4, 6, 7, 8, 11, 13, 17, 32, 34 Australian Capital Territory, 44 charcoal production. See timber industry, Avoca, 7, 31, 32, 55 Chiltern, 1, 4, 8, 13, 16, 40, 41 Christmas Hills, 4 B Cinnamon Fungus. See Phytophthora cinnamomi Bairnsdale, 4 climate, 7, 9, 33, 34, 44, 59 basal area, 6, 62, 64, 73, 74, 75, 77, 78, 81, drought, 7 82, 83, 84, 90, 112, 115, 116, 120, 130 frosts, 8, 61, 62 basal area gauge, 83 rainfall, 7, 8, 9, 31, 35, 41, 46, 61, 62, 71, Reference Basal Area, 74, 77, 89 88 Bealiba, 13, 35, 77, 119 storms, 33, 73 bee‐keeping. See apiary temperature, 8, 56, 59, 60 Bendigo, iv, v, 1, 4, 5, 7, 8, 10, 11, 14, 15, tornadoes, 32 16, 17, 19, 32, 35, 37, 44, 45, 46, 50, 51, coarse woody debris, 77 63, 71, 77, 86, 87, 119, 120 Code of Practice for Timber Production, 67 biodiversity research, 20 community engagement, 67 birds, 13, 23, 25, 26, 27, 30, 35, 38, 44, 77, coppice, 7, 11, 14, 31, 32, 37, 38, 40, 42, 53, 90, 91 60, 61, 62, 64, 68, 70, 73, 74, 76, 77, 78, conservation status, 27 79, 80, 81, 82, 85, 86, 90, 116, 122 frugivores, 26 coppice control, 64 granivores, 25 Coptotermes. See termites insectivores, 25, 26 Creswick, 19 Mistletoebird, 23, 26, 38 nectarivores, 16, 25, 47, 53 seasonal migrations, 27 D Swift Parrot, 23, 27, 50 Blackberry, 39 Dargile, 64, 83 disease, 33, 35, 123, 127

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Brown Rot, 34 Ecological Vegetation Classes, 3, 4 Cinnamon Fungus, 33, 34 ectomycorrhizae, 66 Honey Fungus, 34 Edenhope, 4 leaf diseases, 34 Environment Conservation Council, 5, 10, Mycosphaerella, 34 15, 124 White Pocket Rot, 34 environmental weed species, 39 White Rot, 34 epicormic shoots, 32, 33, 35, 65 Dodder‐laurel. See Cassytha melantha Established Seedling Surveys, 96 Doratifera vulnerans. See eucalypt oil, 14, 15 invertebrates:mottled cup moth history, 7, 15, 33, 101 Drooping Mistletoe. See Amyema pendula production, 14, 15, 17, 43 dryland salinity, 31 Eucalyptus crebra, 36 Dunolly, 4, 7, 16, 35, 41, 50 Eucalyptus polybractea, 14 European Rabbit. See Oryctolagus cuniculus E F E. albens, 3, 5, 25, 30, 55 E. aromaphloia, 77 fauna, 1, 20, 23, 29, 38, 43, 51, 68, 71, 72, E. baueriana, 5 77, 82, 87, 90, 91 E. bosistoana, 5, 12 conservation measures, iii, 1, 15, 27, 67, E. camaldulensis, 12, 24, 25, 26 68, 69, 70, 71, 72, 77, 79, 82, 85, 87, E. cladocalyx, 17, 74 88, 91 E. drepanophylla, 36, 61 fencing, 18, 36, 63, 79, 93 E. goniocalyx, 1, 3, 31, 59, 92, 94 fire, 9, 20, 31, 32, 33, 36, 55, 61, 62, 65, 72, E. leucoxylon, 1, 3, 4, 9, 10, 16, 17, 25, 29, 73, 76, 78, 79, 89, 120, 123, 124, 128 30, 32, 34, 35, 38, 41, 46, 47, 49, 51, 52, bushfires, 9, 31, 40, 92 54, 56, 58, 59, 81 negative impact, 32 E. macrorhyncha, 3, 6, 9, 31, 34, 59, 92 Prescribed (or fuel reduction burning, 32 E. marginata, 71 fire ecology studies, 20 E. melanophloia, 54 firewood, v, 12, 13, 14, 17, 39, 77, 78, 80, E. melliodora, 3, 5, 16, 34, 38, 46, 47, 49, 81, 83, 84, 85, 87, 114, 115, 116, 119 54, 55, 58, 59, 77, 92, 94 flora E. microcarpa, 1, 3, 6, 10, 12, 15, 16, 17, 18, environmental weed species, 22 23, 30, 35, 37, 38, 40, 41, 42, 51, 52, 55, orchids, 21 58, 59, 81, 92 rare or threatened, 21, 74 E. polyanthemos, 3, 5, 12, 15, 16, 23, 24, 29, understorey species, 21, 22, 90 31, 34, 38, 41, 46, 51, 52, 54, 55, 58, 59, Flora and Fauna Action Plans, 74 81, 92 flowering, 9, 17, 18, 20, 23, 25, 28, 29, 43, E. sideroxylon, 3, 8, 25, 29, 31, 34, 38, 40, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 45, 58, 59 57, 58, 71, 112, 126, 130 E. tricarpa, 1, 3, 4, 5, 6, 9, 10, 12, 14, 15, 16, budding and flower reports, 45 17, 18, 19, 20, 25, 30, 31, 33, 35, 37, 38, flowering period, 48, 50, 51 40, 41, 42, 44, 45, 46, 47, 48, 49, 50, 51, flowering studies, 43 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 64, flower‐life, 49 75, 77, 81, 83, 86, 92, 94, 96, 114 intensity, 32, 44, 48, 49, 51, 52, 53, 57, summer‐flowering, 51 64, 67, 73, 112, 130 winter‐flowering, 10 pollination, 17, 29, 43, 47, 48, 49, 52, 58 East Gippsland, 5, 12, 35, 44, 45, 50, 53, 55, synchrony, 44, 48, 51, 53, 58 65, 72, 96 time of flowering, 48

