Study of Old-Growth Forest in Victoria's North East
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Study of Old-growth Forest in Victoria’s North East Department of Natural Resources and Environment Victoria Forests Service Technical Reports 98-1 June 1998 Copyright © Department of Natural Resources and Environment 1998 Published by the Department of Natural Resources and Environment PO Box 500, East Melbourne Victoria 3002, Australia http://www.nre.vic.gov.au This publication is copyright. Apart from any fair dealing for private study, research, criticism or review as permitted under the Copyright Act 1968, no part of this publication may be reproduced, stored in a retrieval system or transmitted in any form or by any means, electronic, photocopying or otherwise, without prior permission of the copyright owner. The National Library of Australia Cataloguing-in- Publication entry: Study of Old-growth Forest in Victoria’s North East. Bibliography. ISSN 1443-1106 ISBN 0 7311 4440 6 1.Forest Management - Victoria, Northeastern. 2.Forests and forestry - Victoria, Northeastern. 3.Old-growth forests - Victoria, Northeastern. I. Victoria. Dept. of Natural Resources and Environment. (Series: Forests Service Technical Report ; 98 -1). 634.909945 General 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. Cover design and layout: Wamen Press Cover photographs: 1. Montane/ Sub-alpine Woodland near Mt Howitt - Geoff Lucas, 2. Alpine Complex - from Tims Spur, - Geoff Lucas Printing by Wamen Press i FOREWORD During the early 1990’s the then Department of Conservation and Natural Resources (CNR) and the Australian Heritage Commission (AHC) reached joint agreement on a series of studies to evaluate National Estate values in Victoria’s North East. One of the studies undertaken involved an investigation of the area’s old-growth forests. The work was carried out by a team of specialists, and overseen by a Steering Committee that had been established as part of the joint CNR/AHC National Estate process. This report provides a brief background to the study, outlines the methodology used, summarises the results, and briefly discusses the future management of the area’s old-growth forests. The study has proved to be an essential input into the development of a Forest Management Plan for the area, and more recently, in the work that is under way to prepare a Regional Forest Agreement for the area. Richard Rawson Executive Director Forests Service. ii SUMMARY The objective of this study was to determine the extent and distribution of old-growth forest in North East Victoria. The study area included the 1.25 million hectares of forested public land within the North East Regional Forest Agreement area. Old-growth forest was originally defined in the East Gippsland Old-growth Forest Study as: forest which contains significant amounts of its oldest growth stage in the upper stratum - usually senescing trees - and has been subjected to any disturbance, the effect of which is now negligible (Woodgate et al. 1994). The analysis methods developed for previous old-growth forest surveys in East Gippsland and Central Highlands were applied in this North East study. Three key elements: forest growth stage, Ecological Vegetation Class (EVC) and disturbance history; were mapped for all forested public land. A limited number of old-growth forest stands identified in the analysis were field checked and ongoing field verification is recommended to be incorporated into routine forest management activities. The study estimated that 260,000 hectares or 21% of forested public land in the North East is old- growth forest. Old-growth forest was identified in 13 EVCs and one vegetation mosaic found within the study area. Generally, the larger portions of old-growth forest were found in the foothill and montane forests, with the EVCs on the drier sites tending to exhibit higher proportions of old- growth. Old-growth forest tended to be rare in the lowland forest types (generally favoured for agriculture) and disturbance tended to be more pronounced on flatter areas. iii CONTENTS FOREWORD ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ii SUMMARY ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... iii 1. INTRODUCTION ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... 1 1.1 BACKGROUND ... ... ... ... ... ... ... ... ... ... ... ... ... ... 1 1.2 STUDY OBJECTIVES ... ... ... ... ... ... ... ... ... ... ... ... ... 1 1.3 STUDY AREA ... ... ... ... ... ... ... ... ... ... ... ... ... ... 2 2. CONCEPTS AND DEFINITIONS OF OLD-GROWTH FOREST ... ... ... ... ... ... ... 3 3. SURVEY OF OLD-GROWTH ATTRIBUTES ... ... ... ... ... ... ... ... ... ... 