Agricultural Extension Service, South Dakota State College
Shrubs and shade trees in full foliage are objects of beauty and should be protected from the ravages of insects. This circular does not attempt to describe all insect pests that may occur on trees and shrubs but rather singles out some of the more important ones that are troublesome in South Dakota. Information on pests not covered herein may be obtained from your County Extension Agent or by writing to the authors at South Dakota State College, Brookings. The insects described are divided into groups depending upon their feeding habits. These groups include the sucking insects, which feed on various plant juices by sucking mouthparts; the leaf-chewing insects which have chewing mouthparts and feed on leaves; the insects attacking branches and trunks and those groups of insects and mites which cause various odd shaped formations on plants known as galls ( gall producers).
Hantsbarger, W.M. and Ferrell, E.K., "Insect Pests of Trees and Shrubs" (1959). SDSU Extension Circulars. 640.