Basal Area — Benchmark Detail

Benchmark Value

40 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.

Evidence & Context

A basal area exceeding 35−40 m²/ha within a shelterbelt is likely to be detrimental.

Metric Definition:

Basal area above which competition causes economic detriment to cropping productivity.

Benchmark Definition:

Economic tipping point for basal area in cropping systems.

Justification:

Based on evidence of significant crop yield suppression due to competition.

Sources (1)

Shelterbelt species composition and age determine structure: Consequences for ecosystem services

Shelterbelt species composition and age determine structure: Consequences for ecosystem services

View Source

Supporting Sources (2)

Additional references from the underlying research that informed this benchmark.

A guide to managing Box Gum Grassy Woodlands - DCCEEW, accessed August 4, 2025

Contextual Support Journal

White Box - Yellow Box - Blakely's Red Gum Grassy Woodlands and Derived Native Grasslands National Ecological Community: A Guide to Managing Box-Gum Grassy Woodlands. Department of Climate Change, Energy, the Environment and Water, Australian Government (2012).

View Source

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

Context

Region Australia
Biome Temperate Grassy Woodlands & Plains
Land Use Agricultural Crop Production
Assessment Not Stated
Evidence Type DegradationThreshold

Lifecycle

Status Active
Version 1
Effective From 7 Jun 2026

Notes

Exceeding this basal area likely causes economic detriment due to competition for water and light. AssessmentContext defaulted to 'Not Stated' because the source document did not state one.

Related Benchmarks

Other benchmarks in the AUS-TGP-AGR-BAS family.