ROLE OF FIRE IN CALIFORNIA PINE FORESTS 55 
spread on north slopes. If burning is postponed until north slopes 
_ will carry fire, the south slopes are then so dry that the fire partakes 
_of the nature of a summer burn. 
Broadly speaking, this area was divided into two inflammability 
_ types before the burning was started. 
Type 1 
| Ground cover.—Needles, short herbaceous material, occasional clumps of brush, 
scattered squaw carpet. 
| Soil—Varying from fine to very rocky. 
Fire-line construction.—From easy, where soil is not rocky, to moderately diffi- 
cult where much rock occurs and slopes are steep. 
TYPE 2 
Ground cover.—Open to medium brush, heavy squaw carpet, bear grass. 
_ Soil.—Generally rocky. 
Fire-line construction.— Medium difficult, due to brush and rocky soil. 
The first fire covered most of the ground classed under type 1 and 
little of that under type 2. The second fire again covered most of 
type 1 and crept in patches over part of type 2. The effect of the 
two fires on type 1 has been to reduce the amount of litter, but the 
natural replacement, plus the fuel created by the fires themselves, has 
made a third fire entirely possible. The effect on type 2 has been 
negligible. Relatively little of the rather heavy litter was consumed. 
What brush was killed has resprouted, and the dead material will fur- 
nish fuel for the next fire. 
As far as can now be forecasted, several more burns will be neces- 
sary to reduce type 2 areas to a condition of inflammability compar- 
able to that attained on type 1 to date. The latter probably can 
not be brought much lower than now; so long as timber is on the 
area, the natural fall of material will replace annually whatever is 
burned. On type 2 it may be possible by repeated efforts to reduce 
the brush to the form of low 1-year-old sprouts and to reduce the 
accumulation of litter. On such areas, however, fires are dangerous, 
especially during the preliminary reduction of inflammable material, 
when a sudden gust of wind may convert an innocuous creeping fire 
into a hot and damaging one, even in the early spring or late fall. 
From the standpoint of reducing hazard, it can not be said that 
much progress has been made. The more important and difficult of 
the two inflammability classes has seately een touched, and this 
general type of course 1s the one that light burning should reach if it 
is to have any success. 
In disposing of standing snags and down logs, the burning so far 
has been far from successful. Not more than 20 per cent of the 
standing snags have gone down, and not more than 45 per cent of the 
down logs have been reasonably completely consumed on the area 
burned over. The killing of trees by insects has more than offset the 
reduction of snags existing before the fire. 
Light fires may actually increase the amount of inflammable ma- 
terial by creating new sources of fuel. This increase occurs not only 
in the smaller material but also in large dead trees. On the area 
under discussion the first fire resulted in burning down a number of 
large trees. Some of these in falling came into close contact with 
other trees and clumps of advance growth and reproduction. The 
