FUNGI PRODUCING HEART-ROT OF APPLE 
TREES 
B. O. Dodge 
(With Plates 173-176, Containing 10 Figures) 
Any one familiar with the old apple orchards of the East is 
aware that there must be specific causes connected with the rot- 
ting of the trunks of the trees. When trees that ought to be in 
the prime of life are found with huge knot-holes leading into 
great hollows in the trunk, the pathologist feels perfectly certain 
that some fungus has gained entrance to the wound caused by 
the removal of a limb at this point. 
At Camp Columbia, near Litchfield, Conn., and on the farms 
in the vicinity, there are many old orchards that are especially 
favorable for a study of diseases peculiar to the apple tree. Na- 
ture is left to take its course in the abandoned orchard, with the 
result that fungi directly or indirectly the cause of wood-rot are 
given an opportunity to develop their fruiting bodies, without 
which the identification of the disease is still more uncertain. 
Some of these trees seventy-five or one hundred years old are still 
bearing apples, although the trunk is a mere shell of sap-wood, 
frequently only a part of the shell remaining. A large percentage 
of the trees bear evidence of the presence of fungi commonly 
known as heart-rots. 
I have made an effort to collect various types of fungi growing 
on living trees with the hope that something further might be 
contributed toward the discovery of the particular fungi causing 
these destructive heart-rots. I was greatly assisted in this work 
of collecting and photographing the specimens by Mr. Paddock, 
a student in botany at the camp. 
The well-known rots of hickory, oak, maple, elm, etc., were 
fairly common there. A number of bracket and encrusting forms 
(Polyporiis versicolor, SchisopJiylhim commune, Irpcx lacteus, 
etc.) were found on dead limbs and trunks of the apple, but as 
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