Evaluation of an integrated management and compliance program for Tomicus piniperda (Coleoptera: Scolytidae) in pine christmas tree fields

The pine shoot beetle, Tomicus piniperda L., is an exotic pest that breeds in phloem of recently cut or dying pine logs, stumps, and slash. Adults feed in shoots of live pines to complete maturation. After T. piniperda was discovered in North America in 1992, federal and state quarantines were imposed to regulate movement of pine Christmas trees, logs, and nursery stock out of infested counties. Currently, pine Christmas tree fields must be inspected in the fall and certified as free of T, piniperda before trees can be shipped out of quarantined areas. We developed an integrated program to manage T. piniperda in pine Christmas tree fields. Components of the program include sanitation to reduce availability of cut trees and stumps that serve as brood material, use of trap logs to attract parent beetles into cut trees which are subsequently destroyed, and an insecticide spray to control shoot-feeding beetles. This management program was formalized into a Compliance Program in cooperation with regulatory agencies and tested in 1995 and 1996 in a total of 48 Christmas tree fields in Michigan and Indiana. We periodically surveyed fields and growers to assess compliance with program requirements, levels of T. piniperda shoot damage, and feasibility of the management activities. In fields where all program requirements were completed, percentage of trees with T. piniperda shoot-feeding damage ranged from 0 to 4%. In comparison, shoot-feeding damage was observed on 28-67% of trees in unmanaged fields where brood material was available for colonization by parent beetles. Information provided by cooperating growers indicated that Compliance Program activities could be readily integrated into standard production practices. Adoption of a regulatory policy that inspects compliance with the year-round management program rather than inspecting fields just before harvest is likely to result in sustained T. piniperda control and a more uniform application of regulatory standards to reduce the risk of spread of an exotic pest.