Basal Area — Benchmark Detail - Nature Index

Benchmark Value

No specific value — see range

Range: 9 to 14 m²/ha

Thresholds: Lower: 9, Upper: 14

Optimal Range: 9 to 14

Direction: Higher is desirable ↑

Form: OptimalRange

Scoring Curve

This curve shows how a field measurement for this indicator would score across all available benchmark forms in this context. The scoring engine uses 2 benchmarks together — the OptimalRange form drives the primary score, while 1 guard(s) constrain the result.

Contributing Benchmarks

OptimalRange Primary MinimumOnly Guard

Evidence & Context

"Trees with good crowns are retained at 9–14 m2 of basal area per hectare."

Metric Definition:

Cross-sectional area of trees at 1.3m

Benchmark Definition:

This benchmark represents the optimal range of basal area per hectare for trees with good crowns in the Alpine and Subalpine Complex biome under production forestry, indicating the cross-sectional area of tree stems at 1.3 meters above ground.

Justification:

Provides seed and microclimate protection (1.4C) while minimizing moisture competition.

Sources (1)

Preview of Thinning Regrowth Eucalypts - Sustainable Timber Tasmania, accessed March 28, 2026,

Thinning Regrowth Eucalypts - Sustainable Timber Tasmania, accessed March 28, 2026, GreyLiterature

Silvicultural systems for native eucalypt forests - Sustainable Timber Tasmania

Supporting Sources (23)

Additional references from the underlying research that informed this benchmark.

Preview of Buckley, T. N., Turnbull, T. L., Pfautsch, S., Gharun, M., & Adams, M. A. (2012). Differences in water use between mature and regrowth Alpine Ash (Eucalyptus delegatensis R. Baker) in high elevation catchments.

Buckley, T. N., Turnbull, T. L., Pfautsch, S., Gharun, M., & Adams, M. A. (2012). Differences in water use between mature and regrowth Alpine Ash (Eucalyptus delegatensis R. Baker) in high elevation catchments.

Direct Evidence Journal

Buckley, T. N., Turnbull, T. L., Pfautsch, S., Gharun, M., & Adams, M. A. (2012). Differences in water use between mature and regrowth Alpine Ash (Eucalyptus delegatensis R. Baker) in high elevation catchments.

Preview of Continuous Cover Forestry in practice - ASKAFOR, accessed March 28, 2026,

Continuous Cover Forestry in practice - ASKAFOR, accessed March 28, 2026,

Contextual Support Journal

Continuous Cover Forestry in practice - ASKAFOR

Preview of EARLY GROWTH OF EUCALYPTUS DELEGATENSIS PROVENANCES IN FOUR FIELD TRIALS IN SOUTH-EASTERN AUSTRALIA, accessed March 28, 2026,

EARLY GROWTH OF EUCALYPTUS DELEGATENSIS PROVENANCES IN FOUR FIELD TRIALS IN SOUTH-EASTERN AUSTRALIA, accessed March 28, 2026,

Contextual Support Government

EARLY GROWTH OF EUCALYPTUS DELEGATENSIS PROVENANCES IN FOUR FIELD TRIALS IN SOUTH-EASTERN AUSTRALIA

Preview of Forest Ecology and Management - Northwest Fire Science Consortium, accessed March 28, 2026,

Forest Ecology and Management - Northwest Fire Science Consortium, accessed March 28, 2026,

Contextual Support Journal

Forest Ecology and Management - Northwest Fire Science Consortium

Preview of Forest Practices Authority (FPA) Tasmania. (2021). Technical Bulletin 2: Eucalyptus delegatensis forests.

Forest Practices Authority (FPA) Tasmania. (2021). Technical Bulletin 2: Eucalyptus delegatensis forests.

Direct Evidence Journal

Environmental Protection Authority (EPA) NSW. (2010). Silvicultural guidelines for the Code of Practice for Private Native Forestry.

Preview of Forestry Industry Action Plan, accessed March 28, 2026,

Forestry Industry Action Plan, accessed March 28, 2026,

Contextual Support Journal

Impact of intense disturbance on the structure and composition of wet-eucalypt forests: A case study from the Tasmanian 2016 wildfires | PLOS One, accessed April 6, 2026

Preview of Full article: Active management: a definition and considerations for implementation in forests of temperate Australia - Taylor & Francis, accessed March 28, 2026,

Full article: Active management: a definition and considerations for implementation in forests of temperate Australia - Taylor & Francis, accessed March 28, 2026,

Contextual Support

Full article: Active management: a definition and considerations for implementation in forests of temperate Australia - Taylor & Francis

Preview of guidelines for sustainable forestry on private lands in nsw - ResearchGate, accessed August 1, 2025,

guidelines for sustainable forestry on private lands in nsw - ResearchGate, accessed August 1, 2025,

Contextual Support

Smith, A. (2019). Guidelines for Sustainable Forestry on Private Lands in NSW.

Preview of INTRODUCTION - DBCA Library, accessed March 28, 2026,

INTRODUCTION - DBCA Library, accessed March 28, 2026,

Contextual Support Journal

INTRODUCTION - DBCA Library

Preview of Long-Term Empirical Studies Highlight Multiple Drivers of Temporal Change in Bird Fauna in the Wet Forests of Victoria

Long-Term Empirical Studies Highlight Multiple Drivers of Temporal Change in Bird Fauna in the Wet Forests of Victoria

Contextual Support Journal

Zhou, X., et al. (2025). Forest cover and canopy health mapping in Australian subalpine landscape: supervised machine learning models for Sentinel-2 and Landsat images.

