Developing methods to detect parasitoids released for biological control of the emerald ash borer
PARTNERS: USDA Forest Service Forest Health Protection (Northeastern Area), USDA Forest Service Northern Research Station, USDA Animal and Plant Health Inspection Service Plant Protection and Quarantine, USDA Agricultural Research Service, Michigan State University, University of Massachusetts
SUMMARY: Researchers are developing methods to detect three emerald ash borer (EAB) biological control agents (parasitoids) in the interest of optimizing release strategies.
At three parasitoid-release sites with moderate EAB densities in Michigan, researchers will make 1) “egg sentinel logs” by exposing ash logs to egg-laying EAB females and 2) “larval sentinel logs” by inserting EAB larvae into similar logs. Researchers will compare the number of parasitoids recovered from sentinel logs with the number recovered from infested trees. At each of these field sites, researchers will release relatively large numbers of each parasitoid species at multiple time intervals during the field season to facilitate parasitoid establishment and reproduction. The following year, researchers will prepare 1) “egg sentinel trees” by caging EAB females on girdled ash trees and 2) “larval sentinel trees” by girdling and inserting EAB larvae in ash trees. Researchers will compare the number of parasitoids recovered from sentinel logs with the numbers from sentinel trees. Using methods developed over the first two years of the project, researchers will establish sentinel logs or trees at different distances from the parasitoid-release epicenter at each site. Information on parasitoid dispersal distances and population densities will help optimize parasitoid release frequencies and numbers.
EFETAC'S ROLE: This project is supported by EFETAC funding.
STATUS: Ongoing
PROGRESS: In addition to the work described above, researchers and cooperators are deploying yellow pan traps at EAB biocontrol release sites as a simple and inexpensive method to determine parasitoid establishment. Researchers expanded the known establishment and distribution of Spathius agrili (a non-stinging parasitic wasp) at three study sites in Michigan. The yellow pan trap method was provided to the EAB Biocontrol Program, and the traps were deployed in 2011 by land managers in Michigan, Illinois, and West Virginia, and by researchers in Indiana to determine parasitoid establishment at release sites.
Bauer LS, Hansen J, Gould J. 2011. Yellow Pan Traps: A Simple Method for Trapping Larval Parasitoids Released for Biological Control of the Emerald Ash Borer. http://nrs.fs.fed.us/disturbance/invasive_species/eab/local-resources/downloads/YPT_Method.pdf
Hansen, J., L.S. Bauer, and J. Duan. Field detection of introduced emerald ash borer (Agrilus planipennis) parasitoids using larval sentinel logs and yellow pan traps: a proof of concept study. Great Lakes Entomologist. In preparation.
Duan, J.J., L.S. Bauer, M.D. Ulyshen, J.R. Gould, and R. Van Driesche. 2011. Development of methods for the field evaluation of Oobius agrili (Hymenoptera: Encurtidae) in North America, a newly introduced egg parasitoid of emerald ash borer (Coleoptera: Buprestidae). Biological Control 56:170-174.
LINKS:
USDA Forest Service Forest Health Protection (Northeastern Area)
USDA Forest Service Northern Research Station
USDA Animal and Plant Health Inspection Service Plant Protection and Quarantine
USDA Agricultural Research Service
CONTACT: Steve Katovich, Northeastern Area Forest Health Protection, skatovich@fs.fed.us or (651) 649-5264
Updated February 2012
