• Myers, Steven Alan
  University of Maine Graduate School
  

The Osystershell sclae, Lepidosaphes ulmi (L.), is a common and widely distributed sap sucking insect which feeds on a variety of fruit trees and many other deciduous trees and shrubs. However, even when very abundant it often goes unnoticed because of it's small size (about 2.8 mm. X 0.7mm.), its sedentary nature, and its lack of similarity to conventional insect form.

The Oystershell scale is of economic importance in the apple growing industry. It causes reduced tree vigor which decreases apple production and also increases susceptibility to other stresses such as disease and other insect pests. Severe infestations may cause dieback or tree mortality but artificial control measures are usually applied before this can happen.