-22- 

 Spraying . 



An old orchard which has been neglected for many years 

 is a source of infection, a breedin;; place for all the dis- 

 eases to which the apple is heir. The environment has been 

 such that the trees have been weakened and made susceptible 

 to disease. Some of the things which aid disease in the 

 orchard are: poor drainage, heavy, v/et soil, poor cultiva- 

 tion and weeds which protect many dieoases and pests during 

 the winter. The owner of one of these orchards has a two- 

 fold task on his hands. He must drive out the disease pro- 

 ducing insScts and fungi and after they are out he must keep 

 them out by spraying. 



In order to successfully combat a disease one should 

 know something of its nature; how and when it attacks the 

 tree. This is essential in order that the spraying may be 

 done at exactly the correct time and the correct kind of 

 poison used for the trouble. One disease requires one kind 

 of spray and another disease requires another. There is 

 no good in spraying with the wrong remedy. Some of the raore 

 important insect and fungous diseases I will describe to- 

 gether with control methods for the same, 



Apple Scab . The apple scab, caused by Venturia ina e - 

 (j^ualis, is one of the most destractive fungous diseases of 

 the apple and is found every where the apple is cultivated 

 and the weather conditions are favorable. 



On the leaves scab may be found as irregular rounded 

 spots, somewhat swollen and with an indefinite margin, be- 

 coming brown as they grow older. The spots may be as large 



