Rog Wood: 'It's reckoned there are around 180,000 miles of drystane dykes in the UK'

Those dykes should be regarded as an important part of our heritage. They stand as a testimony to the sheer hard graft involved in moving millions of tons of stone, often up incredibly steep hillsides, and the skill of building walls without mortar or cement that have stood for generations.

A well-built dyke should last for over 100 years with little or no attention, but sadly most are now showing signs of neglect.

Dykes are vitally important on a livestock farm. They form an impenetrable field boundary that prevents even the wiliest farm animal from escaping, unlike fences and hedges that can be crawled through or under.

Another great advantage is the shelter they offer. During a storm, the lee-side of a dyke is as cosy as a shed, and many a new-born lamb owes its life to such shelter that saved it perishing from hypothermia.

Birds build nests in them, while small animals and insects also use them for shelter and homes. Even farmers and their workers enjoy sitting in the lee of a dyke to rest or enjoy a tea break.

When I started farming the Government was paying a grant of 50 per cent towards the cost of rebuilding dykes, and my landlord was prepared to meet half of the balance. That left me having to find a quarter of the cost, so I took advantage of the scheme and rebuilt about 2 miles over a four-year period.

The previous tenant in my farm committed what I considered to be a cardinal sin. Instead of rebuilding some dykes that were no longer stock-proof, he used a grant scheme to erect fences at the back of them. As a result, I was unable to claim grant aid to rebuild those dykes, and had to live with the curse of those fences. They prevented livestock from getting close enough to shelter from the bits of dyke still standing when the fence was on the leeward side.

Worse, sick sheep and lambs would often cower between the dyke and fence hidden from view. As a result, I had to make a point of going over to the dilapidated dyke and look up and down the far side.

That all changed about 20 years ago when I took part in an Environmentally Sensitive Area (ESA) scheme that offered to pay 100 per cent of the cost of rebuilding those dykes - about 2000 metres.

It takes about a ton of stone to build a metre of dyke. Each stone has its own particular place in the overall design, so a skilled dyker will survey a random pile of stones, select one, turn it over and then place it precisely where it belongs. I can tell you from experience that is easier said than done.

I seem to have spent many long, weary hours lifting stones. The plough often turns up big stones that need to be removed from the field before it can be cultivated. After every cultivation more stones appear, though you would have thought that over the centuries all the stones must have been removed. Yet they still appear as if they are breeding underground.

It is a strange fact of farm life that just as field stones appear to breed underground, stones originally used to build a dyke mysteriously disappear. Some get trampled out of sight in soft ground by cattle, while bigger ones break up as a result of frost. End result was that the dykers constantly pestered me for extra stones to help them maintain the height of the new dykes.

I carted many from heaps of stones gathered from cultivated fields. Bigger ones needed to strengthen the dykes came from a large heap of rubble created by old buildings I had demolished to make way for modern ones.

It was a lot of hard work, that spanned almost 30 years, but I eventually left my farm with the dykes in tip top condition. I can only hope that succeeding farmers appreciate and maintain them.