78 WILSON & TOOMRR FERTILIZER COMPANY 



entirely upon so coating the surface of nninfected vege- 

 tation with Bordeaux mixture or other fungicides that 

 when the spores fall upon it the} 7 are killed. This ex- 

 plains the need of thorough spraying. Unsprayed por- 

 tions are as readily affected as though the rest of the 

 plant were also unprotected. As long as new leaves are 

 forming it is necessary to spray every ten days or two 

 weeks until the disease is eradicated, even when the most 

 favorable conditions prevail. Dry, sunny weather is 

 against fungous growth, while cloudy, wet weather favors 

 it. Hence, during cloudy days diseases spread more rap- 

 idly. If Bordeaux mixture has time to dry thoroughly 

 before the rain falls it will be quite resistant to washing 

 effects. This is true of other sprays to a great extent, 

 but even if the fungicide used is washed off, it has killed 

 myriads of spores which would have infected new areas. 

 Spraying must not be delayed because of rainy weather. 

 There are four distinctions for the grower to make 

 when considering fungi, these being based upon the hosts 

 necessary for their establishment. The class I have men- 

 tioned attack living vegetable tissue and are our "ene- 

 mies," in that they work against us, but there are also 

 "friendly" fungi, so called because they live only on 

 animal tissue and by becoming established upon and 

 killing our insect enemies, scale, whitefly, etc., they work 

 to our advantage. Another kind of "noxious" fungi 

 exists in our groves and gardens which can live upon 

 dead and decaying matter, but when such matter is a 

 weak or dead part of a live host the toxine, that is, the 



