Once a commonplace tree, elm was favoured for furniture making and wheel building for its dense grain and strength as well as its use with water, for bridges and even pipes, due to its durability. These days however elm is rather absent from the landscape particularly in its larger, older forms. The majority succumbed to a fungus spread by beetles best known as Dutch elm disease that saw a rapid drop in elm numbers since the 1960’s.
The Dutch part of its name comes from much of the early study of the disease being conducted in the Netherlands. Beetle larvae hatch and grow from dead elm, picking up spores from the fungus as they grow. When they become beetles they fly off in search of fresh elm bark to feed on, at which point they introduce the fungus to a new tree and the cycle starts again. The beetles favour trees over 20 years old and few elms make it beyond 30 years. Even their regeneration is thwarted by the fungus.
The Conservation Foundation has set up The Great British Elm Project to try and bring this once common tree back to our landscape. On a positive note not all elms have succumbed to the disease. This could be through isolation or, as the project hopes to find and benefit from, a natural borne resistance to the disease. Cuttings have been taken from a selection of these survivors that have lived through the last 60 years and continue to thrive. The project has distributed these now saplings around the country where they are to be grown on and monitored to see if the survivors hold the key to the future.
Having seen the effect of the disease and its ongoing breakdown of trees, just as they seem to be getting into their stride, to come across this project towards the end of last year certainly got our attention. Our five trees arrived in March which was getting close to the end of the planting season as sap was starting to rise, so we decided not to plant them out this year. For now they have been potted up into bigger pots of compost and placed in our tree nursery. This will give us the chance to plant them at a better time of year as well as giving them time to become slightly more hardy trees.
This project comes at a good time. With the threat of Chalara fraxinea, there is the risk of a disease that could seriously reduce our woodland cover as it threatens one of our most prolific trees, the ash. Ash and elm favour a lot of similar conditions, so if ash were to be seriously affected, it would be great to have a viable elm population that could help fill the gap.
We have a few thoughts on where to plant them out, certainly at Clytha in Monmouthshire where we see existing elms getting knocked back each time. We will probably also add some to the new planting at the Skirrid car park, near Abergavenny, where they will be visible below the ancient woodland that covers the southern slopes. As for the remaining one or two, we still have a few months to decide, so will be keeping an eye out for suitable spots across our sites.
Tim – Woodland Ranger