302 SCHOOL ENTOMOLOGY 



and drop to the sheet, and may be dropped in a can of water 

 and kerosene. 



Chief dependence for control, however, is now placed on 

 spraying with arsenate of lead, two pounds to fifty gallons. 

 On apples the usual sprayings for the codling moth will give 

 all the benefit possible. On peaches the first spraying should 

 be given about ten days after the blossoms fall, and a second 

 spraying two weeks later, the arsenate of lead being added to 

 self-boiled lime-sulphur mixture applied for controlling the 

 rot and similar diseases. Practically the same applications 

 as for peaches will probably be found satisfactory for plums 

 and cherries. Only neutral arsenate of lead, i.e., that having 

 little or no soluble arsenic, should be used on stone fruits, as 

 a slight amount of soluble arsenious acid will burn the foliage 

 badly. 



Orchards near woodlands are always more badly injured, 

 and where weeds, grass, and trash are abundant the beetles 

 find more suitable quarters for hibernating and are more 

 abundant. Cleaning up the orchard and its surroundings is, 

 therefore, important for this and other insect pests. 



159. Leaf Aphides.* Nearly every plant is attacked by 

 some species of aphis and fruit trees are no exception. The 

 rapidity with which these little plant-lice multiply has 

 already been explained (page 270), and is the reason they 

 often become so destructive. Insignificant individually, they 

 will reproduce so rapidly that in a week or two the leaves are 

 covered with them and the growth of the tree is seriously 

 checked. The more common species may be recognized 

 by their coloration and habits, and though they differ some- 

 what in their life histories, most of them are controlled by 

 the same general methods. 



Three or four species are common upon the apple. 

 * Family Aphididce, see page 66. 



