Ground cover key to avoid soil loss

Do not forget to look down at ground cover


Farming Small Areas How To
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As much of eastern Australia remains dry heading into autumn and winter, maintaining ground cover becomes even more important, but challenging.

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COVERAGE: This is ground cover at 80 per cent coverage. Good ground cover helps reduce erosion of soils by wind and rain.

COVERAGE: This is ground cover at 80 per cent coverage. Good ground cover helps reduce erosion of soils by wind and rain.

Ground cover is the most effective way to minimise run-off and erosion, as it protects the soil surface and helps to 'hold' the top soil in place. 

Ground cover is defined as ‘any material on or near the soil surface that protects the soil against the erosive action of raindrops and overland flow’.

It can also help reduce erosion of soils by wind. It is usually expressed as a percentage.

Plant material, either alive or dead, is the most common and most important form of ground cover.

Other materials such as loose surface stones, dung and snow can also provide an effective ground cover.

Any grazing plan or strategy should aim to maintain a minimum level of ground cover, effectively meaning something is 'left' after grazing - not all of the pasture resource is used.

Ground cover also plays an important function in promoting soil biological activity, nutrient cycling, and preventing weed spread and germination.

SPARSE: The difference between 65 and 80 per cent ground cover is quite visible despite there being only a 15pc difference.

SPARSE: The difference between 65 and 80 per cent ground cover is quite visible despite there being only a 15pc difference.

There are many different ways of assessing ground cover in pastures, such as visual, photographic and point, linear and area quadrants.

Different methods take different amounts of time, involve different types of equipment, and have different levels of reliability.

The method selected will often depend on needs, type of pasture and convenience.

Ground cover levels will vary across a paddock, between paddocks and over time. This is due to differences in pasture type, plant growth, grazing pressure, grazing habits of stock, paddock aspect and soil type, fertility and moisture.

Typically, in grass-based pastures, once ground cover falls below about 70pc, patches of bare ground join up and both run-off and water erosion increase dramatically.

However, the minimum amount of ground cover required to control run-off and erosion can be affected by slope, rainfall and soil type.

A good start is the Agfact by NSW DPI - search online for Agfact Maintaining ground cover to reduce erosion and sustain production by Des Lang and Warren McDonald.

If the ground cover percentage largely comprises desirable perennial pastures, this helps determine the ability of pasture to regenerate after grazing.

Make some visual assessments of ground cover, in different land types and different paddocks.

If you think some areas don’t meet the minimum ground cover recommendations, think about changing grazing pressure in the area.

There may still be enough time and warm weather to spell pastures, before growth slows down, helping to restore some ground cover.

When rains finally arrive and pasture growth is fast, remember to keep an eye on ground cover.

It is easy to be distracted by the height and bulk, and forget the important role that ground cover plays.

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