Invasive Species Compendium

Detailed coverage of invasive species threatening livelihoods and the environment worldwide

Abstract

Cone and seed insect phenology in a Douglas-fir seed orchard during three years in western Oregon.

Abstract

Seasonal patterns of cone and seed insect activity and seed loss relative to cone production and weather patterns were examined in 1989-91 in a Pseudotsuga menziesii seed orchard in western Oregon. Six insect species showed distinct patterns of occurrence and cone or seed damage during this period. Lepesoma lecontei, Contarinia oregonensis, Barbara colfaxiana and Dioryctria abietivorella damaged cones or seed exposed during late April each year. Megastigmus spermotrophus damaged seed in cones exposed during May and June. Leptoglossus occidentalis was most damaging in cones exposed during July-August.