THE INTRODUCTION AND ESTABLISHMENT OF THE LARCH SAWFLY PARASITE, MESOLEIUS TENTHREDINIS MORLEY, INTO SOUTHERN MANITOBA (HYMEN.)

Abstract

Definite records of injury by the larch sawfly (Lugaeonematus erichsoni Hartig.) in North America only date back to 1881 when Hagen records the insect from Massachusetts. Horv long it had existed on the continent previous to that date is uncertain, but judging from its distribution at the time it was first reported, we may safely conclude that it had been present for a number of years. There is indeed a significant statement by Audubon in which reference is made to the larches being stripped, by a “green caterpillar some three quarters of an inch in length,” which if referable to this sawfly would take our records back to the beginning of the last century.