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NITED STATES DEPARTMENT OF AGRICULTURE 
Washington, D. C. December, 1924 
THE ROLE OF. FIRE IN THE CALIFORNIA PINE FORESTS ! 
By 8S. B. Snow, Silviculturist, and EH. I. Kotox, National Forest Inspector, 
Forest Service 
INTRODUCTION 
In forest regions where fire commonly results in complete destruc- 
tion of the standing timber the role played by fire is definitely recog- 
nized and serious efforts are made to control this menace. 
In the California pine region, however, and in other localities where 
fires run through the forest comparatively lightly and only occasion- 
ally assume the dimensions of a crown fire, injury is less obvious 
and the consequences of fire both in mature and in growing timber 
often go unrecognized. 
Physical conditions in the pine forests of California have led to 
the frequent recurrence of fires for centuries, but the fact that mag- 
nificent forests still cover large areas and give the See of well- 
stocked, vigorous stands has blinded the public to the harm that fires 
have done and are steadily working throughout the whole region. 
Were it possible for the observer to visualize the entire area upon 
which pine has grown, and to behold it truly fully stocked, he would 
then see by comparison that the present California pine forests rep- 
resent broken, patchy, understocked stands, worn down by the 
attrition of repeated light fires. 
The true role fire has played in this region can be appreciated 
to-day only by careful scrutiny of the less obvious forms of dam- 
age. True, the thousands of acres of waste land or unproductive 
brush fields, the small stands of mature timber so isolated by brush 
_as to be inaccessible for logging, the areas on which the forest type 
is changing to less valuable species, the failure of cut-over lands to 
reproduce—all these are apparent enough, and tell an eloquent tale 
1 The pine region of Californiaincludes the timbered parts ofthe Sierras, the timbered parts of the north- 
ern. Coast Ranges that are away from the influence of the Pacific Ocean, and the timbered parts of the 
mountains of southern California. Itincludes the yellow-pine type, of which western yellow pine (Pinus 
ponderosa) is the principal tree, and the yellow pine-sugar pine type,in which western yellow pine grows 
in mixture with sugar pine ( P.lambertiana) andin which Douglas fir (Pseudotsuga tarifolia) , incense cedar 
(Libocedrus decurrens), and white fir ( Abies concolor) occur as associate treesin varying proportions. This 
typeis often called the mixed conifer type. The pine region alsoincludes the sugar pine-fir type where 
thetwo firs (A. concolor and A. magnifica) growin mixture with the sugar pine. Insome places the Jeffrey 
pine (Pinus jeffreyi) takes the place ofthe yellow pinein the stands or may grow with itin mixture with 
other species. Other typesinclude the yellow pine-white fir type and the lodgepole pine type, where the 
lodgepole (P. contorta) growsin almost purestands. A number of minor types are also recognized. 
2027°—24-—_1 1 
