Basal Area

AUS-TDG-FOR-BAS General Moderate confidence

Benchmark Value

No specific value — see range
Range: 10 to 18 m²/ha
Optimal Range: 10 to 18
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 7 benchmarks together — the OptimalRange form drives the primary score, while 6 guard(s) constrain the result.

Contributing Benchmarks

OptimalRange Primary OptimalRange Guard Point Guard OptimalRange Guard OptimalRange Guard MinimumOnly Guard MaximumOnly Guard

Evidence & Context

a reference range of 10–18 m²/ha is proposed.

Metric Definition:

Basal area is defined as the sum of the cross-sectional areas of all tree stems in a stand, measured at breast height (typically 1.3 m above ground), and expressed per unit of land area (e.g., m²/ha).

Benchmark Definition:

This benchmark defines the reference basal area range representing the best available condition for production forestry that supports high ecological health in Australian Temperate Dry Woodlands & Native Grasslands.

Justification:

This range encompasses the upper end of the WA Jarrah ecological thinning targets for low-rainfall zones (9-15 m²/ha) and sits below the immediate self-thinning thresholds of key dry woodland species (approx. 16.8-19.0 m²/ha).

Sources (1)

Preview of A report on silvicultural guidelines for the 2024- 2033 Forest Management Plan to the Western Australian Department of Biodiversity, Conservation and, accessed July 12, 2025,
A report on silvicultural guidelines for the 2024- 2033 Forest Management Plan to the Western Australian Department of Biodiversity, Conservation and, accessed July 12, 2025, Journal

Ecological Thinning Information and Workbook - AWS

View Source

Supporting Sources (8)

Additional references from the underlying research that informed this benchmark.

Preview of Approved Conservation Advice for the White Box - Yellow Box - Blakely's Red Gum Grassy Woodland and Derived Native Grassland - DCCEEW, accessed August 12, 2025,
Approved Conservation Advice for the White Box - Yellow Box - Blakely's Red Gum Grassy Woodland and Derived Native Grassland - DCCEEW, accessed August 12, 2025,
Contextual Support Journal

Conservation Advice for Lowland Grassy Woodland in the South East Corner Bioregion

View Source
Preview of Australia's forests – overview - DAFF, accessed May 15, 2025
Australia's forests – overview - DAFF, accessed May 15, 2025
Contextual Support Journal

Australia's forests – overview - DAFF, accessed May 15, 2025

View Source
Preview of Full article: Active management: a definition and considerations for implementation in forests of temperate Australia - Taylor & Francis Online
Full article: Active management: a definition and considerations for implementation in forests of temperate Australia - Taylor & Francis Online
Contextual Support Methodology Source Journal

Full article: Active management: a definition and considerations for implementation in forests of temperate Australia - Taylor & Francis Online, accessed May 15, 2025

View Source
Preview of Function Attribute Benchmarks for the Biodiversity Assessment Method: Data audit, compilation and analysis - Environment and Heritage, accessed July 10, 2025,
Function Attribute Benchmarks for the Biodiversity Assessment Method: Data audit, compilation and analysis - Environment and Heritage, accessed July 10, 2025,
Contextual Support

Victorian State of the Environment report

View Source
Preview of Hester, A. J., Pakeman, R. J., Harrison, S., & Ross, L. C. (2017). Thresholds of biodiversity and ecosystem function in a forest ecosystem undergoing dieback. Scientific Reports, 7, 6775.
Hester, A. J., Pakeman, R. J., Harrison, S., & Ross, L. C. (2017). Thresholds of biodiversity and ecosystem function in a forest ecosystem undergoing dieback. Scientific Reports, 7, 6775.
Contextual Support Direct Evidence Journal

Pinpointing Ecological Thresholds to Enhance Ecosystem Management

View Source
Preview of Native Forests Show Resilience to Selective Timber Harvesting in Southeast Queensland, Australia - Frontiers
Native Forests Show Resilience to Selective Timber Harvesting in Southeast Queensland, Australia - Frontiers
Contextual Support Direct Evidence Journal

Native Forests Show Resilience to Selective Timber Harvesting in Southeast Queensland, Australia - Frontiers, accessed May 15, 2025

View Source
Preview of Restoration of temperate savannas and woodlands - Forest Service, accessed August 6, 2025,
Restoration of temperate savannas and woodlands - Forest Service, accessed August 6, 2025,
Contextual Support Methodology Source

Function Attribute Benchmarks for the Biodiversity Assessment ..., accessed May 15, 2025

View Source
Preview of Thresholds of biodiversity and ecosystem function in a forest ...
Thresholds of biodiversity and ecosystem function in a forest ...
Contextual Support Journal

Thresholds of biodiversity and ecosystem function in a forest ...

View Source

Context

  • Region Australia
  • Biome Temperate Dry Woodlands & Native Grasslands
  • Land Use Production Forestry
  • Assessment Conservation Target
  • Evidence Type TargetCondition

Lifecycle

  • Status Active
  • Version 1
  • Effective From 26 May 2026

Notes

Represents a managed condition likely to support a relatively open canopy structure, conducive to the health and diversity of the native understorey.