A friend has a problem wih part of a mature hawthorn hedge whereby some of the branches have a coating of white dust, the leaves are quite small, and some of the wood appears to have no sap.He knew that I had had some experience of Ermine Moth affecting a thorn hedge and phoned to compare notes. He saw no evidence of the web associated with the moth problem and thinks that the hedge may have been hit by chemicals used in the preparation of an adjacent field for a wheat crop. Can anyone shed any light? Thanks