Rangeland condition rating system

Page last updated: Wednesday, 27 May 2020 - 9:18am

Officers of the Department of Primary Industries and Regional Development (DPIRD) assess rangeland condition to provide advice on planning and managing grazing pressure on leases, and for requirements of the Soil and Land Conservation Act 1945 and the Land Administration Act 1997. Lessees and managers can use the same assessment method to track changes in livestock carrying capacity and resource condition, and improve sustainable rangeland resource use.

Rangeland condition is a function of soil erosion and pasture condition

DPIRD's rangelands officers use the matrix of soil erosion extent and pasture condition ratings to arrive at the rangeland condition score (good, fair or poor) for each monitoring site or lease inspection point during assessments. Lessees and managers are informed of when rangelands officers will be visiting their lease and they are invited to accompany officers during assessments.

The matrix for rangeland condition

Table 1 Matrix for determining rangeland (resource) condition based on combining scores for extent of soil erosion and pasture condition (adapted from Payne et al. 1998)
Rangeland condition matrix

Pasture condition rating
1 or 2

Pasture condition rating
3

Pasture condition rating
4 or 5

Soil erosion rating
0
Good Fair Poor
Soil erosion rating
1 or 2
Good Fair Poor
Soil erosion rating
3
Fair Poor Poor
Soil erosion rating
4 or 5
Poor Poor Poor

Pasture condition ratings

Table 2 Pasture condition rating (adapted from Payne et al. 1979)
# Rating Description
1 Excellent or very good for the land unit/vegetation type, the compositions and cover of shrubs, perennial herbs and grasses is near optimal; free of obvious reductions in palatable species or increases in unpalatable species, or the habitat type supports vegetation which is predominately unattractive to herbivores and is thus largely unaltered by grazing.
2 Good Perennials present include all or most of the palatable species expected; some less palatable or unpalatable species may have increased, but the total perennial cover is not very different from optimal.
3 Fair Moderate losses of palatable perennials and/or increases in unpalatable shrubs or grasses, but most palatable species and stability desirables still present; foliar cover is less than on comparable sites rated 1 or 2 unless unpalatable species have increased.
4 Poor Conspicuous losses of palatable perennials; foliar cover is either decreased through general loss of perennials or is increased by the invasion of unpalatable species.
5 Very poor Few palatable perennials remain; cover is either greatly reduced, with much bare ground arising from loss of stability desirables, or has become dominated by a proliferation of unpalatable species.

Soil erosion ratings

Table 3 Soil erosion rating
Rating Severity Percentage of assessment area affected
0 No accelerated erosion present 0%
1 Slight erosion <10%
2 Minor erosion 10–25%
3 Moderate erosion 25–50%
4 Severe erosion 50–75%
5 Extreme erosion 75–100%

Soil surface condition categories

Rangeland condition is also indicated by soil surface characteristics, as part of landscape functional analysis. Soil surface condition describes the soil’s capacity to retain water, and to remain stable and productive under variable conditions (Table 4). Note: these condition categories are recommended in the pastoralist managed site assessments – Grassland sites.

Table 4 Soil surface condition categories and description
Condition Description
Very good stable soil surface (no topsoil loss occurring); many physical barriers, including decomposing litter, live plants and fallen timber, to retard water flows and promote infiltration
Good soil surface is mostly stable (no or little topsoil loss occurring); some accumulated litter and live plants; minor evidence of loss of water or litter from site
Fair some signs of topsoil loss; some litter, but with little evidence of decomposition; reduced obstructions to intercept water flows, including few live plants
Poor significant topsoil loss; minimal litter present; few obstructions to intercept water flows
Very poor almost total loss of topsoil; exposed soil surfaces are impermeable; very few objects to intercept water flows; no accumulated litter; no live plants.

Management options

DPIRD's rangelands officers provide advice on management options for maintaining or improving rangeland condition and can help organise group training workshops on sustainable rangeland management and remediation/rehabilitation techniques where resources are available.

References

Payne, AL, Kubicki, A, Wilcox, DG & Short, LC 1979, 'A report on erosion and range condition in the west Kimberley area of Western Australia', Technical bulletin 42, Western Australian Department of Agriculture, viewed 21 November 2016 http://researchlibrary.agric.wa.gov.au/tech_bull/54/.

Payne, AL, Van Vreeswyk, AME, Pringle, HJR, Leighton, KA & Hennig, P 1998, 'An inventory and condition survey of the Sandstone–Yalgoo–Paynes Find area, Western Australia', Technical bulletin 90, Department of Agriculture, Western Australia.

Contact information

Matthew Fletcher
+61 (0)8 9166 4019
Wayne Fletcher
+61 (0)8 9690 2135
Commissioner Soil and Land