PLANTS AND ANIMAL PARASITES 171 



once in ten to fourteen days, until the fruit is harvested, 

 and all cocoons beneath them should be crushed. 



314. The plum curculio (306) that so often stings 

 young plums, causing them to drop before maturity, is 

 controlled by jarring the beetles, that deposit their eggs 

 in the young fruit, upon sheet-covered frames very 

 early on cool, still mornings while their muscles are 

 stiff (Fig. 78). The jarring should begin almost as 

 soon as the petals (142) fall and should be repeated 

 every still morning as long as any beetles are found. 

 Any light wood frame, 



covered with cloth, 

 may be used as a sub- 

 stitute for the more 

 convenient device 

 shown in the figure. 

 Where the substitute 



1 ,1 1 ,1 Fig. 78. — Curculio catcher. It ia wheeled 

 IS USea, tne oeetles beneath the branches of the tree, and the 

 must be looked for latter are struck with a light, cloth- 

 ,1 u f A A covered mallet, which jars the beetles up- 

 on tne Sneet ana ae- ^^ ^j^g sheet-covered frame, from which 

 stroyed as found. they roll into the box beneath. For small 

 A • 1 • trees, the trunk slips in through the slot 



Arsenical poisons ^t the left. 

 applied as soon as 



leaves appear on the trees and at frequent intervals 

 thereafter are also very beneficial in the control of this 

 pest. 



315. Destr03ring fruit. — The prompt destruction of 

 infested fruit materially aids in keeping the fruit-burrow- 

 ing insects in subjection. Hogs and sheep in the orchard 

 are most valuable assistants in this work. The apple- 

 maggot (Rhagoletis pomonella) is more effectually con- 

 trolled in this manner than by any other known method. 



316. Sucking insects include many species. They 



