. Annual report. Entomological Society of Ontario; Insect pests; Insects. 32 REPORT OF THE ENTOMOLOGICAL. 0 6 12 18 24 30 36 4 2 4 8 5 4 60 66 72 78 84 90 96 POPULATION PER SQ. FT. Fig. 1. Fluctuations in sweetclover weevil populations at Brandon, Man., 1945-49 (larval population and new generation, 1947, estimated). Variations in Seasonal History The life-history, according to Bird (1), is as follows. Winter is passed in a sexually immature adult state. In the spring the weevils come out of hibernation, feed, mate, and lay eggs on the soil surface. The larvae move down to the roots of sweet c
. Annual report. Entomological Society of Ontario; Insect pests; Insects. 32 REPORT OF THE ENTOMOLOGICAL. 0 6 12 18 24 30 36 4 2 4 8 5 4 60 66 72 78 84 90 96 POPULATION PER SQ. FT. Fig. 1. Fluctuations in sweetclover weevil populations at Brandon, Man., 1945-49 (larval population and new generation, 1947, estimated). Variations in Seasonal History The life-history, according to Bird (1), is as follows. Winter is passed in a sexually immature adult state. In the spring the weevils come out of hibernation, feed, mate, and lay eggs on the soil surface. The larvae move down to the roots of sweet clover, where they feed on the root hairs and nodules. They mature in July and emerge as adults in late July or early August. After a feeding period, they go into hibernation in the surface debris and soil when the first frosts occur. Five years' study has shown considerable variations in the seasonal history. These are best illustrated in Table I. The earliest emergence from hibernation occurred from April 11 to May 5. Dispersal flights took place in April, May, and June and. 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 Entomological Society of Ontario; Ontario. Dept. of Agriculture. Toronto, The Society
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Keywords: ., bookcentury1800, bookdecade1870, booksubjectinsects, bookyear1872
