This agriculture extension service publication from Pennsylvania State University introduces the identification and control of common ornamental insect pests. For each of the insects or insect groups (i.e. aphids) identified in this publication, information on host plants, pest description, and damage caused by the pest is given. Also a calendar of insect problems and suggested control methods is included. This calendar indicates the insect pests, control insecticides, and the recommended concentration of insecticides with some application information according to treatment times. Insects mentioned in this publication are listed alphabetically and include Bagworm, Bronze Birch Borer, Dogwood Borer, Elm Bark Beetle, Gypsy Moth, Japanese Beetle, Lilac Borer, Oak Leafroller, Pine-Needle Scale, San Jose Scale, Spruce Budworm, and White-Pine Weevil. (MR)