300 Report or THE BoTraNnicaAL DEPARTMENT OF THE 
unusually warm, moist late-ssummer and fall, resulted in 
much and very late growth of apple trees in both sod and 
cultivated orchards. No light frosts occurred to check growth 
and ripen the wood till the cold wave of October 10-12, with 
a minimum of 18° F., killed many trees to the ground or 
snow line and produced dead, brown areas on the bark of 
others, especially in orchards where the trees had been set less 
than five years. Though some injured or dead trees could 
be located in February, many severely affected ones showed no 
evidence of injury till midsummer, when their foilage became 
discolored, followed in many cases by death in late summer. 
On various parts of the most exposed sides of trunks, sunken, 
brown, canker-like areas appeared. But the injury could gen- 
erally be noticed first by the presence of a brown inner-bark. 
At times, when the surrounding bark had grown sufficiently 
in thickness, a more or less definite crevice appeared, sepa- 
rating the living and dead bark. 
In several orchards cited 80-100 per ct. of the young Baldwin 
trees were either killed or severely injured and Rome Beauty 
fared but little better, while Ben Davis, Gano, Northern Spy, 
Jonathan and perhaps Grimes proved more resistant. It is 
suggested that the hardiness of a variety depends upon its 
relative earliness of growth and ripening of its wood, and 
that susceptible varieties which are very desirable, be top- 
grafted on resistant sorts. | 
The indirect effects of the severe winter-injuries of 1906-07, 
it is thought, would be noticeable for several years, since dead 
areas in the bark hinder “sap flow” and afford entrance for 
wound fungi which may rot the trunk or roots. 
As may be expected, winter-injury to fruit trees has also 
been recorded in Maine, though for obvious reasons mostly to 
trunks and branches. W. J. Morse?’ says that in an orchard 
survey, after the very severe winter of 1906-07, it is shown 
that 11 per ct. of the trees in 950 orchards were either killed 
or injured. Baldwin and Ben Davis seemed most susceptible; 
* Maine Agrl. Expt. Sta. Bul. 164, pp. 12-21. 1907. 
