[Fruit culture] . the sexual female insect in (d). The mouth parts of the sexual forms are very poorly devel-oped, and neither the male nor the female takes any mate, however, and the female lays a single large blackegg, which is usually deposited under a loose piece of barksomewhere on the lower part of the trunk of the tree. Thefemale with the large egg extruded, but still attached to herbody is shown greatly enlarged in (e). This egg hatches in the 54 APPLE PESTS AND INJURIES early spring into a wingless female like that shown in (a), thuscompleting the life cycle of the insect. T
[Fruit culture] . the sexual female insect in (d). The mouth parts of the sexual forms are very poorly devel-oped, and neither the male nor the female takes any mate, however, and the female lays a single large blackegg, which is usually deposited under a loose piece of barksomewhere on the lower part of the trunk of the tree. Thefemale with the large egg extruded, but still attached to herbody is shown greatly enlarged in (e). This egg hatches in the 54 APPLE PESTS AND INJURIES early spring into a wingless female like that shown in (a), thuscompleting the life cycle of the insect. The woolly apple aphis lives both on the limbs and on theroots of apple trees. It is most often found on young greentwigs of the trees such as water sprouts and on the leaves andin wounds. A colony of these insects is shown in Fig. 39 (a)on a twig and in a wound in the bark of a small apple these insects are found on the trunk and limbs ofa tree, they are almost sure to be on the roots also, and it is. Fig. 39 on the roots that the most damage is done. Roots of youngapple trees infested with the woolly apple aphis develop knot-like galls, and if not relieved from the sucking of the insects,the roots will eventually die. As soon as a root dies the insectsmove to a fresh root, so that the absence of the insects on a badlygalled root does not indicate that the insects have left the tree,but that they have simply moved to some other root. Thegalls, or knots, caused by the woolly apple aphis are shownin (6). 6 APPLE PESTS AND INJURIES 55 53. The insects on the twigs and fohage can be destroyedby spraying with a 7-per-cent. solution of kerosene emulsion,that is, a mixture of 1 gallon of the kerosene emtilsion andabout 13 gallons of water; with miscible oil diluted from 30to 40 times; with tobacco extract or decoction, diluted accord-ing to the directions on the package; or with a solution of1 pound of whale-oil soap and6 gallons of water. A winterspray of lime-sulphur of
Size: 1666px × 1500px
Photo credit: © The Reading Room / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookdecad, booksubjectfruitculture, bookyear1912
