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than on those on main branches. The practice of thinning 

 fruit to keep the yield regular tends to reduce the disease, but 

 in cases of severe thinning to produce very large fruit, the 

 disease is likely to occur in great severity. Bitter-pit may 

 occur in the best-managed orchards, and probably few varieties 

 are immune. 



Spongy Drt-Rot. 



But little importance attaches to this disease in the orchard, 

 but in storage it may sometimes cause considerable loss. We 

 have never observed it on fruit still clinging to the tree except 

 where a branch had bent down and the fruit rested on the 

 grass or ground beneath. It is, however, commonly found on 

 windfalls beneath the tree, and it is likely that the causal 

 fungus, Volutella fructi, is normally a wound parasite. 



In storage, the trouble spreads through contact, but is held 

 in check by low temperatures. Avoidance of bruised or scarred 

 fruit will do much toward keeping this rot out of the storage 

 package. The appearance of Volutella-rot is somewhat like 

 that of black-rot, for which it is often mistaken in storage. 

 The rotted area is, however, more sunken and the decayed 

 tissue is dry and spongy. The surface of the spot is black, 

 and the skin becomes roughened when the fruiting bodies of 

 the fungus, which are more closely clustered than in black- 

 rot, break through it. 



Apple Eust. 



Apple rust is important in Massachusetts, as a rule, only to 

 the growers of Wealthy and Jonathan. Other varieties com- 

 monly grown in the State are little affected by it. In the 

 middle Atlantic States, the York Imperial is very susceptible.. 

 Rust is much more destructive on quince than on apple in 

 this State. 



Apple rust is caused by a fungus, Gymnosporangium, which 

 not only lives on two radically different hosts — the apple and 

 the red cedar — but is absolutely dependent on both of these 

 hosts for the completion of its life cycle, and, in fact, for 

 reproduction and dissemination. 



In regions where red cedars abound the galls or "cedar 

 apples," which are the winter stage of this disease produced 



