46 MANUAL OF FRUIT DISEASES 



so far as the market value is concerned. In Xew England con- 

 siderable damage is done in storage. In Kentucky, Indiana, 

 Missouri, Illinois, Alabama and Massachusetts the fruit is 

 often seriously affected in the orchard. In Massachusetts 

 80 to 90 per cent of the apple-rots are of this kind, while in the 

 other states just referred to black-rot is, next to bitter-rot, the 

 most common type of apple fruit-decay encountered in the 

 orchard. 



The losses incurred through leaf-infections depend on the 

 extent of the infection, that is, the size and number of spots on 

 each leaf. In New York, only mild cases occur and the injury 

 is not appreciable. In New Hampshire, Virginia and the Ozark 

 region defoliation often results from the attacks of this leaf-spot 

 pathogene. The Ben Davis, Black Twig, Chenango, Baldwin, 

 Rhode Island and Twenty Ounce are most susceptible to leaf- 

 spot. 



The damage done to limbs is rarely appreciated. The largest 

 limbs of mature trees are most subject to this disease, and while 

 to most orchardists the loss of these limbs seems momentous, 

 a great many are inclined to forget the cost of growing such 

 limbs to bearing age as well as the expense of treating the same 

 when thus diseased. Whole trees are sometimes killed. A 

 case is on record where the trees on thirty acres of an eighty- 

 acre orchard were ruined, and those on the remaining fifty 

 acres were rendered almost worthless. The dollar loss in- 

 curred by the black-rot canker would be difficult to estimate. 

 However, reckoning the amount of fruit lost as a direct result of 

 canker on bearing limbs is a simpler matter, and for New York 

 State the figures representing the annual loss through this 

 channel have been conservatively put at $750,000. In those 

 apple-orchards bordering Lake Ontario, the Twenty Ounce 

 variety is by far the most susceptible. But it is difficult to 

 point to a variety which in general is second in this respect. 

 The Esopus, Baldwin, Wagener, Rhode Island and Tompkins 



