Disease resistant elms

Progress report

by Ian Bushell

On April 10th we checked the fifteen Dutch Elm Disease Resistant trees, donated by Peter Shallcross and Frank Crosier, that we had planted in April 2021.

Their planting had been delayed for a year by the first COVID19 lockdown in the spring of 2020 (while the saplings sojourned in my garden) and we worried that last year’s drought could have been very bad for trees that had only been in the ground for a year.

These were cultivars from three trees: Ulmus minor ‘Ademuz‘ and Ulmus minor Fuente d’Umbria, both individual trees discovered on mainland Europe and found to have naturally high resistance to Dutch Elm Disease, and Ulmus lutèce, a fourth generation complex hybrid raised specifically to be disease resistant at the Dorschkamp Research Institute for Forestry in Holland.

We had planted these saplings along the hedge line between Sleepers and Cornfield, from Puddle Corner to Oak 5552 and then on along the same hedge line towards the picnic area. This is where a rare and endangered White Letter Hairstreak butterfly (Satyrium w-album) was seen in 2017. White Letter Hairstreaks live their whole life high in the tops of Elm trees and the possibility of a colony in the reserve’s few surviving Elms is what prompted our search for DED Resistant trees

Checking along the Sheep Field hedge line, of the nine trees we had planted in 2021 two had died so these were replaced with two of the five DED resistant elm trees acquired for us this year by Connor Stapleton-Goddard, Wiltshire Wildlife’s Water Team Projects Officer. As we worked our way along the hedge, we found no more casualties and we cleared areas for the three remaining saplings.

Difficult and painful work in a tangle of Blackthorn and Bramble but we were serenaded all the way by Chiffchaffs and Wrens.

The five trees from Wiltshire Wildlife Trust are U.minor x U. ‘Wingam’. U.’Wingam’ is another complex hybrid, this time of two Asian and two European species and its reputation is for exceptional resistance to Dutch Elm Disease.

We are hoping for a little more rain than we had last summer, the new saplings will struggle if there is another drought and we will have to get out the watering cans again.