24 BULLETIN 1200, U. S. DEPARTMENT OF AGRICULTURE. 
herbaceous growth on the area might account for a scarcity or ab- 
sence of seedlings from “ wind-blown” seed, but it would not ac- 
count for the scarcity of seedlings from stored seed. Reproduction 
from stored seed, as a rule, starts at the same time as the brush on 
the burn, and does not come in after the brush has taken possession 
of the ground. Hence, the reproduction has merely to hold its own 
in height growth with the brush, and this it has frequently proved 
itself able to do. 
The reason for the scarcity of reproduction from stored seed must. 
be sought in the condition of the stand. The fire burned, not in an 
old virgin forest, but in a young forest, which was itself successor 
to a burned mature forest. The earlier fire (1860) killed most of 
the veteran trees which were the chief source of seed then stored 
in the forest floor. From the stored seed of the old forest there 
resulted a thrifty second growth of almost pure Douglas fr. How 
complete this stand was could not be determined; it is likely that there 
were openings resulting from ground fire in parts of the original 
burn. In 1902, at a time when this young forest was seeding, but 
long befere it had shed enough litter on the ground for the storage 
of its seed this forest also was destroyed by fire. In the hot fire of 
1902 some of the duff was undoubtedly burned and consequently 
some of the stored seed. The result of this combination of cir- 
cumstances was the occurrence of scattered, inadequate reproduc- 
tion amid a rank growth of brush and weeds. The reproduction 
was more plentiful in moist or depressed spots, where the duff had 
in a large measure, escaped the ground fire and provided favorable 
conditions for the germination and establishment of seedlings after 
the fire. 
The findings on the Cispus burn corroborated those established on 
the Columbia burn, and brought out additional facts regarding the 
effect of the original stand upon the reproduction that follows after 
a single fire. 
Where the young stand of timber was destroyed by fire, only a 
thin stand of reproduction occurred on the burn. The reason for 
the light reproduction was found in the small accumulation of duff 
on the floor of the-young forest, and in the smaller accumulation of 
seed in the duff which resulted from the limited production of 
seed by the young trees. 
EFFECT OF SOIL CONDITIONS ON DISTRIBUTION OF YOUNG 
GROWTH FOLLOWING ONE FOREST FIRE. 
Even where a mature forest of uniform type is burned by a single 
fire, densely stocked areas of young growth may occur alternately 
with sparsely stocked or barren areas. 
Where reproduction does not follow the first forest fire the explana- 
tion often lies in the condition of the soil. An extensive area on 
which practically no young growth followed the first fire was found 
in the Cispus burn of 1910 along the Johnson Creek Trail. The 
area was characterized by light volcanic ash soil, which, no doubt, was 
the chief reason for barrenness of the area after one fire. This type 
of soil is so dry and porous that a fire will heat it, burn all the duff, 
and even destroy the seed that may be buried in the mineral soil, 
so there is no possibility of reproduction from seed stored in the 
