A STUDY OF HEART-ROT IN WESTERN HEMLOCK. lah 
can not be used to express this relation, since it varies with all the 
factors influencing the progress of the decay. As a rule, it would 
be safe to add to the linear estimate of the cull 14 feet beyond the last 
recognizable punky area or area showing the slightest yellowish dis- 
coloration. The typical rot (figs. 4, 8, and 9) is readily recognizable 
and has a characteristic reddish brown to brownish yellow color, 
often spotted with areas of a more vivid rust color and occasionally 
showing streaks or lines of a dark red to reddish brown hue. Its 
texture is very pronounced and this, combined with its color, forms 
the basis for the scaler’s common name for the defect ‘‘stringy 
brown-rot.” In the last stages of decay the heartwood is entirely 
disorganized, giving place to large cavities in the butt logs and some- 
times in the logs above. The stringy nature of the rot can be readily 
seen in this stage and also in the ends of logs badly but not hollow 
Fig. 8.—Longitudinal section of an old sporophore of Echinodontium tinctorium on hemlock, showing its 
y relation to branch stubs. 
rotted, especially in the grass-stubble effect (figs. 4 and 10) produced 
by the sawing. The brick-red color of the sporophores is often found 
distributed through the typical rot and in the branch stubs in the 
final stages of decay. 
AREAS STUDIED AND FIELD METHODS USED. 
The areas selected for study lie in the drainage basin of the Priest 
River in Idaho. Throughout this region western hemlock is rather 
evenly distributed, extending downward from the subalpine zone 
into the upper limits of the yellow-pine zone. The species attains 
its best development on damp north slopes and is found greatly 
suppressed when growing as an understory in the dense bottom 
stands. 7 
One of the factors promoting the development of forest-tree fungi 
of the region is the high annual precipitation. The dry periods of 
