With more funding available to rejuvenate arable hedges, now is a good time to assess their health and restore their potential to be thriving habitats..

Hedges are the single biggest habitat, but they are often taken for granted, says Farming and Wildlife Advisory Group (FWAG) farm environment adviser Rebecca Inman.

They offer landscape-scale connectivity like arteries in the landscape, connecting features such as woodland and flower margins.

See also: How arable farmers can introduce SFI 2023’s no insecticide option

They also bring other benefits, acting as wind breaks in fields to reduce wind erosion risk and hosting beneficials such as crop pollinators and predators of crop pests.

Rebecca believes it’s a case of how to manage them rather than view them as an inconvenience.

However, she acknowledges that they are a cost, requiring some degree of management.

But the good news is that Defra has recognised the cost of managing hedges and has significantly improved the funding that is available through SFI, which allows stacking of payments (see panel).

First step

For farmers looking to rejuvenate their arable hedges, she says the first step is to assess their health and determine what stage of the lifecycle they are at.

“Hedges are dynamic and go through a natural cycle.”

Are they nearing the end and need coppicing/laying, or are they much younger and require less frequent and harsh flailing?

Rebecca points to the Healthy Hedgerows app that farmers can use. With just a handful of questions, it will indicate their lifecycle stage, as well as giving management advice that will help them flourish.

She advises farmers take the time to come up with tailored plans for each hedge, instead of taking a blanket approach across the farm.

This is something that SFI is encouraging farmers to do with money available to do this.

If farmers are not sure how to do this, she suggests getting someone in for guidance such as a FWAG adviser. Farmers will then have the confidence to do the rest of the hedges on their own.

Gap filling

For gaps, it depends where in the cycle they are and their size. If the hedge is bushy, it may be better to coppice and replant the gaps. If it isn’t too bushy, then farmers can simply plant up the gaps.

When replanting, look at what species are already growing in hedges around the area to see what grows best on that soil, thrives in the local climate and is in keeping with the character of the landscape.

These will usually include hawthorn or blackthorn because of their good stock-proofing qualities, hazel in the South West and elm in Essex. One or more of these three species will normally comprise at least 60% of the planting mix.

She points out that hedges on chalk tend to be more species-rich and farmers should try to mimic that in the replanted gaps.

Rebecca adds that having more species in a hedge makes it more resilient to changes in the climate, or to new pests. Some species may suffer more than others from climate changes.

However, she warns farmers not to try to shoehorn a species in the mix that doesn’t belong in that area, as they may struggle in the conditions.

The way farmers intend to manage their newly planted hedges in the long term may also influence which species they plant. For example, hawthorn, blackthorn and hazel can withstand regular trimming.

Most broad-leaved trees and shrubs coppice well, with the exception of beech. Dogwood, spindle and guelder-rose are difficult to lay.

Timing-wise, new hedges can be planted between the end of October and the end of March. Generally it’s best to plant early in the season, before January, to allow the plants more time to establish a network of feeder roots before the onset of spring.

However, if planting into clay soils, it may be best to wait until the beginning of March as heavy frosts can cause frost heave and expose roots. Also, there is a risk that roots will rot in poorly draining soil if planted early.

Ideally, farmers should plant on a still, moist day, to minimise root drying and stress to the plants.

Trees

Hedgerow trees are an important feature and are also included in the SFI actions.

Ash is a common hedgerow tree and with the potential loss of these to dieback, farmers may need to start looking at the next generation of hedgerow trees so new trees

already there when/if ash starts to disappear.

Alternatives include oak, field maple and in some areas sycamore. Crab apple trees are smaller, but have the bonus of providing fruit to birds and mammals.

So how many trees should a farmer aim for? Rebecca says that Defra suggests in SFI four for every 100m, which is one every 25m, which gives plenty of space for them to grow and not shade out the hedge below.

But some areas like the rolling chalk landscape are more open with fewer trees. Again, she suggests getting local advice, as it may not be appropriate to plant lots of trees in a landscape where there weren’t any before.

Over-flailed hedges

For those hedges that have been flailed too hard over a number of years and with not much growth, the best approach may be to coppice and allow it to regrow from the bottom.

This will, with the right management and gap filling, result in a more dense hedge.

For hedges in slightly better condition, she suggests not flailing as hard and letting them incrementally grow 10-15cm a year. This will give them more space to breath and go through their natural cycle.

“If you keep going back to the same growing point, it puts the hedge under stress and will weaken it. Eventually, some plants will die, leading to gaps.”

Once hedges reach the ideal width, allow them to grow upwards 10-15cm each year. Rebecca says 2m is a good minimum width, as this provides shelter and nesting birds will be less susceptible to predators.

Another practice that can benefit nature is to flail one in three years, as this will allow more flowers and berries. However, she warns that this approach doesn’t suit all hedges, such as elm in Essex.

“Elm is vigorous and after three years will be difficult to flail.”

After 15-20 years of incremental growth, hedges will end up being quite large and this is the time to layer or coppice them to start the natural cycle again.

Coppicing and laying can be funded by countryside stewardship grants. Rebecca says laying hedges is seen more in the West, being more stock-proof. In the East where stock-proofing is less essential, you see more coppicing. Coppicing can look drastic, but the hedge will regrow and come back to start the cycle again.

Buffer strips

But its not just hedges, Rebecca suggests farmer also consider having a buffer strip – it could be grass- or flower-rich.

This acts as a buffer for fertiliser and chemicals while also increasing the benefits to nature, by supporting more species of mammals and birds.

These strips can again be funded by CS or SFI.

Her last piece of advice is to stop thinking of neatness and having a blanket approach. What farmers should aim for is a range of hedges and should get away from thinking they must all be neat and tidy, and all the same size.