WESTERN YELLOW PINE IN OREGON. 17 
Since yellow-pine forests are grazed over by sheep and cattle, the 
reproduction is somewhat exposed to damage by these animals, par- 
ticularly by sheep, which trample a good many seedlings when close 
herded. Sheep also, when short of forage, as along driveways or 
near bed grounds, browse on them in such a way as to deform the 
seedlings permanently. If the range is not overstocked and the sheep 
are properly handled, they will not, in Oregon, do any appreciable 
damage to the yellow-pine young growth in the forest at large ; trees 
over 6 feet high are practically immune from damage. 
In some parts of the State, particularly in Klamath County, are 
found here and there large trees upon which are great scars, from 3 to 
7 feet above the ground, half encircling the tree. (See PL III.) These 
scars were caused years ago by Indians who, in the springtime, stripped 
the bark in order to get at the mucilaginous layer of forming wood, 
which they scraped off and used as food. 1 The scars make the trees 
vulnerable to light surface fires and detract considerably from their 
merchantable value. 
CHARACTER OF THE STANDS. 
Yellow pine is fundamentally a gregarious tree; that is, it is a tree 
which does best and is found most commonly in pure or nearly pure 
stands. Most of the forests of Oregon in which it occurs commercially 
are at least 75 per cent yellow pine, and the other trees that are pres- 
ent in the mixture are apt to grow in groups by themselves and not 
in intimate mixture with the pine. One reason why yellow pine 
occurs so largely in pure stands is that it will grow and form fine 
forests in situations on the plateaus and south slopes that are too dry 
and hot for other species, and being a rather unsuccessful competitor 
of the more tolerant species, Douglas fir, white fir, and lodgepole 
pine, it is largely excluded from soils moist enough for these species 
to thrive in. It does occur, however, in mixture with other species 
in almost every degree. 
In most of the pure yellow-pine forests of the State the trees are 
spaced rather widely, the ground is fairly free from underbrush and 
debris, and travel through them on foot or horseback is interrupted 
only by occasional patches of saplings and fallen trees. (See PL IV.) 
The forests are usually not solid and continuous for great distances, 
except along the eastern base of the Cascades, but are broken by 
treeless " scab-rock ridges," or natural meadows. On the north 
slopes, in draws, or in other places where mixed with other species, 
the yellow-pine forests are usually denser, more brushy, and therefore 
harder to traverse. Toward the limits of the forests adjoining the 
desert the stand is confined usually to a fringe of trees along the 
» Sargent's Silva, XI, p. 82. 
54891°— Bull. 418—17 3 