Preview of Macroecology of Australian Tall Eucalypt Forests: Baseline Data from a Continental-Scale Permanent Plot Network - PMC

Macroecology of Australian Tall Eucalypt Forests: Baseline Data from a Continental-Scale Permanent Plot Network - PMC

Direct Evidence Journal

Macroecology of Australian Tall Eucalypt Forests: Baseline Data from a Continental-Scale Permanent Plot Network - PMC

Preview of Macroecology of Australian Tall Eucalypt Forests: Baseline Data from a Continental-Scale Permanent Plot Network - PMC, accessed March 28, 2026,

Macroecology of Australian Tall Eucalypt Forests: Baseline Data from a Continental-Scale Permanent Plot Network - PMC, accessed March 28, 2026,

Contextual Support Journal

Unraveling Elevation-Driven Variations in Forest Structure and Composition in Western Nepal - MDPI

Preview of Modelling individual tree maximum basal area growth rates of five tall eucalypt species growing in even-aged forests - ResearchGate, accessed March 28, 2026,

Modelling individual tree maximum basal area growth rates of five tall eucalypt species growing in even-aged forests - ResearchGate, accessed March 28, 2026,

Contextual Support Journal

Tasmania's giant eucalypts: discovery, documentation, macroecology and conservation status of the world's largest - Amazon S3

Preview of NSW Environment Protection Authority. (n.d.). Techniques for Measuring Stand Basal Area. Private Native Forestry Code of Practice Guideline No. 5.

NSW Environment Protection Authority. (n.d.). Techniques for Measuring Stand Basal Area. Private Native Forestry Code of Practice Guideline No. 5.

Contextual Support Journal

Techniques for Measuring Stand Basal Area - NSW Environment Protection Authority

Preview of Private Forests Tasmania. (2023). Native forest silvicultural systems: Fact Sheet 3.

Private Forests Tasmania. (2023). Native forest silvicultural systems: Fact Sheet 3.

Direct Evidence Journal

Private Forests Tasmania. (2023). Native forest silvicultural systems: Fact Sheet 3.

Preview of Private Native Forestry Code of Practice for Southern NSW - FAOLEX, accessed May 15, 2025

Private Native Forestry Code of Practice for Southern NSW - FAOLEX, accessed May 15, 2025

Contextual Support Regulatory Framework Journal

Natural Resources Commission (NRC) NSW. (2022). Final report: Private Native Forestry Review.

Preview of Private Native Forestry Code of Practice for Southern NSW - Local Land Services, accessed May 26, 2025

Private Native Forestry Code of Practice for Southern NSW - Local Land Services, accessed May 26, 2025

Contextual Support Journal

Development of a RIS for variations to the Code of Practice for Timber Production 2014 - Victorian Government

Preview of Research program - Koala response to harvesting in NSW north coast state forests Final report (updated) December 2022 - Natural Resources Commission, accessed March 28, 2026,

Research program - Koala response to harvesting in NSW north coast state forests Final report (updated) December 2022 - Natural Resources Commission, accessed March 28, 2026,

Contextual Support Journal

Research program - Koala response to harvesting in NSW north coast state forests Final report (updated) December 2022 - Natural Resources Commission

Preview of Schedule-1-Management-Standards-and-Procedures-for-timber-harvesting-operations-in-Victorias-State-forests.pdf, accessed March 28, 2026,

Schedule-1-Management-Standards-and-Procedures-for-timber-harvesting-operations-in-Victorias-State-forests.pdf, accessed March 28, 2026,

Contextual Support Journal

Forestry Corporation of NSW. (2022). NSW Forestry Snapshot Report 2021–22.

Preview of Silvicultural monitoring in uneven-aged highland dry Eucalyptus delegatensis forests in Tasmania, accessed March 28, 2026,

Silvicultural monitoring in uneven-aged highland dry Eucalyptus delegatensis forests in Tasmania, accessed March 28, 2026,

Contextual Support Journal

Silvicultural monitoring in uneven-aged highland dry Eucalyptus delegatensis forests in Tasmania

Preview of Technical Bulletin 2: Eucalyptus delegatensis forests

Technical Bulletin 2: Eucalyptus delegatensis forests

Regulatory Framework Journal

Forestry Tasmania. (2001). Eucalyptus delegatensis Forests. Technical Bulletin No. 2.

Preview of Thinning Regrowth Eucalypts - Sustainable Timber Tasmania

Thinning Regrowth Eucalypts - Sustainable Timber Tasmania

Direct Evidence Journal

Thinning Regrowth Eucalypts - Sustainable Timber Tasmania

Preview of Victoria Department of Environment, Land, Water and Planning (DELWP). (2022). TSCRA Tranche 1 Permanent Protections Report.

Victoria Department of Environment, Land, Water and Planning (DELWP). (2022). TSCRA Tranche 1 Permanent Protections Report.

Regulatory Framework Journal

Victoria Department of Environment, Land, Water and Planning (DELWP). (2022). TSCRA Tranche 1 Permanent Protections Report.