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Forest Coupe Plan, 74, 120 Heathcote, 4, 7, 12, 19, 29, 32, 36, 41, 64 Forest Management Area, iv, 5, 14, 77, 124 Heathy Dry Forest, 4, 5, 22 Forest Management Plans, 67 Heathy Woodland, 4 management zones, 67 Heyfield, 4, 7, 9, 41 Forests Commission, v, 13, 16, 18, 19, 44, hollows in trees, 13, 23, 24, 26, 30, 71, 72, 45, 60, 125 77, 87, 88, 119 frogs, 23, 29, 91 honey, 1, 17, 18, 43, 48, 49, 51, 53, 71, 77 Fryers Range Scent‐Bark. See E. honey production. See apiary aromaphloia honeyeaters. See birds:nectarivores Fryerstown, 34 Hydrology, 31 fuel reduction burns, 62 catchments, 1, 31, 70, 71 fungi, 34, 35, 39, 66, 85, 123, 127 recharge areas, 31

G I

General Management Zone, 71, 125 Inglewood, 4, 7 genetic factors, 9 invertebrates, 20, 29, 30 adaptive traits, 9 ant, 30 morphological variation, 9 Gumleaf Skeletoniser, 34, 35 geology, 30 Mottled Cup Moth, 34 Gippsland, 1, 4, 5, 55 psyllids, 35 Gippsland Grey Box. See E. bosistoana wasps, 35 Glenmona, 1 Golden Wattle. See Acacia pycnantha J Goldfields Bioregion, 2, 3 Gorse, 22, 39 Jarrah. See E. marginata Grassy Dry Forest, 4, 22 Great Dividing Range, 4, 7, 9, 21, 28 K Grey Box. See E.microcarpa Grey Ironbark. See E. drepanophylla Killawarra, 4, 6 growth, 6, 7, 19, 32, 33, 35, 36, 38, 41, 46, Kingower, 35 61, 63, 64, 65, 66, 70, 75, 78, 81, 86, 91, Kooyoora State Park, 30 115, 124, 127 age classes, 72, 80 L annual volume increment, 63 crown development, 65, 126 Land Conservation Council, 10 diameter, 6, 7, 24, 36, 38, 63, 65, 77, 81, land use determinations, 10 90, 119, 122, 123, 126 regional parks, 5, 10 edge effect, 70 landscape management, 72 growth rates, 63 lignotuber, 32, 41, 42 height, 3, 7, 37, 55, 64, 65, 70, 75, 76, lignotuberous seedlings, 40, 42 122, 125, 126, 129 Long‐leaved Box. See E. goniocalyx inverse J‐curve, 81