4 3.1 INTRODUCTION ... ... ... ... ... ... ... ... ... ... ... ... ... ... 4 3.2 SURVEY ATTRIBUTES ... ... ... ... ... ... ... ... ... ... ... ... ... 4 3.2.1 Forest ... ... ... ... ... ... ... ... ... ... ... ... ... ... 4 3.2.2 Forest growth stage ... ... ... ... ... ... ... ... ... ... ... 4 3.2.3 Forest type ... ... ... ... ... ... ... ... ... ... ... ... ... 4 3.2.4 Ecological vegetation classes (EVCs) ... ... ... ... ... ... .. ... 5 3.2.5 Disturbance influences ... ... ... ... ... ... ... ... ... ... 5 4. FOREST GROWTH STAGES ... ... ... ... ... ... ... ... ... ... ... ... ... 6 4.1 CONCEPTS ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... 6 4.1.1 Eucalypt crown cover ... ... ... ... ... ... ... ... ... ... ... 6 4.1.2 Eucalypt crown form ... ... ... ... ... ... ... ... ... ... ... 6 4.1.3 Forest growth stage ... ... ... ... ... ... ... ... ... ... ... 8 4.2 SURVEY METHODS ... ... ... ... ... ... ... ... ... ... ... ... ... 9 4.2.1 Crown form mapping ... ... ... ... ... ... ... ... ... ... ... 9 4.2.2 Aerial photograph mapping types ... .. ... ... ... ... ... ... ... 9 4.2.3 Transfer of line work ... ... ... ... ... ... ... ... ... ... ... 9 4.2.4 Forest growth stage mapping ... ... ... ... ... ... ... ... ... 10 4.3 RESULTS ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... 10 5. ECOLOGICAL VEGETATION CLASSES ... ... ... ... ... ... ... ... ... ... ... 11 5.1 INTRODUCTION ... ... ... ... ... ... ... ... ... ... ... ... ... ... 11 5.2 CONCEPTS ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... 11 5.2.1 Ecological vegetation class (EVC)... ... ... ... .. ... ... ... ... 11 5.2.2 Floristic community and sub-community ... ... ... ... ... ... ... 11 5.3 METHODS ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... 11 5.3.1 Vegetation survey and description of floristic communities ... ... .. ... 11 5.3.2 Mapping of ecological vegetation classes ... ... ... ... ... ... ... 12 5.3.3 Data transfer ... ... ... ... ... ... ... ... ... ... ... ... 12 5.3.4 Limitations and qualifications ... ... ... ... ... ... ... ... ... 12 5.4 RESULTS ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... 13 5.4.1 Plains ... ... ... ... ... ... ... ... ... ... ... ... ... ... 13 5.4.2 Valleys... ... ... ... .. ... ... ... ... ... ... ... ... ... 13 5.4.3 Low hills ... ... ... ... ... ... ... ... ... ... ... ... ... 13 5.4.4 Foothills ... ... ... ... ... ... ... ... ... ... ... ... ... 13 5.4.5 Montane ... ... ... ... ... ... ... ... ... ... ... ... ... 13 5.4.6 Sub-alpine ... ... ... ... ... ... ... ... ... ... ... ... ... 13 5.4.7 Poorly sampled vegetation ... ... ... ... ... ... ... ... ... ... 14 iv 6. FOREST DISTURBANCE ... ... ... ... ... ... ... ... ... ... ... ... ... 17 6.1 INTRODUCTION ... ... ... ... ... ... ... ... ... ... ... ... ... ... 17 6.2 GRAZING ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... 17 6.3 MINING ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... 18 6.4 AGICULTURAL CLEARING ... ... ... ... ... ... ... ... ... ... ... ... 18 6.5 TIMBER HARVESTING ... ... ... ... ... ... ... ... ... ... ... ... ... 19 6.6 WILDFIRE ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... 20 6.7 FUEL REDUCTION BURNS ... ... ... ... ... ... ... ... ... ... ... ... 20 6.8 RESULTS ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... 20 7. AGE OF FORESTS IN NORTH EAST VICTORIA ... ... ... ... ... ... ... ... ... 22 8. ANALYSIS OF OLD-GROWTH STATUS ... ... ... ... ... ... ... ... ... ... ... 23 8.1 INTRODUCTION ... ... ... ... ... ... ... ... ... ... ... ... ... 23 8.2 METHOD ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... 23 8.2.1 Resource data input and validation ... ... ... ... ... ... ... ... 25 8.2.2 Disturbance data input and validation ... ... ... ... ... .. ... ... 26 8.2.3 Evaluation of candidate old-growth areas ... ... ... ... ... ... ... 29 8.2.4 Forest Categories ... ... ... ... ... ... ... ... ... ... ... 30 8.3 RESULTS ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... 32 8.3.1 Maps and Area Statements ... ... ... ... ... ... ... ... .. ... 32 8.4 ADVANCES AND LIMITATIONS IN ANALYSIS ... ... ... ... ... ... ... ... ... 35 8.4.1 Advances ... ... ... ... ... ... ... ... ... ... ... ... ... 35 8.4.2 Limitations ... ... ... ... ... ... ... ... ... ... ... ... ... 35 9. CONCLUSIONS ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... 36 10. MANAGEMENT OF OLD-GROWTH FOREST ... ... ... ... ... ... ... ... ... ... 37 10.1 INTRODUCTION ... ... ... ... ... ... ... ... ... ... ... ... ... ... 37 10.2 LAND-USE PLANNING - LAND CONSERVATION COUNCIL ... ... ... ... ... ... 37 10.3 FOREST MANAGEMENT