This handbook is designed to enable people who are interested in trees to identify the insects and mites causing damage to them. About450 species of insects and mites that have caused noteworthy damage to hardwood trees in Canada east of the Rocky Mountains are included. Identification is based initially on the kind of tree damaged, and the insects are grouped under 20 tree genera. Within each host tree section, flow-chart keys, understandable to the layperson, are provided to lead the reader to individual species or groups of similar organisms, with full-colour illustrations to confirm the identity of the insect or mite. The accompanying biological sketch for each insect or mite usually includes information on the necessity for control, based largely on Forest Insect and Disease Survey records. Where control is necessary, methods are suggested. Common names of insects are also given in the text.