Basal Area

AUS-TDG-LVG-BAS General Moderate confidence

Benchmark Value

20 m²/ha
Direction: Higher is desirable ↑
Form: MaximumOnly

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 18 benchmarks together — the OptimalRange form drives the primary score, while 17 guard(s) constrain the result.

Evidence & Context

An upper boundary around >20-25 m²/ha, beyond which detrimental impacts on pasture productivity and potential ecological imbalances become significant in a grazing context.

Metric Definition:

Basal Area (BA) quantifies the cross-sectional area of tree stems at breast height per unit ground area.

Benchmark Definition:

This benchmark defines the upper basal area threshold above which negative ecological and pasture productivity impacts occur in temperate dry woodlands and native grasslands under livestock grazing.

Justification:

Based on evidence of competition with pasture, altered ecosystem structure, water stress, and stand stagnation at high basal area levels.

Sources (1)

Preview of Synthesis derived from multiple sources including Lindenmayer et al. (2020), Wardle et al. (2024), Florence (2002), Fensham (1998), NSW OEH (2019), Keto & Scott (2024). See report Sections 3 & 6 for details.
Synthesis derived from multiple sources including Lindenmayer et al. (2020), Wardle et al. (2024), Florence (2002), Fensham (1998), NSW OEH (2019), Keto & Scott (2024). See report Sections 3 & 6 for details. Journal

Synthesis derived from multiple sources including Lindenmayer et al. (2020), Wardle et al. (2024), Florence (2002), Fensham (1998), NSW OEH (2019), Keto & Scott (2024). See report Sections 3 & 6 for details.

View Source

Context

  • Region Australia
  • Biome Temperate Dry Woodlands & Native Grasslands
  • Land Use Livestock Grazing & Pasture
  • Assessment Not Stated
  • Evidence Type DegradationThreshold

Lifecycle

  • Status Active
  • Version 1
  • Effective From 8 Jun 2026

Notes

Reduced pasture production; potential understorey diversity loss; 'unnatural' thickening. AssessmentContext defaulted to 'Not Stated' because the source document did not state one.