Wrap up warmly and take the opportunity to appreciate the remainder of the autumn colour on the deciduous trees. The colder nights see the leaves dropping as the abscission layer breaks down. As the leaf falls a barrier has formed on the bud that prevents the ingress of disease and other pathogens into the living tissue, thus keeping the tree in good health. Two that have coloured and lasted this year were the Chinese Euonymus alatus and from eastern North America, the cut leaved Sumach, Rhus typhina ‘Laciniata’.