Effects of planting date on damage caused by the banded sunflower moth (Lepidoptera: Cochylidae) in the Northern Great Plains

A 3-yr (1981, 1982, 1986) planting-date study of sunflower, Helianthus annuus L., was done at four sites. Achene damage caused by the banded sunflower moth, Cochylis hospes (Walsingham), was highest in sunflower planted early and lowest in sunflower planted late. Achene weight was highest in sunflower planted early in 1982 and 1986 and highest in sunflower planted late in 1981. The mean percentage of oil content varied among years and location. Planting sunflowers late in southeastern North Dakota and northwestern Minnesota can reduce moth damage without appreciably reducing achene weight and oil content