Soil pH — Benchmark Detail

Benchmark Value

No specific value — see range

Range: 5.5 to 6.5 pH

Optimal Range: 5.5 to 6.5

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

Optimal Soil pH (1:5 soil:water) Range: pH 5.5 – 6.5.

Metric Definition:

Soil pH measured as a 1:5 soil:water suspension.

Benchmark Definition:

This benchmark defines the optimal soil pH range of 5.5 to 6.5 for production forestry in the Alpine and Subalpine Complex biome, promoting vigorous growth, nutrient availability, and healthy microbial activity.

Justification:

Conducive to vigorous growth of species like Eucalyptus delegatensis; good nutrient availability; minimized Al/Mn toxicity; healthy microbial activity.

Sources (1)

Preview of (PDF) The pH of Australian soils: field results from a national survey - ResearchGate, accessed July 25, 2025,

(PDF) The pH of Australian soils: field results from a national survey - ResearchGate, accessed July 25, 2025, Journal

Caritat, P. de, & Cooper, M. (2011). The pH of Australian soils: Field results from a national survey. Soil Research, 49, 172-182.

View Source

Context

Region Australia
Biome Alpine and Subalpine Complex
Land Use Production Forestry
Assessment Production Forestry
Vegetation Forest
Evidence Type HealthyOperationalRange

Lifecycle

Status Active
Version 2
Effective From 9 Jun 2026

Notes

Upper end (6.5) acknowledges natural ecosystem constraints.

Related Benchmarks

Other benchmarks in the AUS-ASC-FOR-SPH family.