H M habitat trees, 64, 72, 75, 76, 78, 81, 84, 89, 119, 127 Majorca, 32, 45 Havelock, 45, 46, 49, 50, 51, 52, 112 mammals, 13, 23, 24, 30, 77, 90, 91

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Antechinus, 24, 25 Red Box. See E. polyanthemos Brush‐tailed Phascogale, 23, 24, 25 Red Ironbark. See E.tricarpa gliders, 23, 24, 25 Red Stringybark. See E. macrorhyncha marsupials, 24 reforestation, 10, 92, 93 Management Procedures, 71 regeneration, 7, 9, 10, 13, 18, 19, 40, 42, Maryborough, 4, 7, 8, 17, 32, 35, 41, 44, 55, 44, 53, 54, 55, 56, 60, 61, 62, 69, 70, 72, 61 73, 74, 76, 77, 78, 79, 82, 85, 92, 94, 116, mining, iii, 11, 12, 32, 93 122, 128 Mistletoe, 22, 38 coppicing, 9, 122 control of mistletoe, 38 protection of, 1, 60, 69, 76, 78, 79, 82, mistletoes, 25, 88 94, 96 Monocalyptus, 9, 33 seedling, 7, 9, 31, 33, 36, 37, 40, 41, 44, Mt Raymond, 4 53, 55, 59, 60, 61, 62, 65, 73, 74, 76, Mt Taylor, 4 77, 78, 92, 95, 116, 125 Mugga Ironbark. See E. sideroxylon seedling percents, 62 vegetative reproduction, 9 N Regional Forest Agreements, 67 rehabilitation, 92, 93 Narrow‐leaved Ironbark. See Eucalyptus site preparation, 76, 78, 82, 95, 129 crebra reptiles, 28 Nature Conservation Reserves, 5 skinks, 28 north east Victoria, iv, 4, 5, 6, 16, 72, 92 snakes, 28 Nowa Nowa, 12 River Red Gum. See E.camaldulensis nutrition, 30, 66 root systems, 18, 41, 127 nutrient cycling, 29 roots, 30, 33, 34, 40, 41, 65, 66, 124, 128, phosphorus, 66 130 rotation, 70, 72, 74, 78, 80, 81, 129 O Royal Commission, 13 Rushworth, 1, 4, 7, 8, 12, 13, 15, 17, 18, 19, Orbost, 4 33, 44, 49, 50, 60, 75, 112 original forests, 10 Oryctolagus cuniculus, 36, 62 S Otway Range, 5 overwood, 14, 40, 61, 62, 63, 64, 96 salvage of timber, 32, 68, 73, 120 Sandon State Forest, 38 P sawlog tree specifications, 114 sawlogs, 17, 63, 68, 75, 77, 78, 81, 83, 84, Perrin, George, 12 94, 114, 115 Phytophthora cinnamomi, 9, 33, 112 seed Pilot National Park, 4 collection, 10, 53, 55, 56, 57, 58, 79 planting, 40, 92, 93, 94, 96, 128, 129 dissemination, 19, 43, 53–55 pre‐harvest assessments, 115 dormancy, 57, 58, 128, 130 Puckapunyal, 4 germination, 18, 19, 20, 52, 55, 58, 59, Pyrenees, 4 60, 61, 94, 96, 102 Pyrete Ranges, 4 harvesting by ants, 60 seedfall, 9, 44, 53, 55, 60, 61, 79, 129 R storage, 31, 49, 55, 56, 57 viability, 53, 57, 58, 93, 129 railways, 12 vitality, 57, 58, 125

