Abstract
The known distribution of Thymelicus lineola (Ochs.) now includes large areas in Ontario. Spot infestations are recorded from such widely separated areas as Lanoraie and Montreal, Quebec; Ottawa, Sault Ste. Marie, and Fort William, Ontario; and Terrace, British Columbia.Infestations of T. lineola can be reduced by cutting infested areas during June, before adults emerge, or by spraying with Thuricide 90T at the rate of 2 pints per acre. The biology of the European parasite Stenichneumon scutellator Grav. is being studied prior to possible release.