WESTERN YELLOW PINE IN OREGON. 11 
ing it off at the base with a smoldering flame. An examination of a 
great many burns in eastern Oregon shows that an average surface 
fire, on land which has been periodically burned over before, kills in 
this way one merchantable tree on from 1 to 4 acres. The aver- 
age number on 130 sample acres examined in detail was one tree 
to every 1.12 acres. This is not a large number of trees, and they are 
so scattered about in a burn as. not to be conspicuous; but in the 
aggregate it is an enormous loss, especially as each of the repeated 
fires may kill the same number, and the trees felled by these surface 
fires are usually the larger ones. 
(3) The " pitching" of the butts of commercial trees. 
Trees that are fire-scarred or which have been excessively heated 
about their bases are very apt to become " pitch-butted ; " i. e., a great 
deal of "fat" pitch is deposited in the wood in the lower part of the 
stem. This pitch greatly lessens the value of the log for lumber 
because excessive pitch is a defect which bars lumber from the best 
grades on the market. A tally of 1,184 butt logs in the Blue Moun- 
tains shows that 25 per cent of them are " pitched" and that the aver- 
age diameter of the pitchy area on the basal cross section of the log 
is 14.7 inches. This indirect result of surface fires is not conspicuous, 
but is a very real source of loss. 
(4) The impoverishment of the soil by repeated burnings. 
Frequent fires consume the vegetable matter, which should be 
allowed to accumulate and decay and thereby better the physical 
condition and add to the fertility of the soil. 
(5) Destruction of the reproduction which should form the basis 
for the next crop. 
Each fire kills the seedlings and some of the saplings, so that, if 
the fires are of frequent occurrence, no young growth has a chance to 
replace the mature trees that die from natural causes. Yellow pine 
normally occurs in Oregon in uneven-aged stands in which trees of 
all ages are in intimate mixture ; frequent fires prevent the stand from 
having the proper number of young trees. If this process is con- 
tinued long enough, it will annihilate the yellow pine by gradually 
killing off the old trees and at the same time preventing the survival 
and maturity of any young ones. This very thing has happened in 
places in the Siskiyou Mountains and southern Cascades. Here 
areas once covered by fine stands of yellow-pine timber are now tree- 
less wastes, covered only by brush or mock chaparral. 
(6) Degeneration in the forest type. 
In certain parts of the State repeated surface fires have the effect 
of transforming the forest type from a stand consisting largely of 
yellow pine to one consisting of lodgepole pine, whose reproduction is 
extremely abundant and vigorous after fire., 
