Oregon is the world's major producer of cool-season forage and turf grass seed. In the past grass seed fields were uniformly burned after harvest to control weeds, diseases, insect pests. However, due to strong objections from a growing population in Oregon, general open field burning was legislatively phased down beginning in 1991.
There is concern about the impacts of the phase out of burning, and the consequent changes in straw management, on arthropod and related pests in grass seed fields. Pests are largely subterranean or remain close to the ground surface, and include slugs, cutworms, sod webworms, bill bugs and symphylans. In recent years, numbers of crane flies in grass seed fields have increased. The increase in organic matter in unburned fields due to the presence of straw may have resulted in an increase in pest incidence. However, few studies have examined the impacts on pest incidence of straw residue management in unburned fields. In addition, there is little information on post-harvest movement of pests in grass seed fields.
We conducted weekly surveys to determine the species composition of arthropod and related organisms present in grass seed fields. Surveys were conducted during the growing season, and during harvest and post harvest periods. Comparisons were made in species composition and abundances of pests and natural enemies collected at different periods and different locations to determine impacts, if any, of non-thermal post-harvest management practices. This information will be beneficial to growers for determining the pest complex the following year, and for optimizing the use of chemicals for their control. In addition, information on the presence of beneficial insects remaining in the field after harvest will be useful for development of appropriate biological or IPM strategies for grass seed production in Oregon.
The ESA 2001 Annual Meeting - 2001: An Entomological Odyssey of ESA