. Insect pests of farm, garden and orchard . is establishedon each plant. Xo aphides are found on the roots until the antsappear, and they are entirely responsible for the aphides infestingthe roots. The ants continue to care for the aphides during thesummer, carrying them to new plants when they become over-crowded or the plant dies, and so are responsible for the spreadof the pest. The first generations are entirely wingless, hxii wlunithe third generation matures a large mnubei- are winged. These 444 INSECT PESTS OF FARM, GARDEN AND ORCHARD winged females are common in late May and early Ju
. Insect pests of farm, garden and orchard . is establishedon each plant. Xo aphides are found on the roots until the antsappear, and they are entirely responsible for the aphides infestingthe roots. The ants continue to care for the aphides during thesummer, carrying them to new plants when they become over-crowded or the plant dies, and so are responsible for the spreadof the pest. The first generations are entirely wingless, hxii wlunithe third generation matures a large mnubei- are winged. These 444 INSECT PESTS OF FARM, GARDEN AND ORCHARD winged females are common in late May and early June. Theirbodies are somewhat smaller than those of the wingless forms,and appear to be shiny black, though really a deep green. Thewings expand about one-sixth inch, slightly over three times thelength of the body. They are also carried to the roots by theants, wherever they are found, and most of them deposit theiryoung on the roots. Although these winged females aid in spread-ing the pest in a bed, they probably do not migrate far unless. Fig. 318.—Strawberry root-lice which have been killed by parasites, withone of the little parasitic flies which has just emerged. carried by the wind from a l^aclly infested bed where they havebecome overcrowded. Reproduction continues, one generationfollowing another about every two weeks, during the summer andearly fall. Part of the fourth generation is winged, but the remain-ing generations are wingless. In Delaware the viviparous femalesare common on the roots until cold weather, but doubtless furthersouth they may continue to Ieproduce during the winter. Latein October and early in November the offspring develop into INSECTS INJURIOUS TO THE STRAWBERRY 445 true males and females which j)air and i-eprochicc by eggs. Theegg-laying females are very similar to the summer generationsin general appearance, though of a green color, with often ayellowish or reddish shade on the middle of the alxlomcni. Themales are much smaller and are hardly
Size: 1330px × 1879px
Photo credit: © Reading Room 2020 / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookdecade1910, bookpublishernewyo, bookyear1915
