No. 7. DEPARTMENT OF AGRICULTURE. 225 



these last may be occasionally omitted ; but spraying is an absolute 

 necessity, for what availeth it if you raise a large crop and lose 

 it through a worm hole. 



In this talk, I will not enter into details as to the great value of 

 spraying; we are past that stage. There are few that do not believe 

 in the value of the copper salts, or the compounds of sulphur as 

 fungicides, or the arsenates as insecticides and the emulsions for 

 sucking insects. There are many who do not spray, but the prac- 

 tice is giving such good results that there is an annual increase in 

 the number of those who thoroughly spray their trees. So it is 

 no longer a question as to whether it is good, but how, when and with 

 what to do it. Sometimes we hear of unsatisfactory results, but 

 it is not the fault of the system, but the improper preparation or 

 application of the same. One must familiarize himself with the 

 nature and habits of the organisms he wishes to destroy. To per- 

 form an operation intelligently you must thoroughly understand 

 the reason why you do it, otherwise success is merely accidental. 

 You need not necessarily know all the diseases by name or the 

 life history of every insect, but the more you do know about their 

 origin, their methods of propagation, where they pass the winter, 

 whether in the egg, larva, pupa or in the perfect form, when they 

 appear in the spring, how they affect the tree, plant or fruit, whether 

 by eating or by sucking, the more you know of these facts the better 

 you will be prepared to attack them in their most vulnerable form. 



Most of the fungi are internal parasites, they must be attacked 

 in the spore stage. Spraying for fungi is more largely a preven- 

 tive than a curative measure. Spraying for insects and fungi is 

 a form of insurance whereby the grower may secure larger crops, 

 of finer, brighter and firmer fruit, possessed of higher quality than 

 could otherwise be obtained. By spraying, the benefits are plainly 

 seen by the increased health of the tree or plant, the foliage being 

 thicker, richer in color, and free from fungi, thus enabling them 

 to perform their functions of preparing plant food. Should a tree 

 from any cause become defoliated, it loses its power of assimilation 

 and preparing the food for the tree bud and fruit. It carries its 

 influence farther, preventing the premature dropping of the fruit. 



Spraying is, to a certain extent, cumulative, its benefits are not 

 all seen the same year of application. This would of course not 

 hold good with plants that grow their stock, develop their buds 

 and mature their fruit the same season, such as the annuals. But 

 with all trees that form their buds the previous season, such as the 

 apple, peach, etc. Spraying is not a panacea for all the causes of 

 failure with fruit raising. It will not take the place of pruning, 

 fertilizing, or cultivation. An orchard that is unproductive from 

 neglect, lack of tillage or worn out soil, cannot be made produc- 

 tive by spraying alone, but it is one of the essentials. 



Thoroughness 



There are many failures from lack of thoroughness. A tree or 

 plant need not be sprayed until it drips from the foliage and runs 

 down the limbs and trunk, but every part should be thoroughly 

 moistened. Another cause of failure, is the use of the wrong ma- 

 terial, a fungicide is often used for insects, and an insecticide is 



15—7—1910 



