With the start of the official hedge-cutting season fast approaching, now is a good time to make a plan for the coming months.

How hedgerows are maintained directly affects their usefulness across a range of different farming and environmental services.

There is mounting evidence that hedgerows can play a key role in reducing the negative impacts of climate change and related extreme weather patterns.

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In heatwaves, their role in providing shade and protecting livestock from heat stress and dehydration has been very evident in recent months.

They can greatly reduce flooding by allowing water to infiltrate the soil. They play a vital role in buffering the flow of nutrients: this is recognised in our mandatory nitrates derogation measures.

Their role in protecting and enhancing biodiversity cannot be over-emphasised. For example, in intensively managed farm landscapes, they provide feeding and breeding habitats for two-thirds of our songbird species.

Strong

In general terms, hedges need to be strong and healthy to achieve these important functions.

The development of powerful flail machines has been associated in recent years with a common practice of annual cutting of all the hedges on the farm to a low height, especially, but not exclusively, in tillage situations.

An example of hedgecutting where intermittent bushes are left to grow. \ Hedgerows Ireland

This is associated with a number of problems. Repeated cutting at the same level damages the growing points of the hedge and has the effect of thinning out the base. Ultimately, the hedge will die.

Another recent practice is the use of very powerful mulching heads mounted on track machines which are used to reduce mature tall hedges down to a line of stumps, which are shattered and liable to disease and rotting.

Different sizes and shapes

Ideally, aim to have a range of different hedge sizes and shapes on the farm. This is particularly important for wildlife, but makes economic sense also.

The choice of management will be dictated by a number of factors and requirements: for example, the need for shelter for livestock on exposed sites, access for machinery, sight lines on roadside boundaries, etc.

Hedgerows Ireland warned that the heavy-duty mulching could put the long-term health of a hedge at risk.

Recommendations for hedge management:

  • Develop a multi-annual management plan for your farm's hedges and discuss this with your contractor if you are using one.
  • Identify the historically significant hedges on your farm - townland boundaries, barony boundaries, double ditches, etc. These are irreplaceable.
  • Some hedges provide most benefits to your farm if allowed to develop into a treeline and, depending on your requirements (such as for shelter or privacy), may never need cutting or only side cutting for electric fences and access.
  • Consider cutting some of your hedges on a two- or three-year rotation. This is very good for wildlife, as it allows more plants to flower and fruit.
  • For hedges cut annually, raise the cutting height by a few centimetres each year. This is good for both hedge health and wildlife, as it avoids a damaging 'knuckle' developing at the cutting point and it also allows for flowering and fruiting.
  • Leave intermittent bushes to mature into trees at intervals.

  • Defer cutting as long as you can - ideally cut later in the winter to allow birds and other wildlife to benefit from the feeding and shelter provided by the hedge.
  • Don't use or contract out the use of a mulching head. These have no place in hedge management, as they pulverise and shatter stems, allowing rotting and disease to enter.
  • Hedges should be managed on a long-term cycle, as they can become gappy with time. Many will need to be rejuvenated after 20 to 40 years using coppicing or hedge-laying techniques.
  • Some mature 'veteran' hedges have gone beyond the point where rejuvenation is feasible and should receive minimum intervention. These are often ancient heritage hedgerows and are an important part of the landscape.