In 1974, extensive seedling mortality, attributable to cutworm feeding, occurred on the "Sue fire" plantation.Īlthough few in number, the most severe or extensive epidemics in North America have, within a given region, occurred at about 20-year intervals, lasting for 2, 3 and, in one instance, 4 years. ![]() The effect of defoliation of seedlings and bud and twig tip damage varies considerably with soil moisture and degree of establishment of the seedlings. Herbaceous foliage is preferred when present however, when cutworm larvae are abundant and such foliage is sparse, they accept and may completely defoliate conifer seedlings. Heaviest concentrations of cutworm larvae have appeared on clearings burned over the previous year or two. There is some suggestion that a series of warm, dry years precedes a black army cutworm epidemic and that warm dry conditions during egg laying and hatching are necessary for development of infestations. Feeding was completed in the valley bottoms about the second week in June it continued for a week or two longer at higher altitudes. in began after sunrise: night hours were frequently too cool for larval activity. Feeding on sprouting vegetation begins shortly after the snows recede in spring. Eggs hatch late in the fall and the young larvae overwinter in the soil. Moths fly late in summer and oviposit in the soil, frequently on burned areas. Recently, it has become a pest of planted conifer seedlings in central British Columbia. The black army cutworm, Actebia fennica (Tauscher), has long been a sporadic pest of herbaceous agricultural crops in the northern hemisphere. ![]() Series: Information Report (PFC - Victoria) ![]() Canadian Forest Service, Pacific Forest Research Centre, Victoria, BC. The black army cutworm Actebia fennica (Tauscher) in British Columbia.
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