Concern has been expressed by a number of residents over the plight of many of the Horse Chestnut trees throughout Dulwich, and indeed, London.
Leaves appear scorched, and finally shrivel and turn brown, giving the impression that the tree is dying. There is also an infestation of small flies around the trees which are extremely annoying. The flies are actually very small moths known as Horse chestnut leaf miner (Cameraria Ohridella) which was first observed in Northern Greece in the late 1970's and has since spread throughout Europe, arriving in Wimbledon during 2002.
Leaf fall as early as August can result in the tree appearing autumnal although so far no trees have died or declined in health as a direct consequence of attack by the moth, however, the added stress to a tree causes concern especially in drought conditions'
There is no known cure for the pest, but limited research has established that leaves should be collected after dropping and either burnt or well dug in to compost. The pupae appear to be extremely frost tolerant, reportedly surviving in temperatures as low as -23C in Hungary. It has been estimated that 1 kg of over wintering leaves could result in the emergence of 4500 moths the following spring. It is therefore essential to destroy affected leaves where possible.
Further information can be obtained from: Entomology Branch, Forest Research, Alice Holt Lodge, Farnham, Surrey. (tel: 01420 22255) email: This e-mail address is being protected from spambots. You need JavaScript enabled to view it
Tony George
Trees Consultant, The Dulwich Estate
The Dulwich Society Trees Committee have invited Professor Julian Evans OBE who was formerly the Forestry Commission's Chief Research officer, to talk about the trees of the National Trust and also about his experiences in maintaining his own piece of private woodland, on Thursday 19 October at 8pm at the St Barnabas Centre, Calton Avenue.
