Since the mid 1970's Cornwall, like the rest of England, has seen a dramatic and catastrophic change in it's landscape due to elm disease. Lost are the rows of tall hedgerow trees which protected crops, buildings and stock from the ravages of the Cornish weather. Gone is the local material for the Cornish Gigs. Or is it?
This section aims to describe the importance of elms and their distribution in Cornwall, explain the nature of elm disease, and give some hope for elms in Cornwall for the future. It will also attempt to answer some of the frequently asked questions about elms and elm disease.
What type of Elms are found in Cornwall?
Elms are particularly difficult to identify and there has been much confusion in their naming over the years. It is not possible to go into a great amount of scientific detail here. There are however a number of species/varieties found in Cornwall including the Dutch elm with its characteristic corky bark on the young twigs.
The distinctive "Cornish Elm" (Ulmus stricta) with its erect leafy branches and small leaves was once the dominant hedgerow tree in many parts of Cornwall. It was especially noticeable in exposed coastal areas where it was often the only tree to be found.
Davey's elm (Ulmus daveyi), which looks like a hybrid between the native wych elm and the smooth-leaved elm (of which 'Cornish Elm' is a variety) is to be found in some parts of the County, notably around Gulval, Newquay, the Roseland and St Kew. Although, like all elms, it is susceptible to elm disease it does appear to be more resistant to the disease than many other varieties and many mature trees survive even today.
The European White elm (Ulmus laevis) was planted in a few locations as an ornamental tree and mature specimens survive today near Calstock, Torpoint and Truro.
Most elm varieties are clones. Indeed Cornish Elms across Cornwall, Devon and Brittany (from where it is thought to have been introduced to Cornwall in the Roman or Anglo Saxon periods) have been shown to be genetically identical. This has undoubtedly led to their susceptibility to elm disease.
Why were Elms common in Cornwall?
Elms are not often found in woodland, but have become ideally suited to farmland and around farm buildings and have thus become established as the most common hedgerow tree. They are: -
- Easily propagated from suckers and cuttings
- Fast growing
- Quite long lived
- Suitable for pollarding and coppicing
- Provide a useful timber
- And, most important in Cornwall, are extremely salt resistant.
Often called Dutch Elm Disease it is caused by a wilt virus that is spread by Elm Bark Beetles which feed on young twigs. The fungus spreads down the vascular tissue, blocking it, causing the leaves and twigs to wilt and go on to kill whole branches and the tree. The disease can remain active for several years in the root system and re infections can occur from the roots. The disease can also spread from tree to tree along their common root system.
For further information on Elm disease please go to the Forestry Commission's Dutch elm disease in Britain web page.
Elm Disease - Further Reading
- Forestry Commission Booklet 42: Field Recognition of British Elms (1974).
- Field Guide to the Trees of Britain and Northern Ireland, Alan Mitchell. Collins.
- The History of the Countryside, Oliver Rackham. Dent (1986).
- An Epitaph for the Elm, Gerald Wilkinson. Hutchinson (1978).
- Forestry Commission Research Information Note 252 Dutch Elm Disease in Britain.