Known as "the Devil's rope", despised by the Native American's, the cattle driving cowboys and anyone like myself with a drawer full of ripped trousers. The invention of barbed wire had a dramatic effect on the great American plains and continues to impede movement through a gappy hedge. It's not unusual to see the stone walls and hedges of Mourne topped with a few strands of wire; while this may deter the hill walker, the barbs are less effective at containing sheep. The primary function of the tall, unkempt, Irish field boundaries was not to contain stock but to provide shelter, mark boundaries, improve drainage or clear rock strewn fields. Farmers, once encouraged to rip out mature hedgerows are now advised to retain their field margins for aesthetic, historic and environmental reasons. The age of a hedge has finally arrived. The actual age of an ancient hedgerow, of which there are few if any in Ireland, can be roughly determined by counting a century for each distinct occurrence of a native plant. The guide is only rough, the one I helped plant at the weekend consisted only of hawthorn, local provenance whips purchased from the Conservation Volunteer's tree nursery in Clandyboye. Local provenance basically means the plants are adapted to the local environment and in tune with our seasons. Foreign hawthorn's bud at the wrong time and are less beneficial to indigenous wildlife. The boundary I helped restore was a cross between a hedge and a banked wall known as a 'Louth ditch'. This one will eventually be stock proof; in the meantime it is protected by a quickly erected fence. The wire and post option may be quick and easy to construct but is even less attractive to the yellow-tail moths, and hawthorn shield-bugs who rely on native hawthorn, than it is to me.