136 Box‐Ironbark Silviculture Reference Manual seed production, 10, 18, 36, 43, 44, 52, 53, survey procedure, 77 54, 55, 56, 57, 58, 60, 128 strategic planning, 67 capsules, 36, 40, 43, 53, 54, 55, 56, 57, stumps, 23, 24, 29, 42, 60, 64, 68, 74, 76, 58, 128 78, 82, 83, 85, 86, 88, 90, 94, 116, 122 chaff, 54, 59 herbicide treatment of, 64, 79 fungal damage, 54 Sugar Gum. See E. cladocalyx seed crop quantities, 65 Swamp Wallabies, 70, 79, 82 seed forecasting, 51 Symphyomyrtus, 9, 33, 54 seedbed, 33, 41, 61, 62, 73, 76, 78, 94, 95 ashbeds, 61, 62, 78, 95 T mechanical soil disturbance, 62 slash burning, 61, 73 Tarnagulla, 35 seedling. See regeneration:seedling termites, 29, 35, 36 selective cutting, 3 thinning, 13, 14, 18, 19, 20, 38, 39, 63, 64, Sheen, William, 45 68, 70, 71, 72, 73, 74, 80, 83, 84, 85, 86, Silver‐leaved Ironbark. See E. melanophloia 87, 88, 90, 91, 115, 116, 120, 127 silvicultural research, 18 commercial, v, vi, 9, 10, 17, 20, 29, 43, silvicultural systems, 2, 62, 67, 68, 69, 70, 57, 58, 61, 65, 68, 69, 76, 79, 83, 84, 71, 72, 73, 74 86, 115 clear‐felling, 68, 72 damage, 36, 85, 123 Coppice with standards, 68 ecological, iii, 20, 29, 43, 53, 68, 69, 71, effectiveness of alternatives, 69 88, 89, 90 Group selection growth response to, 63 salvage coupe, 78 impacts on fauna, iii, 70, 72 seedling‐promotion coupe, 78 pre‐commercial, 86, 115, 127 marking and harvesting, 75, 78, 81, 83 timber industry, 12, 14 Single Tree Selection, 69, 74, 75, 79, 82, charcoal, 14, 15 85, 115, 116 durable timbers, 12, 17 Thinning from below, 83 environmental impact, 67, 70 Silviculture Decision Support System, 69, flooring, 17 72, 74, 114 furniture, 17 site quality, 51, 75, 80, 81 harvesting, 73, 78, 85, 115, 125, 128 soils, 3, 22, 30, 31, 32, 35, 41, 51, 60, 65, 66, poles, 12, 13, 14, 80 74, 93 sawn timber, 17, 128 bleached duplex, 30 sleepers, 12, 14 red duplex, 30 sustainable harvest levels, 17 skeletal, 22, 32, 65 Timber Industry Action Plan, 67 sowing, 40, 55, 57, 58, 60, 61, 79, 92, 93, timber production. See timber industry 94, 95, 96, 128, 129 timber products. See timber industry sowing rates, 93 Trust for Nature, 88 Special Management Zone, 114, 125 Special Protection Zone, 125 St Arnaud, 4, 6, 7, 8, 32, 41, 50 U standards. See Coppice with standards State forest, iii, 5, 10, 11, 15, 17, 67, 70, 75, utilisation, v, 7, 13, 67, 68 81, 92, 93, 94, 95, 120, 130 Stawell, 1, 4 stocking, 6, 40, 42, 60, 74, 75, 77, 78, 81, 82, 93, 94, 116

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V wind‐throw, 33 Wombat State Forest, 65 Victorian School of Forestry and Land woodlands, 3, 4, 7, 9, 10, 11, 12, 24, 25, 30, Management, 19 63, 93 working circles, 6, 7 W X Wallabia bicolor, 36, 62 Warby Ranges, 4 Xanthorrhoea australis, 33 water production Wungong catchment, 71 Y Wellsford, 13, 14, 15, 38 Werribee Gorge, 4 Yellow Box. See E. melliodora White Box. See E. albens Yellow Gum. See E.leucoxylon White Ironbark. See E.leucoxylon