Soil Structure & Compaction

AUS-TSW-FOR-SSC General Moderate confidence

Benchmark Value

3000 kPa

Direction: Lower 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

There is broad consensus that a penetration resistance of approximately 3 MPa, or 3,000 kPa, represents an effective upper limit for the growth of most plant roots.

Metric Definition:

Penetration resistance threshold above which root elongation largely ceases.

Benchmark Definition:

Critical upper limit of soil penetration resistance beyond which root growth is severely restricted in temperate semi-arid shrublands and open woodlands under production forestry.

Justification:

Scientific consensus from multiple studies indicating root elongation ceases at this level, though confidence is moderated due to source types and biome proxy.

Sources (2)

Healthy Roots and Healthy Trees - 2.926 - CSU Extension - Colorado State University

Healthy Roots and Healthy Trees - 2.926 - CSU Extension - Colorado State University

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Tree Root Growth Requirements - Arborcare Tree and Garden ... Journal

Tree Root Growth Requirements - Arborcare Tree and Garden ...

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Supporting Sources (5)

Additional references from the underlying research that informed this benchmark.

Preview of (PDF) Review of factors affecting disturbance, compaction and trafficability of soils with particular reference to timber harvesting in the forests of south-west Western Australia - ResearchGate, accessed July 30, 2025,

(PDF) Review of factors affecting disturbance, compaction and trafficability of soils with particular reference to timber harvesting in the forests of south-west Western Australia - ResearchGate, accessed July 30, 2025,

Contextual Support

Australia's State of the Forests Report Synthesis 2023

View Source

Impacts of Logging-Associated Compaction on Forest Soils: A Meta-Analysis - Frontiers, accessed July 11, 2025,

Contextual Support Journal

Impacts of Logging-Associated Compaction on Forest Soils: A Meta-Analysis - Frontiers, accessed July 19, 2025

View Source

National Soil Monitoring Program - CSIRO, accessed August 4, 2025,

Contextual Support GreyLiterature

National Soil Monitoring Program - CSIRO, accessed July 8, 2025

View Source

Soil Compaction and Productivity Evolution in a Harvested and Grazed Mediterranean Scots Pine (Pinus sylvestris L.) Forest

Contextual Support Journal

Soil Compaction and Productivity Evolution in a Harvested and Grazed Mediterranean Scots Pine (Pinus sylvestris L.) Forest

View Source

Soil Compaction and Productivity Evolution in a Harvested and Grazed Mediterranean Scots Pine (Pinus sylvestris L.) Forest - Universitat Politècnica de Madrid - Portal Científico UPM, accessed July 11, 2025,

Contextual Support Journal

View Source

Context

Region Australia
Biome Temperate Semi-Arid Shrublands & Open Woodlands
Land Use Production Forestry
Assessment Not Stated
Evidence Type DegradationThreshold

Lifecycle

Status Active
Version 1
Effective From 7 Jun 2026

Notes

This threshold marks the boundary between constrained and severely restrictive soil conditions for root growth. AssessmentContext defaulted to 'Not Stated' because the source document did not state one.

Related Benchmarks

Other benchmarks in the AUS-TSW-FOR-SSC family.