The Value of Hedgerows

Hedgerows have many values and functions. They can be multi-functional. A diversity of hedgerow types and management on a farm is ideal. The functions of hedgerows include the following:

Shelter - hedgerows provide protection for livestock and crops for up to thirty times their height, a dense base is also more effective.
Scenic appearance – characteristic Irish hedgerow, enhancing the countryside.
Stock enclosure – hedgerows provide long term cost effective stockproof barriers, if well managed. (More height is required here for bird nesting).
Screening can be provided by native species such as whitethorn .
Flooding control –root systems of hedgerows regulate water movement and help prevent flooding.
Disease control –hedgerows help prevent the spread of airborne disease.
Water quality – hedgerows trap silt and soil particles, which clog up fish spawning grounds if they enter watercourses .
Wildlife - as the area of native woodlands in Ireland is small, hedgerows have become very important wildlife habitats in the Irish countryside.
Cultural / Historical – hedgerows are part of Ireland’s cultural, historical and archaeological heritage. Townland boundary hedgerows are particularly important.

Hedgerow as a Wildlife Habitat

As a wildlife habitat, hedgerows provide food, shelter, corridors of movement, nest and hibernation sites for many of our native flora and fauna.

Hedgerow trees – mature trees provide roosts for bats, while saplings just above the height of the hedgerow are important perching posts for birds.
Birds – of the 110 species regularly recorded in the Countryside Bird Survey in Ireland during the breeding season, 55 use hedgerows. Of these, 35 nest in hedgerows over 1.4m high and 1.2m wide, which provide cover from overhead and ground predators.
Cover – hedgerows with a dense base provide cover for small birds and mammals, such as the hedgehog. The barn owl hunts along hedgerows for prey such as the field mouse.
Places for Plants – hedgerows provide places for many native flora, such as the primrose. Flora in turn provides food sources, such as blackberries on the bramble.

Hedgerow as a wildlife habitat

The network of hedgerows allows wildlife to move through the countryside. Birds, bats and butterflies travel along hedgerows, rather than cross open fields.

History

Most Irish hedgerows were planted during the 1700’s and 1800’s. Acts of Parliament were passed in 1697 and 1721, making it obligatory for landowners to erect proper permanent boundaries between their properties. The boundaries were ‘ditches of six feet wide and five feet deep, quicked with whitethorn, crab or other quick-sets’. Where these would not grow, furz was recommended. Other options included a ditch with a dry stone wall or mud wall and in wet ground the banks whereof to be planted with sallows, alder and others.

Hedgerows along townland boundaries often date from medieval times or earlier. Older hedgerows are richer in plant and animal species. They are also of historical and cultural value. Ancient Gaelic bank-and-ditch (clas) originate from as early as the Neolithic and Bronze Agrs (c. 3500-700 BC).

Hedgerow Management

Management depends on the function of the hedgerow. Diversity is most important. Assess the condition of the hedgerow and decide on appropriate management. Management must not occur during the bird-nesting season from March to August.

For further information contact your local Teagasc office or www.teagasc.ie

Published by Teagasc, 19 Sandymount Avenue, Dublin 4.

January 2004