176 Principles of Plant Culture. 



of established value. The application to the young 

 foliage of powerful odorants, as coal-tar water or a 

 solution of carbolic acid, may prove beneficial. 



313. The Codling-Moth,* which causes so-called 

 "wormy" apples and pears, is controlled by spraying 

 the trees at the time of egg deposit, with water contain- 

 ing Paris green (284). The first spraying should be 

 given as soon as the petals (142) fall, to be followed 

 by a second six to ten days later. If much rain falls 

 at this season, the sprayings may need frequent repeti- 

 tion. A drop of poisoned water should be lodged in 

 the calyx (141) of every fruit, and as this evaporates, 

 the poison deposited on the skin kills the newly-hatched 

 insect as it eats its way inward. 



A band of cloth or paper, placed about the trunk of 

 fruiting apple or pear trees forms a convenient retreat 

 for larvas of the codling-moth, in which to pupate. 

 They may then be readily destroyed by removing the 

 band. The bands should be a few inches wide, and 

 should be put on before midsummer. They should be 

 taken off 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. 76). 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. 



* Carpocapsa pomonella. 



