. Bulletin of the Department of Agriculture. Agriculture. CYPRESS BARK SCALE. 17 October and NoA^ember. These mate and die in a few days. At this time most of the females have cast their hist skin and are about one- half grown. The winter is passed as adult females, with no very definite period of hibernation in the lower altitudes. In the Sierra Nevadas there is a more definite period of hibernation and the generations are more even. The female larvae become adults somewhat earlier in the fall. When the cold weather strikes them, development becomes very slow. In December females are fou
. Bulletin of the Department of Agriculture. Agriculture. CYPRESS BARK SCALE. 17 October and NoA^ember. These mate and die in a few days. At this time most of the females have cast their hist skin and are about one- half grown. The winter is passed as adult females, with no very definite period of hibernation in the lower altitudes. In the Sierra Nevadas there is a more definite period of hibernation and the generations are more even. The female larvae become adults somewhat earlier in the fall. When the cold weather strikes them, development becomes very slow. In December females are found containing a few eggs. These de- velop during the winter and early spring. Oviposition begins on the first warm days of spring and lasts throughout the summer, beginning about April 1 and terminating the latter part of September. In the fall the females, having com-. Fig. 3.—Seasonal history diagram of the cypress bark scale. pleted oviposition, shrivel and die. By this time the young females of the next generation are quite well developed, thus assuring the presence of adult females during the whole year. The larvae issue from the eggs 30 or 40 minutes after deposition and soon attach themselves. Larvae of the first instar may be found from April to the middle of October, second-instar larvae from the middle of May to the middle of November, and adult females from about September 15 to the following September. Male prepupse and pupae may be found in September, October, and November, and adults in October, November, and December. A male pupa was found hibernating in the Sierra Nevadas. A few scattering first and second stage larvae may be found during the winter in the milder climate near the Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original United States. Dept. of Agriculture. [Washington, D. C.
Size: 1989px × 1256px
Photo credit: © Book Worm / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookdecade1910, booksubjectagriculture, bookyear
