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INSECTS INJURIOUS TO THE APPLE 



This insect eats foliage of apple, plum, fruit trees, and several of 

 the forest trees. 



Control. Gather and destroy egg-clusters in winter. The 

 larvae are easily kept in check by poison sprays, preferably arsenate 

 of lead. Spray with this compound as for the codling moth. 



The Apple Leaf Aphis (Aphis mali Fab.). This is a serious 

 pest, particularly on young trees. The leaves, when attacked, 

 curl up and may drop off. 



Description and Life History. The black winter eggs of these 

 lice are frequently seen on the axils of the buds in late fall and win- 

 ter. These eggs hatch in early spring, each egg producing what is 



FIQ. 104. Forest tent caterpillar: a, egg mass (compare with egg mass of American 

 tent caterpillar) ; 6, moth, enlarged; c, top of enlarged egg; d, side view of three enlarged eggs. 

 (After Riley.) 



known as the " stem-mother," dark green in color. These stem- 

 mothers work into the folds of the opening leaves, insert their 

 beaks into the tissues, and feed upon the sap. In favorable weather 

 they become adult in about two weeks and give birth to living 

 young at the rate of from three to twelve a day for about three 

 weeks, each stem-mother producing from 75 to 100 individuals. 

 These first insects are always wingless females. The fol- 

 lowing generations during the summer are all viviparous females. 

 The second generation is slightly larger than the first. A small 

 percentage of individuals of this generation are winged. Many 

 of the third generation are winged, scattering to nearby trees to 

 start new colonies. The wingless forms are larger and somewhat 



