RESUMEN
Over a period of 19 yr, the harvestman (Opiliones) community associated with the lowbush blueberry agro-ecosystem in Maine was studied. Eight species representing five genera, four subfamilies, and two families of harvestmen belonging to the suborder Eupnoi were collected. The harvestman community was dominated by two introduced, synanthropic species: Phalangium opilio in all but 1 yr (that year dominated by Rilaena triangularis). Rilaena was recorded for the first time from eastern North America. Relative abundance of harvestman adults increases throughout the season and the temporal pattern of trap capture does not refute speculated life cycles of the harvestmen being univoltine with overwintering eggs. Some blueberry management practices were found to affect trap capture. We did find that on average (with opposite results 1 yr) trap captures are greater in pruned fields than in fruit-bearing fields. Organic fields were found to have higher relative abundance of harvestmen than conventionally managed fields. Conventionally managed fields with reduced-risk insecticides showed no difference in harvestmen relative abundance compared with those conventionally managed fields using the older more persistent organophosphate insecticides. Insecticide trials with common insecticides used in blueberry insect pest management showed that the organophosphate insecticide, phosmet, and the pyrethroid insecticide, esfenvalerate, were detrimental to P. opilio adults when exposed to leaf residues, whereas the reduced-risk insecticide, spinosad, showed no negative effects compared with nonsprayed foliage.
Asunto(s)
Arácnidos/fisiología , Arándanos Azules (Planta) , Animales , Arácnidos/crecimiento & desarrollo , Biota , Ambiente , Cadena Alimentaria , Control de Insectos/métodos , Insecticidas/efectos adversos , Maine , Ninfa/crecimiento & desarrollo , Ninfa/fisiología , Óvulo/crecimiento & desarrollo , Óvulo/fisiología , Dinámica Poblacional , Estaciones del Año , Especificidad de la EspecieRESUMEN
Mean catches of spruce budworm,Choristoneura fumiferana (Clemens), moths were not significantly different among four small-tree thinning treatments of young spruce-fir-hemlock regeneration. Significant inverse relationships were found between trap catches and distances to nearby spruce-fir-hemlock overstory. Prevailing wind directions indicated that moths were attracted anemotactically to upwind pheromone sources. No definite trends were detected between catches and temperature or precipitation.
RESUMEN
Eâ¶Z blends of (E)-11-tetradecenal were field tested (three experiments) for their attractiveness to male spruce budworm,Choristoneura fumiferana (Clemens), moths in northern Maine. Blends of 92.5-99%E isomer caught the most moths (three experiments); blend 95%E had the highest cumulative catch throughout two experiments. Rates of catch per hour for the four most attractive blends (92.5-99%E) showed highly variable responses among experiments; however, similarities were noted for rates of catch within the same experiment. For all experiments and observation hours, blend 95%E had the highest mean rate of catch.