APPLE DISEASES 37 
found at any place on any or all sides. Injuries may occur at 
any height on a tree; at the crown, the injury known as crown- 
rot or collar-rot; at the crotch, crotch-injury; on the main 
limbs as they diverge from the crotch, known as sun-scald; 
at the roots, root-injury. The tips of branches are sometimes 
killed back for some distance. Not infrequently the injury 
may extend from 
the collar to the 
head, involving 
large areas. 
Crown-rot, or 
collar-rot, occurs at 
the crown or base 
of the trunk at the 
ground line. It is 
distinguished from 
sun-scald and 
crotch-injury by its 
position on the tree. 
It is normally an 
early form of win- 
ter-injury. Obser- 
vations indicate 
that it may occur 
from October to ~ 
December in the Fic. 8. — se sss SRS ar ACO a result of low 
latitude of New 
York, Ohio and Connecticut. The Tompkins King, Grimes 
and Hubbardston are most subject to crown-rot. In such 
injured places the bark appears discolored, dead and loosened 
from the trunk, sometimes split open, exposing the wood. 
Again the injured bark clings to the wood for a time, forming a 
canker at the crown. 
Sun-scald is usually made evident in the late spring by the 
