. Eastern forest insects . There appears to be one generation per year in southern Can- ada; in Florida there may be five or six. Infestations in rust- infected cones are noticeable as early as April in Florida. By mid- June attacks on second-year cones are also apparent. The spruce coneworm, Doryctria reniculella (Grote), occurs throughout most or all of the forested regions of Canada and as far west as the Lake States in northeastern United States. Its preferred hosts appear to be white spruce and balsam fir, but many other conifers including Sitka, Engelmann, red, black, Norway, and Colorad
. Eastern forest insects . There appears to be one generation per year in southern Can- ada; in Florida there may be five or six. Infestations in rust- infected cones are noticeable as early as April in Florida. By mid- June attacks on second-year cones are also apparent. The spruce coneworm, Doryctria reniculella (Grote), occurs throughout most or all of the forested regions of Canada and as far west as the Lake States in northeastern United States. Its preferred hosts appear to be white spruce and balsam fir, but many other conifers including Sitka, Engelmann, red, black, Norway, and Colorado blue spruces, Douglas fir, larch, and jack pine are also attacked. The adult is usually silvery-gray and has a wing expanse of 22 to 26 mm. The forewings are marked with zig-zag white lines and a white discal spot. Mature larvae are reddish or amber brown, have hairy warts on each body segment, and are about 18 mm. long. In Canada, adults emerge from late June to early August and deposit their eggs singly or in small groups in such places as cracks or fissures in the bark of stems and twigs, in lichens, within the axils of shoots, or between the scales on cones. The eggs hatch in about 10 days, and the young larvae, without feed- ing, spin hibernaculae in which they spend the winter. When they become active again in the spring, they usually mine one or two needles and then move to and bore into buds, staminate flowers, or cones. During certain years, this species takes a heavy toll of white spruce seed (495). 355
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Keywords: ., bookcentury1900, bookcollectionbiodive, booksubjectforestinsects
