46 MANUAL OF FRUIT DISEASES 
so far as the market value is concerned. In New 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 limks 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 
