https://defrafarming.blog.gov.uk/sustainable-farming-incentive-pilot-guidance-manage-maize-to-reduce-runoff-and-erosion/
Manage maize to reduce runoff and erosion
The guidance on this page is for SFI pilot participants only. Please visit GOV.UK for the official Sustainable Farming Incentive scheme guidance.
Find out how land managers can reduce runoff and soil erosion when growing and harvesting maize.
If you’re completing this action as part of the Sustainable Farming Incentive pilot, how you do it is up to you.
The advice on this page can help you get better environmental and business benefits, but you do not have to follow it to get paid.
Runoff and soil erosion in maize crops
Maize is planted in wide rows and often harvested in late autumn.
Wide rows leave a lot of bare ground. This increases the risk of runoff and soil erosion as there is no vegetation to trap the soil.
A later harvest when the soil is soft and wet can damage soil structure and cause runoff. It can leave the soil without vegetation to protect it during winter.
Benefits of reducing runoff and soil erosion in maize crops
The benefits are:
- fields retaining fertile topsoil and nutrients, like nitrogen and phosphorus
- cleaner water, as less soil, pesticides and nutrients reach water bodies
- lower risk of flooding, as the flow of water into water bodies is slowed
- more water available for crops, as it infiltrates the soil more easily
- better ground conditions, so farm operations are possible for longer
Choose the right field
Consider if you have fields that are suitable for growing maize. Suitable fields have:
- well drained, light or medium textured soils
- a low or moderate risk of runoff and soil erosion
- little risk of flooding
- little or no direct or indirect connection to water bodies
Drains, farm tracks, gateways and roads can directly or indirectly connect fields to water bodies. Read about how to apply for grants for capital items, including resurfacing of gateways.
Use a risk assessment to identify fields that have a low risk of runoff and soil erosion.
You must follow the farming rules for water. These require you to take steps to stop manure, fertiliser or soil getting into water bodies.
Do not grow maize on areas with historic features, as it’ll damage these features.
How to manage maize to reduce runoff and soil erosion
When establishing maize:
- remove any compaction before sowing
- sow an early maturing maize variety in spring for an earlier harvest
- sow and establish tramlines across slopes
- add manure and fertiliser according to a nutrient management plan
Rotate maize crops around the farm to help:
- avoid a build-up of nutrients from repeated manure and slurry applications
- maintain or improve soil structure
- maintain soil organic matter and reduce compaction and runoff
- reduce a build-up of weeds that are not well controlled by herbicides
Use a cover crop
Grow a cover crop between the maize rows to reduce bare ground. This increases water infiltration and reduces runoff. Cover crops protect against compaction during field operations and at harvest.
You can:
- under-sow between the rows of growing maize, once they have reached 4 to 5 leaves
- establish a cover crop within 2 weeks of harvest
Use fast-growing species that don’t get shaded out, like perennial ryegrass or Italian ryegrass. Cover crops can be single or a mix of species.
Harvest
Harvest maize by the end of September to reduce the risk of soil damage and allow time for the next crop to establish.
Avoid harvesting in wet conditions as this leads to bare compacted soils and increases the risk of runoff and soil erosion.
Remove soil compaction after harvest if the ground conditions allow you to.
How to tell your actions are working
You’ll have:
- a dense cover of vegetation between the growing maize, if you under-sowed a cover crop
- little or no bare ground over winter after maize is harvested
You should not see:
- any channels formed by runoff and soil erosion
- mounds or fans of soil at the bottom of slopes
- water standing for long periods
- deep ruts from harvesting machinery
Look out for:
- clearer water in local water bodies
- more freshwater wildlife, like insect larvae and fish
- less mud on tracks and roads next to fields
You may need to clean your ditches less often, as silt builds up more slowly.
