ASPEN IN THE CENTRAL ROCKY MOUNTAIN EEGION 
23 
cutting, since it is well known that in coppice management summer 
cutting usually gives rise to sprouts which are killed back by frosts. 
Three plots were cut over at different seasons (spring, summer, and 
fall) to determine the effect in the case of aspen. The results 
showed that when the cutting takes place in the growing season 
aspen sprouting is delayed and is spread over two } T ears. The most 
sprouts followed the spring cutting and the fewest the summer cut- 
ting, but the present number is practically the same on all three areas, 
doubtless representing full stocking for the site, the average being 
16,500 sprouts per acre after seven years. (Table 11). 
Table 11. — Effect of season of cutting aspen on sprout reproduction 
Number of sprouts per acre at end of— 
Cut 
Year cut 
1 year 
2 years 
3 years 
4 years 
5 years 
6 years 
7 years 
Spring.. 
27, 598 
85, 456 
53, 628 
34,000 
40, 112 
44, 472 
34,880 
30, 084 
30, 956 
23, 980 
24, 416 
23, 108 
21,800 
i 22, 000 
i 20, 000 
19,600 
19, 620 
16, 568 
i 18, 000 
118,000 
Summer 
1 15,000 
Fall 
16,586 
Cut 
Average height at end of— 
Year cut 
1 year 
2 years 
3 years 
4 years 
5 years 
6 years 
7 years 
Spring 
Inches 
4.0 
Inches 
12.5 
16.0 
7.5 
Inches 
31.2 
33.5 
23.1 
Inches 
41.2 
46.6 
39.1 
Inches 
55.0 
56.4 
43.1 
Inches 
160.5 
162.0 
48.8 
Inches 
63.9 
64.9 
153.5 
Inches 
167.0 
Summer 
1 68.0 
Fall 
56.3 
1 Interpolated from curves. 
The slower height growth on the fall-cut plot is ascribed to its 
position, which exposes it to more frost damage than the other two. 
This factor was especially marked in reducing the growth in the 
seventh year. It is not believed that the season at winch the parent 
trees are cut can affect height growth of the reproduction after the 
third year. Between the first and second year after cutting there was 
still some sprouting going on, although it failed to counterbalance 
the losses from death. On the spring-cut plot it amounted to 3,045 
sprouts per acre and on the summer-cut plot 8,410 per acre. It can 
not be determined for the fall-cut plot on account of incomplete 
figures from the examination the first fall after cutting. After the 
second year new sprouts practically ceased to come in. 
REPRODUCTION OF CONIFERS ASSOCIATED WITH ASPEN 
The advisability of changing aspen stands over to conifer stands 
depends, in a measure, upon the possibility of getting an adequate 
reproduction of the conifers in a reasonable length of time. Com- 
pared to aspen, which springs up in one year after cutting to many 
times the minimum requirements for satisfactory stocking, the best 
that conifers can do must appear slight. Since, however, conifer 
stands will be managed on a selection system, and should contain con- 
siderable advance reproduction at the time of cutting, a slow, sus- 
tained regeneration may be satisfactory. A plot located in aspen ad- 
