Studies were conducted under controlled laboratory conditions to determine the effect of temperature on development and oviposition of the variegated cutworm, Peridroma saucia (Hübner). Developmental thresholds and Celsius degree days necessary for completion of a given stage are: egg (threshold 5.6°C) = 89 DD; larvae (threshold 6.2°C) = 387 DD; pupa (threshold 8.5°C) = 210 DD; and total development (threshold 7.2°C) = 676 DD. The threshold for oviposition was 3.5°C with 128 DD necessary for oviposition to occur.
Light trap catches of variegated cutworm moths from 1965 to 1979 were plotted as a function of accumulated heat units based on laboratory data. For the 15-year period, peaks of activity occur at 500 and 1200 DD based on 7.2°C threshold. The data generated in this study would be utilized best in an alert network for determining when scouting should occur, based on peak capture of variegated cutworm moths.