REFORESTATION BY SEED SOWING IN THE NORTHERN 
ROCKY MOUNTAINS 1 
By W. G. Wahlenberg 
Northern Rocky Mountain Forest Experiment Station, Forest Service, United States 
Department of Agriculture 
INTRODUCTION 
Planting denuded forest lands with 
nursery stock is the dependable and 
established way to get new forest crops 
started. The fact, however, that it is 
in many places an operation involving 
heavy expenditures has led the Amer¬ 
ican forester to try out other methods 
to a considerable extent. His char¬ 
acteristic discontent with established 
practice as such, and his constant and 
persistent efforts to discover better 
ways, have led him to give not a little 
attention to field sowing as a possible 
short-cut in the artificial regeneration 
of forests. He considers that it is cer¬ 
tainly successful under many conditions 
in nature, and he is disinclined to 
abandon the idea, even under very ad¬ 
verse conditions, because the procedure 
appears to be simple and close to 
nature’s plan. When seeds germinate 
and the plants grow to maturity undis¬ 
turbed by man there is at any rate the 
certainty that the root system will be 
normal and that the trees will not be 
unduly subject to windfall or similar 
dangers which might result from 
planting. 
Such attempts at direct seeding in 
the northern Rocky Mountain region 
fall into two distinct classes: (1) The 
early extensive projects and (2) the 
later intensive experiments. 
EXTENSIVE EXPERIMENTS 
In 1910, large and very destructive 
fires occurred throughout the Rocky 
Mountain region, and the earnest desire 
to get new forest crops started led to 
extensive direct seeding projects during 
the following years. In all, 2,899 
acres were broadcast, 10,511 acres 
were sown by means of corn planters, 
and 1,969 acres were sown in spots—a 
total of 15,379 acres on the national 
forests in the western mountains. Of 
this area, 53 per cent was seeded to 
western white pine ( Pinus monticola), 
36 per cent to western yellow pine 
(P. ponderosa), 5 per cent to Douglas 
fir ( Pseudotsuga taxifolia), and 6 per 
cent to other species, such as lodgepole 
pine ( Pinus contorta), Engelmann 
spruce ( Picea engelmanni), Norway 
spruce (P. excelsa), western larch 
(Larix occidentalis), limber pine ( Pinus 
flexilis ), and hardwoods. Most of these 
areas have been examined at least once 
since sowing. 
Out of 343 trials, only 20 succeeded. 
Failures were found to be absolute in 
practically all cases, and all areas found 
to have less than 100 trees per acre 
were classed as failures. Broadcasting 
was tried generally without preparation 
of soil or use of poison. Of 101 at¬ 
tempts to reforest by this method, all 
failed except 9. The 153 attempts to 
reforest by the use of a corn planter 
failed likewise, with 9 exceptions. Of 
89 attempts to use the seed-spot 
method, only 2 were successful. 2 
There is one notable success, how¬ 
ever, on the Lolo National Forest. 
The ranger who made this sowing at¬ 
tributes the exceptional success to four 
things: (1) Prompt sowing after a 
burn; (2) seed poisoned with red lead 
and the area strewn with poisoned oats; 
(3) favorable sites; and (4) a moist 
season. In this case the sowing cost 
$4.46 per acre for labor. Other ex¬ 
penses brought the total cost to $6.31 
per acre. 
Failure is the outstanding fact in 
the vast majority of cases. It would 
be desirable, if possible, to look more 
closely into the reasons for the few 
instances of success, for the causes 
which made possible these exceptions 
might furnish some data for further 
observation. Unfortunately, recorded 
information is lacking concerning de¬ 
tails of sowing, site, or seed conditions, 
some of which may have been vitally 
important. 
1 Received for publication June 23 , 1924 ; issued June, 1925 . , 
2 In the cases both of broadcast and spot plantings there was one additional trial which appeared suc¬ 
cessful at the end of the first season but has not been examined since. 
Journal of Agricultural Research, 
Washington, D. C. 
( 637 ) 
Vol. XXX, No. 7 
Apr. 1,1925 
Key No. F-22 
