Field Evaluation of Steinernema feltiae Against the Web-spinning Larch Sawfly Cephalcia lariciphila

  • Ramon Georgis
  • Nigel G. M. Hague


Field trials were conducted in Rheola Forest, Wales, Great Britain, to determine the effectiveness of Steinernema feltiae UK strain in controlling the web-spinning larch sawfly Cephalcia lariciphila. Foliar sprays at the rate of 5,000-20,000 nematodes/100 cm branch resulted in 3.4-29.4% infection of sawfly larvae. Soil application of 200 nematodes/cm² resulted in 61% infection of sawfly prepupae and 17.3% of pupae. Prepupal infection ranged from 4.8 to 14.7% 1 year after nematode application. Soil applications of this nematode show that it has potential for biological control of sawfly prepupae. Key words: biological control, Cephalcia lariciphila, entomogenous nematode, persistence, Steinernema feltiae.