Dodge: Heart-Rot of Apple Trees 
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polypore {PI. 174, f. i) three or four inches in diameter, de- 
pressed or funnel-shaped and somewhat inequilateral. The sur- 
face is radially split or cracked and somewhat lobed, and is also 
broken up into concentrically arranged scale-like tufts. The tubes 
are large and angular, running down on the stem, which is very 
well marked. This plant is tough from the first, about the con- 
sistency of the railroad tie fungus {Lentinus lepideus). It was 
kept under observation for about three weeks. At the time the 
photograph shown in PL 174, f. i, was taken, Mr. Paddock called 
my attention to the spores that were being shed in little white 
clouds. It is possible that this is a form of Polyporus admirabilis 
that grows saprophytically on wood other than that of the apple 
tree. The character of the surface, the large size of the angular 
pores, and its place of growth, suggest more strongly, however, 
that it is quite another species. Dr. Murrill, who has examined 
this specimen, informs me that it is near P. Underwoodii, although 
it does not have a black stem as do both the specimens at Albany 
and as required by the description. 
The apple grower is much more interested in the extent of 
damage that is being wrought than in controversies over the iden- 
tity of the fungus causing the disease. He wants to know how 
to recognize the fungus, how to cure the diseased tree, and how 
to prevent further infection. While it is the part of wisdom to 
follow the most approved methods of pruning, it may be well to 
consider whether the ordinary precautions that are taken to coat 
the cut surface with paint is really of much avail in keeping out 
the spores of these fungi. Freezing and thawing, wetting and 
drying certainly will cause cracks to open up and, unless the sur- 
face is kept well painted until a callus completely covers the 
wound, there can be no certainty that some fungus will not gain 
entrance. The fungus here_ under consideration causing the 
heart-rot of apple trees could, perhaps, be more easily controlled 
by the destruction of the spore-producing bodies themselves, since 
they are large and conspicuous and easily removable. 
Other Types of Punks Causing Heart-rot of Apple Trees 
As I have noted previously, P. admirabilis belongs to the group 
in which the fruit-body has a stem, although it may be very much 
