176 



Bulletin 252. 



of the plant parasite ; by poisoning the leaf-eating insect, or killing the 

 sucking insect with something which destroys its body, in the case of 

 insects. 



Cornell spray calendars have stated that spraying is a type of 

 orchard insurance. Growers ask: Shall I spray when I have little or 

 no fruit ? The answer is : Yes, by all means. Insure for your trees 

 a crop of healthy leaves, so that wood may be grown and fruit buds 

 developed. This is the best way to secure a crop the following year. 

 The man who sprays year in and year out insures his crop against standard 



enemies, and to a large de- 

 gree against epidemics, and 

 tends to lessen the numbers 

 of his staple insect foes. 



Hoiu to Spray. 



First, know the enemy. 



Study the crops you are 



growing, and you will learn 



to recognize the parasites 



that attack them. Learn 



the feeding habits of these 



and the principal facts of 



their life-history. Then 



study tlie remedy, under- 



^. ^, , , , , ^, . . stand its principles — how 



Fig. IJ5. Slugs of the potato hecilc. Chemmg insects. . xt 



It acts. JNext, secure the 



appliance which seems best adapted to your needs. Prepare your spray 

 mixture carefully, and apply it thoroughly. Next to timeliness, thor- 

 oughness is of prime importance. Hundreds of fruit-growers and farmers 

 waste time, energy and material by indiscriminate and hasty squirting 

 of spray mixtures over fruit trees and farm crops. Remember that the 

 principle is protection, and that the plant is protected only when it is 

 completely covered. Some insects must be hit to be killed. Do not 

 spray, therefore, unless you do the work thoroughly for you will disgust 

 yourself and destroy your neighbor's faith in the treatment. Spraying 

 is not pleasant work but fruit-growers and farmers must accept the situation 

 and make the best of it. 



In the succeeding pages of this bulletin, the subjects of formulas, 

 machinery, insects and diseases are treated. Each division has been 



