308 State Horticultural Society. 



It is somewhat difficult to study the cause of this disease, due to 

 the fact that the trouble is all beneath the soil. As yet, nothing definite 

 has been discovered in regard to it. Dr. Smith thinks that it is due 

 to some external parasite, while Halstcd suggests a fungus origin. 



Trees affected by this disease at transplanting age, seldom, if ever, 

 come to successful fruiting, and by far the greater number of them 

 may be expected to die before they have attained bearing size and age. 



So far, all experiments to cure the disease have failed. Favorable 

 results from injecting Bordeaux mixture into the galls have been re- 

 ported in California, but practical measures must be chiefly preventive, 

 and the most important of these will be the rejection of affected 

 nursery stock. 



PEACH ROT. 



While the fungus diseases of the peach do not rank with those of 

 the plum in destructiveness, several of them are quite damaging. The 

 belief that peaches rot solely because of the w^eather is often ex- 

 pressed ; but while, to be sure, the weather influences the amount of 

 rot, it is only a condition and not a cause of peach rot. This is truly a 

 fungus disease, due to the rot fungus (MonUia fnisfigciia Pcrs.) 

 The weather simpl}^ influences the amount of rot by offering favorable 

 or unfavorable conditions of heat and moisture. This rot fungus, as 

 most fungi, has its growth favored by warm weather and abundant 

 moisture, so that if these conditions come together near ripening time, 

 we may expect serious loss of fruit. It is no unusual thing to see a 

 large number of brown rotten peaches on the trees, with a great abun- 

 dance of ash-colored spores produced upon the surfaces. These pow- 

 dery masses of spores are easily scattered by the wind and rain and 

 will cause any amount of mischief where they find a suitable place. 

 Favorable places are numerous, such as in a dense cluster of fruit, or 

 where the fruit is densely shaded by leaves ; and, in case of warm, 

 showery weather at times of blossoming, the spores may enter through 

 the blossoms and cause serious damage in the form of twig blight. It 

 may be a matter of surprise to some to hear that this rot fungus de- 

 stroys the twigs and blossoms as \vell as the fruit. We are accus- 

 tomed to see much rot among the early varieties, like Hale, Alexander 

 and others, and are consequently apt to call these susceptible varie- 

 ties. However, a large amount of rot m any variety may be expected 

 during warm, \vct weather at ripening time, and there seems no rea- 

 son to regard early varieties, on the whole, as more susceptible than 

 late varieties. 



