The 1st of March is the start of the hedge cutting season. Hedge cutting is allegedly illegal from then to the end of August but this does not deter some people and this is disastrous for our birds, insects and small mammals.
Here is a short article about the value of our hedges and more environmentally sound ways to grow and manage them adapted from some articles originally written for the IWT
Hedgerows may be a habitat that was originally planted by humans but then we are part of nature too and these habitats serve many valuable purposes. They act as windbreaks, help with land drainage and healthy water tables, and provide food and shelter for many small mammals, birds and insects. Hedgerows also act as ‘highways’ for these creatures to travel along and as reservoirs for many native species. Hedges are like miniature woodlands and within a healthy hedge there are several layers of growth as there are in a woodland. Our hedges are especially important here, due to the low level of forestation on this island.
Traditionally hedges were maintained by laying but sadly today this art is rarely practiced. It is good to see that there are people beginning to re-introduce this craft which, although labour intensive, makes for a far healthier hedge and one that looks much more pleasing. Hedges need good care. According to the website of the Hedge laying Association of Ireland (http://www.hedgelaying.ie) many of our hedges were planted over 100 years ago.
Within a healthy hedgerow there may be several layers of growth. There may be some mature trees of our native species such as Oak, Ash, Holly, Wych Elm, Crab Apple, Wild Cherry, Bird Cherry, Whitebeam, Willow and Rowan. Some of these species do well when managed as hedging, others do not. The ones that fare particularly well include many of our native shrubs; Holly, Hawthorn, Guelder Rose, Wild Roses, Blackthorn, Gorse, Willow and native Privet. Elder and Spindle also occur in hedges. In some areas there will be a predominance of naturalized species such as the Fuschia and Escallonia. It is good to recognize that some naturalized species integrate well and enrich the hedge, providing food for our fauna and insect life. Others do not and are less desirable such as the Rhododendrons.
Woven through a healthy hedge there will be some of our native climbers: Wild Roses, Honeysuckles, Brambles, Field Bindweed and Ivy, as well as naturalized climbers like Traveller’s Joy (wild Clematis) and Large Bindweed. It is worth pointing out that Ivy is a very valuable food plant for bees in the autumn and is the overwintering habitat of some of our native caterpillars.
At the foot of a hedge there can be a great diversity of some of our native wild flowers such as Ground Ivy, Primrose, Violets, Bluebells, Forget-Me-Nots, Wild Strawberries, Vetches, Cow Parsley, Foxgloves, Red Campion, Chickweeds, Speedwells and maybe a few early Purple Orchids.
These are just some of the plants that will grow in a hedgerow. Often other woodland plants, meadow plants or wasteland plants may join the ecosystem. There may be garden escapes and naturalised species such as Butterbur, Montbretia, Rosebay Willowherb, Wallflowers, Oxalis, Buddleia, Alexanders, Three Cornered Leek, Daffodils or, less popularly, Japanese Knotweed.
Hedgerows can be seen as part of our woodlands and fundamentally important with our low level of woodland cover. They are a rich source of all sorts of fruits and berries that can be used in forage food recipes, hedgerow wines and herbal medicines. Some of the wild flowers such as Ground Ivy used to be used to brew ale before Hops became the main herb used in beer and many of them are delicious wild greens. Many of the plants have delightful folklore attached to them.
A well-managed hedgerow is a rich ecosystem. It is really worthwhile to plant a native hedgerow if you have space for one as it will attract more birds and insects than a non-native hedge. It is really worthwhile reminding farmers and growers that hedges should not be cut during the nesting season (1st March – 31st August) to protect the dwindling numbers of our wonderful birds.
There are some good videos on the importance of hedgerow habitats at http://www.bbc.co.uk/nature/habitats/hedge
To help to identify the plant species in our hedges and other habitats you might be exploring you can take a look at this website http://www.irishwildflowers.ie/ for some good photos.
People may think that good hedgerow management takes a lot of time and costs a lot, but managing a hedge well does not have to take a lot of either. A well managed hedge provides such a rich habitat for so many species of birds, small mammals, insects and plants and really is a great part of the country landscape (and the urban one too).
One of the best ways of managing a hedge is by hedgelaying but this does take time in the inital stages and requires skill. However, there are other ways of managing hedges that look better than the ‘short back and sides’ approach and take less time.
The hedge as a habitat is not just a line of shrubs. It is great to look at hedges as a network and join up any gaps between hedges by plantng in new ones. As well as the shrubs and trees the hedge habitat includes any mature trees, the margin and any ditches running along the hedge line. The hedgerow is made up of individual plants and it is important that if gaps occur in the hedge network due to one plant gettng sick or reaching end of its natural lifespan that replanting is done . Good hedgerow management will tend to help plants remain healthy and live long and prosper.
If planting new hedges make sure that the species of shrub chosen are appropriate to the location and that they are native species that support other wildlife species.
Alternatively, a hedge may be rejuvenated by laying or coppicing (cutting down to near ground level).
At first a newly planted hedge needs to be trimmed every year for the first 5 years to ensure a good dense structure, especially at the base of the hedge. A wide, thick hedge provides more shelter for birds and animals so aim for the hedge to be at least 1.5 metres thick. Any cutting that is done should not be carried out during the nesting season – from 1st March to 31st August.
After this the hedge only needs trimming every 3 or more years. One approach is to just trim one side or the top every couple of years in rotation. This allows the fruiting shrubs and trees (for example hawthorn, sloe, wild rose) to produce berries which helps with rejuvenation. If there are mature trees in the hedge then leave these tall. Over this period the hedge is allowed to gain height and width and this is continued for about 20 years.
Once the hedge starts having gaps at the base it should be left to grow for a number of years before rejuvenating and starting the cycle again..
On a farm it is ideal to plan a range of hedge heights to provide habitats for a wide variety of birds species..
As well as considering the hedge itself allow some outgrowths of plants such as rose, bramble and elm to encourage various butterflies and small mammals. Leave a good margin at the base of the hedge to allow thick grass growth and a good diversity of native flowers; these look beautiful and provide food for bees, butterflies and small birds.
If there are ditches or water channels running by the hedge then ensure that they are cleaned out every 5 years and overhanging branches are trimmed back. Also, do not spread or spray fertilsers and pesticides any nearer than 2 metres to ditches and hedge bases.
If hedges are well managed it does not take a lot of time and the increase in diversity of birds, butterflies, moths, other species and flower species is quite phenomenal over a few years.
The second link below is to a pdf giving great detail and ideas about how to manage hedges well and economically.
Some useful links:
 Hedge laying is the art of cutting hedgerow tree trunks partly through near ground level so that they will bend without breaking and will continue to grow. The laid stems are arranged to form a stock proof barrier. New growth comes from the cut stump rejuvenating the hedge and thickening up the base.