6 
Journal of Agricultural Research 
Vol. XI, No. i 
Tabl^ III .—Classification of young growth on township of Columbia burn studied a 
Species. 
Distance from 
seed trees. 
Douglas fir. 
Chains. 
(Over 10.... 
16—10. 
Western white pine.... 
[Over 10.... 
4 6-10. 
Noble fir. 
U -5 . 
[Over 10.... 
i6-io. 
Silver fir. 
lo -5 . 
[Over 10.... 
<6—10. 
Western hemlock. 
io-5. 
(Over 10.... 
|6—10. 
l °“5 . 
Per¬ 
centage 
of total 
area 
exam¬ 
Percentage of total 
number of seedlings 
found within each 
distance. 
Grand total percentage 
of all seedlings found. 
ined in¬ 
cluded 
in each 
Over 10 
6-10 
0-5 
Over 10 
6-10 
0-5 
dis¬ 
years. 
years. 
years. 
years. 
years. 
years. 
tance. 
89.9 
80.6 
7.0 
12.4 
] 
4. 6 
68. 5 
14. 4 
17. 1 
55 *o 
33*2 
11.8 
5 - 5 
54-9 
13*4 
31*7 
J 
98. 0 
25 - 3 
74 - 7 
1. 0 
20. O 
80. 0 
24.0 
76. 0 
1. 0 
20. O 
80. 0 
J 
89.7 
94. I 
3 * 0 
2.9 
I 
5-5 
9O.9 
2. 2 
6.9 
9*-4 
3*7 
4.9 
4 * 8 
67. 2 
8.8 
24. 0 
J 
85. 2 
93 * 5 
5 * 1 
I. 4 
] 
5*5 
75 *o 
25.0 
92.0 
6. 8 
1. 2 
9*3 
80. 0 
20. 0 
J 
78.4 
26. 5 
53 *o 
20. 5 
I 
9*3 
25.0 
45 - 8 
29. 2 
f 2 4 - 4 
5i*7 
23*9 
12.3 
T 9 *3 
51.6 
29. I 
J 
a Total area examined = 32.25 acres. 
The section and township records demonstrate that the occurrence 
of the age class o to 5 years is limited to the vicinity of seed trees or to 
localities which are topographically within the influence of these trees. 
Trees on a hillside above a canyon disseminated their seed over a wider 
range of territory than trees on level land, since the seed could be blown 
both down into the canyon over the nearer slope and also across to the 
opposite slope. 
There are no Douglas~fir seed trees on the section, except a single 
broken-topped one, but there are Douglas-fir seed trees within two or 
three chains of the northeast boundary of the section on the northwest 
slope of Little Lookout Mountain. These are from 100 to 300 feet above 
the areas containing the o- to 5-year-old class of reproduction; hence, it 
is entirely possible that they are responsible for the occurrence of this age 
class in the northern part of the section. The limited distribution of 
the o- to 5-year-old class, with reference to seed trees and topography, is 
consistent throughout the section and is particularly conspicuous at 
several points in the township (fig. 2). 
The transect from the west-central point of the section passes within 
two chains of green timber. The influence of this timber is shown in 
figure 2 by the occurrence of the o- to 5-year-old class for a distance of a 
few chains in the immediate vicinity of the seed trees in Texas Gulch. 
The remainder of the transect has a scattered stand of reproduction of 
the older classes, a very dense stand occurring in Poison Gulch almost 
1 mile from the nearest seed trees. This same condition is illustrated 
