NATURAL REGENERATION OF DOUGLAS FIR. Do 
DISTRIBUTION OF YOUNG GROWTH AFTER ONE FIRE IN FORESTS 
OF DIFFERENT AGE CLASSES. 
The Cispus fire of 1902 afforded an opportunity to study an area 
in which a single fire burned in two distinct age classes of forest. 
This area was in the region where the Tower Rock ranger station 
on the Rainier National Forest now stands. One age class was a 
mature Douglas-fir forest, and the other a second-growth stand of 
pole-sized, nearly pure Douglas fir about 40 years old. The young 
forests that followed after burning in each of the two age classes 
were strikingly different. 
In the mature Douglas-fir forest the conditions after the burn 
practically duplicated the conditions found on the Columbia burn. 
‘There was the same distribution of dense and sparse reproduction 
independent of the position of seed trees; there was essentially the 
same proportion of age classes in the reproduction, evidencing the 
greatest germination during the first two years after the fire; there 
was the same alternation of patches of the original brush cover and 
of reproduction, outlining the limits of the irregular ground fire. 
There was; moreover, abundant proof of the inadequacy of the sur- 
viving seed trees to restock a burned forest area of large extent. 
There were left on this burn numerous groups of living seed trees 
of Douglas fir and minor species ideally placed for a study of their 
influence in reseeding the area. In spite of the most favorable con- 
ditions of site for the germination and establishment of seedlings, it 
was invariably found that 1, 2, and 3 year old seedlings were limited 
to a radius not greater than 3 or 4 chains from seed trees. On the 
other hand, seedlings 10 and 11 years old were found everywhere, 
even at 12 chains, the maximum distance from seed trees attainable 
in the area. 
The destruction of a portion of the pole-sized stand of Douglas fir 
by the fire of 1902 produced peculiar conditions. When examined in 
1914 the ground was occupied by a dense cover of shrubs and ferns 
which grew up through a network of dead-and-down logs of small 
diameter. Reproduction occurred on this area in spite of the heavy 
brush cover, but it was comparatively scarce. The reproduction, in 
its struggle against the surrounding brush, developed the tall, lank 
“shade form” common to any thicket or forest-grown plant. The 
older seedlings occurred independently of the position of seed trees, 
but showed a tendency to be limited to moist sites, such as occur in 
ravines and hollows, where the conditions were most favorable imme- 
diately after the fire for germination and establishment. The 
younger seedlings (1 to 5 years old), however, showed an increase 
in density in the neighborhood of seed trees. Several seedlings of 
this class were found dead as a result of excessive drought and heat. 
in open places, but they were rarely found either lving or dead at 
distances over 6 chains from seed trees. 
The occurrence of two distinct age classes of seedlings and their 
positions in the burn with reference to seed trees indicate again that 
there were two sources of seed, namely, seed trees and the duff and 
soil in which seeds were stored. The reasons for the failure of 
seed trees to restock the burn have been discussed before. The 
scarcity of seedlings from duff-stored seed, however, presented a 
problem peculiar to this burn. The dense cover of shrubby and 
