PLANT DISEASES IN I908. IJ 



conclusions from them would be fallacious. However, taken in 

 connection with common ex]3erience it seems safe to say that it 

 would be a matter of considerable hazard to invest much money 

 in attempting to grow any but the most hardy varieties of apples 

 in those portions of the State where the lowest winter tempera- 

 ture frequently reaches or approximately reaches -30° F. 

 Again it may be said that the grower who confines himself to 

 Baldwins, and possibly Ben Davis, except in the mildest parts 

 of the State, e. g., where the minimum winter temperature, 

 repeated at frequent intervals, seldom reaches below -20° F., 

 or at the utmost -25° F., must expect greater losses than his 

 neighbor who plants most any of the other commercial varie- 

 ties grown in Maine. , 



It is admitted that other states farther south frequently suffer 

 nearly as much from winter killing of apples but it should also 

 be remembered that this is probably due to frequent and abrupt 

 changes from severe cold to mild weather, these changes being 

 more common than is the case with the climate of Maine. 



Crotch Injury of Apple Trees, Caused by Weather 

 Conditions. 



In the spring of 1907 the writer was called to Dover, Maine, 

 to examine an orchard of about 1200-1500 trees from 8 to 12 

 years old. On the lower portions of this orchard many of the 

 trees were plainly winter-killed, including 5 to 10 per cent of 

 the whole orchard. Quite frequently trees could be found with 

 "frost patches" or portions of the bark killed and loose on the 

 more exposed parts of the larger limbs and trunk, but the most 

 characteristic thing about this orchard was the constant occur- 

 rence of the crotch injury illustrated by Fig. 2. This 

 occurred to a greater or less degree on probably 75 per cent 

 of the trees in the orchard, the varieties being largely Ben Davis, 

 and Stark. The bark showed ever}^ appearance of recent death, 

 with no invasion of fungi, neither were there any scars, cankers, 

 or other evidence of past injuries of this kintl. The dead bark 

 was drying down and cracking away from the healthy portion — 

 it was too early in the season to see evidences of attempts to 

 heal the wounds. The owner, an intelligent and careful 



