https://defrafarming.blog.gov.uk/leave-stubbles-over-winter/
Leave stubbles over winter
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 provide winter food sources and habitat for wildlife by leaving stubbles over winter.
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.
About overwintered stubbles
You can leave crop stubbles on your land after the harvest to benefit wildlife.
Overwintered stubbles are suitable for all farm and soil types. You can leave unmanaged overwintered stubbles across a whole field or a strip. This will provide food and shelter for a range of birds and other wildlife.
Basic overwintered stubbles are those left over winter until February the following year. Enhanced overwintered stubbles are those left over winter until July the following year.
Stubbles can be retained in several areas across a holding. They can link non-crop habitats like hedgerows, ponds and field margins. This can help wildlife move between these habitats, especially in large fields over 20 hectares (ha).
The importance of overwintered stubbles
Keeping enhanced stubbles can:
- reduce autumn workload
- improve cashflow by spreading labour, machinery and variable costs
- reduce hard to control grass weeds such as black-grass
Stubbles can also reduce soil runoff, which improves:
- water quality
- soil health, as nutrients are retained in the soil
Overwintered stubbles provide important winter food sources for seed-eating birds like:
- grey partridges
- corn bunting
- linnet
- reed bunting
- skylark
- tree sparrow
- yellowhammer
They also provide foraging and open ground for wildlife like brown hare.
Stubbles provide habitat for beneficial insects like spiders, which can help reduce pest numbers in crops. This can reduce the need for pesticides, which is an important part of integrated pest management.
Enhanced overwinter stubbles provide additional benefits. They can provide:
- year-round food and shelter for farmland birds, mammals and beneficial invertebrates like predatory beetles, pollinators and ladybirds which eat aphids
- opportunities for ground-nesting birds, mammals and beneficial invertebrates to breed in the spring and summer
- food for chicks in spring by increasing invertebrate numbers
- opportunities for rare arable plants to grow, flower and set seed
- food for pollinators like bees in the spring and summer where arable plants have germinated and flowered
Where to establish overwintered stubbles
Plots should be at least 1ha but those over 10ha are best. Plots should be at least 48 metres wide to reduce the risk of soil runoff.
For strips of overwintered stubble, the best locations are along south-facing boundaries. These allow more beneficial weeds to grow, producing more seeds for birds to eat.
The best fields for stubbles have a low burden of:
- grass weeds like black-grass, reducing the need to spray
- thistles
The best fields for enhanced overwintered stubbles have:
- rare arable plants
- known nesting lapwing populations
- nearby areas of scrub which can provide foraging habitat for turtle doves
Do not use field areas that are at high or very high risk of runoff and soil erosion. You can complete a runoff and soil erosion risk assessment to help you choose the right locations for stubbles.
Avoid steep sloping fields.
Do not use field areas with a known history of hard to control weeds like:
- black-grass
- couch
- docks
- sterile brome
- thistles
- wild oat
This will reduce the need to use herbicides on the unmanaged areas.
How to establish overwintered stubbles
After the harvest, leave the stubble area uncropped and unmanaged until at least the end of February. To get the best benefits, leave them until July the following year.
For cereal crops, only use stubbles that follow the harvest of:
- barley
- canary seed
- oats
- red millet
- rye
- triticale
- wheat
- white millet
For non-cereal crops, only use stubbles that follow the harvest of:
- linseed
- oilseed rape
- quinoa
Do not follow a maize harvest, as this can increase soil erosion and surface runoff, particularly on high-risk fields. If your land is also in the arable and horticultural soils standard, do not use stubbles following a root crop harvest.
Do not:
- cut or graze the area of overwintered stubble
- apply fertilisers like lime
- undersow your crops, as these crops tend to contain fewer weed seeds and spilt grains
To maximise environmental benefits you can:
- establish stubbles near to high-value habitats like hedgerows, scrub and woodland
- establish stubbles close to other seed-rich habitat on your farm
- use fields with a history of nesting lapwing and skylark
- use fields close to areas of scrub suitable for nesting turtle dove
- use warm, sunny, south-facing field headlands known to support rare arable plants
Herbicide use
To increase the benefits to wildlife, do not use:
- pre-harvest desiccants to dry out plants within the preceding crop
- post-harvest pesticides, except for the application of herbicides to control problem grass weeds like black-grass between May and June
Avoid spraying areas containing desirable arable plants like:
- corn spurrey
- red hemp-nettle
- shepherd’s needle
- Venus’s looking-glass
- weasel’s-snout
You can spot spray broad-leaved weeds like common ragwort using a hand lance, knapsack sprayer or weed wiper.
How to enhance stubbles
Consider using fewer herbicides on the previous crop to increase foraging opportunities for wildlife.
To increase the environmental benefits of overwintered stubbles, you can combine them with:
- unharvested low input cereal
- ryegrass seed-set as winter food for birds
- winter supplementary feeding
- autumn-sown winter bird food plots
- supplementary summer feed
You can sow cover crops instead of leaving stubbles.
If you have historic features on your land, find out how you can use shallow cultivation to protect them.
Vary your stubble straw height
Have different stubble heights around your farm to provide the greatest range of habitat for wildlife. You can do this by lowering and raising the combine header.
Skylark and yellowhammer prefer shorter stubble, while other species like grey partridge shelter in taller vegetation.
Taller stubble encourages predators and beneficial insects to colonise the stems.
Shallow cultivate for nesting birds
You can shallow cultivate (using a set of tines or discs) enhanced overwintered stubbles between mid-February and mid-March. This will encourage breeding lapwing and other ground-nesting birds like skylark.
All cultivated nesting plots should be at least 1ha and a minimum of 100 metres wide.
For breeding lapwing cultivated nesting plots are more likely to be successful if they are:
- greater than 2ha
- in the centre of large, open fields
- close to wet or other unimproved grassland
Establish these nesting plots at least 100 metres away from:
- woods
- in-field and hedgerow trees
- buildings
- overhead power-lines
- main roads
- public rights of way
Establish nesting plots at least 200 metres away from wind turbines.
Do not cultivate where it will increase the risk of soil erosion and runoff.
Shallow cultivate for rare arable plants
Cultivating your stubble between mid-February and the end of March can encourage rare arable plants to germinate, flower and set seed.
The best locations for most arable plants are generally sunny, south-facing field headlands. These are typically up to 6 metres wide and next to old farm tracks and field boundaries. These are also ideal for foraging invertebrates like bees, butterflies, flies and moths.
What overwintered stubbles should look like
On basic overwintered stubbles, you’ll see:
- farmland birds and other wildlife, like brown hare, feeding on insects, spilt grains and weed seeds within the stubble
- a patchwork of varying stubble straw height and scattered areas of bare ground and shorter vegetation less than 10cm tall, alongside taller and denser vegetation
- improved water quality in adjacent watercourses as a result of less soil erosion, runoff and diffuse pollution
- no evidence of soil erosion, like gullies or soil wash, localised flooding or pollution occurring within stubbles or off site
- few or no hard to control grass weeds, like black-grass, that need targeted spraying
On enhanced overwintered stubbles, you’ll also see:
- farmland birds feeding on spilt grains and weed seeds in winter, spring and summer
- birds like lapwing and skylark nesting in the spring and summer
- brown hares using plots for breeding, foraging and shelter
- arable plants and some weeds growing among the stubble
- plots containing lots of arable plants of different colours, scents, shapes and heights
- beneficial insects foraging on pollen and nectar in plots
