Major Insect Pests of Ornamental Trees and Shrubs
The vast number of plant species makes it difficult to identify the multitude of insects and mites which may attack each plant. Unlike agronomic or greenhouse crops, ornamental trees and shrubs are established in an area for a long period of time, and pest infestations may be sporadic from year to year. Bagworms feed on many kinds of evergreen and deciduous ornamentals. If there is a heavy infestation, bagworms will strip evergreens of their foliage and cause mortality. Deciduous trees are rarely damaged to that extent. The common Lepidoptera which bore into stems and wood of ornamentals usually belong to three families: the clearwing moths (Family Sesiidae), the carpenterworms and leopard moths (Family Cossidae), and twig, tip or shoot moths (Family Torticidae). Control strategies include the removal of infested trees to reduce further infestation. Chemical measures are preventive treatments aimed at egg-laying adults and/or newly hatched larvae prior to entering the tree.