. Insect pests of farm, garden and orchard . Fig. 442.—Sexual female of the woolly apple-aphis, showing egg before andafter extrusion—greatly enlarged. (After Alwood.) appear to be black, but the abdomen is really a dark yellowishor rusty brown color when closely examined, and bears more orless of the waxy secretion on the tip. Each of these winged. Fig. 443.—S(>xual female and male of the woolly apple-aphis—gi-eatly enlarged. (After Alwood.) females give birth to from four to six wingless males and females,which are deposited on the trunk of the tree. The sexes arewingless, much smaller th
. Insect pests of farm, garden and orchard . Fig. 442.—Sexual female of the woolly apple-aphis, showing egg before andafter extrusion—greatly enlarged. (After Alwood.) appear to be black, but the abdomen is really a dark yellowishor rusty brown color when closely examined, and bears more orless of the waxy secretion on the tip. Each of these winged. Fig. 443.—S(>xual female and male of the woolly apple-aphis—gi-eatly enlarged. (After Alwood.) females give birth to from four to six wingless males and females,which are deposited on the trunk of the tree. The sexes arewingless, much smaller than the summer forms, and are without INSECTS INJURIOUS TO THE APPLE AND PEAR f87 beaks, so that they take no food. The female is a Ijrown-ochrecolor, antl the male dark green or greenish-brown and smaller,as shown in Fig. 443. They become full grown in about eightdays, when they mate and the female then lays a single large blackegg, which is deposited in the crevices of the bark on the lowerpart of the trunk. These eggs hatch in the spring and give riseto new colonics. As they multiply large galls are produced on the roots, thetissue probably being poisoned by the mouth-parts of theinsects. As a result the roots soon die and the aphides thenmigrate to the growing roots, so that their absence on the worstknotted roots does not indicate th
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Keywords: ., bookcentury1900, bookdecade1910, bookpublishernewyo, bookyear1915
