12 BULLETIX 871, IT. S. DEPARTMENT OF AGRICULTURE. 
always indicate that there is well-developed dry-rot in the heartwood. 
In such infections it is generally possible to distinguish three stages in 
the affected heartwood, with upper and lower limits. These stages 
for convenience are termed total extent, unmerchantable extent, -and 
maximum concentration. "Total extent 75 is expressed by giving 
the height in feet in relation to the ground level of the lowest and 
highest point in the bole of the tree invaded by the fungus without 
regard to radial extent. By "unmerchantable extent" is meant the 
portion of the bole rendered valueless for lumber by the dry-rot, 
while "maximum concentration" covers that portion of the bole in 
which the decay seems to be at its worst. The upper and lower limits 
of all three of these stages may at times coincide, but especially 
that of the u rimer chant able extent and maximum concentration. It 
is self-evident that these last two mentioned can never exceed the 
total extent. 
The sporophores and shot-hole cups invariably appeared between 
the upper and lower limits of the maximum concentration. The 
lower limits varied from 3 to 25 feet below the sporophores or shot- 
hole cups, and the upper limits from 4 to 45 feet above them. In every 
case except one the lower li mi t of the unmerchantable extent was at 0. 
In other words the bole of every tree was unmerchantable, at least 
from the ground level to the sporophore or shot-hole cup. In the one 
exception the unmerchantable extent did not commence until 8.2 
feet from the ground level. This was due to the presence of a large 
open fire scar extending from to 10.8 feet. The fungus distinctly 
avoids the dried-out wood around open wounds, which habit will be 
fully discussed later in this paper. The upper limits of the unmerchant- 
able extent were variable. In the two abortive sporophores the un- 
merchantable portion extended for 10 and 24 feet, respectively, 
above the sporophores. while the extent above the shot-hole cups was 
23 and 53 feet. 
The total extent in every tree with sporophores except one (see 
above, under unmerchantable extent) reached from the sporophore or 
shot-hole cup to the ground level, but the upper extent was variable, 
being for the two sporophores 24 and 25 feet, respectively, and for the 
shot-hole cups ranging from 24 to 53 feet. 
From the figures available it is impossible to make an exact state- 
ment as to the range of the total extent, unmerchantable extent, and 
maximum concentration of the dry-rot in trees with sporophores or 
shot-hole cups, except that it may be safely assumed not only from 
the figures at hand but from observations on logging areas that the 
bole of a tree will always be unmerchantable from the ground level 
to a variable height above a sporophore or shot-hole cup. But it 
must be remembered that an old shot-hole cup indicates a greater 
development for the fungus plant in the tree than does the first 
