Cover crops reduce soil erosion and run-off

Wind and water erosion often lead to a loss of small particles, like clay and organic matter, from the soil, which are critical to soil fertility. Cover crops provide ground cover during erosion-risk periods.

Water erosion

Heavy rainfall can cause soil erosion. Surface run-off occurs when excess rainfall flows across the soil surface, carrying sediment with it. This can silt up watercourses.

There is a risk of losing phosphorous from the field via run-off or sediment erosion, which can impact water quality and the environment.

Cover crops can combat soil erosion and sediment loss from surface run-off and reduce diffuse pollution risks, if sufficient canopy cover and root establishment are achieved.

Canopy cover prevents high-energy raindrops from hitting the soil directly. Root systems bind and stabilise the soil and improve rainwater infiltration by slowing down the flow of water and creating more soil channels.

Soil cover of 30% can reduce run-off by 50% and erosion by up to 80%

How much the cover crop provides these benefits depends on the species in the seed mixture.

The following species tend to perform well:

Those with high root density, such as oats (influencing soil aggregate stability)
Those with high root thickness, such as radish and chicory (influencing drainage pores)
Those that provide good ground cover, such as oats and brassica mixes
Those that establish rapidy in the autumn, such as mustards

Maize fields can be a significant source of soil erosion. They must be actively managed to reduce the risk of soil, nutrient and agrochemical loss during winter. Cover crops oversown into maize crops can reduce overwinter losses.

The ADAS Farmscoper model helps predict the impact of sowing an autumn cover crop on nitrate, phosphorus, and sediment losses.

Water infiltration test

Improving soil's ability to absorb water during intense rainfall events (infiltration) helps reduce the risk of soil erosion and the associated loss of nutrients from land to water.

Learn about water infiltration tests

Water erosion

Strong winds can blow significant amounts of soil particles off fields.

Cover crops increase surface roughness and reduce the wind speed close to the soil surface, minimising wind erosion.

Root systems also have a binding effect on the soil.

Further information

Find out more about soil management

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Cover Crops Soils Water

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