RESEARCH—-AN AID TO FOREST PERPETUATION. 
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conditions, the forest service has developed a successful method of con- 
verting the Nebraska bad lands into thriving plantations, and to-day 
there are about 3,500 acres which have been planted successfully at a 
cost of about 16 dollars per acre. The weary traveller, passing through 
the uninteresting sand-hill region in Nebraska, on the Billings Branch 
of the Burlington railroad, is now astonished, after hours of gazing 
at bare sand hills, to come suddenly upon green hills covered with ever- 
green trees. A desert has been converted into a forest which is now 
becoming a game refuge, and soon will be the playground for people 
in the prairie country, and a source of timber. This has been accom- 
plished only through persistent research in the face of many discourag- 
ing conditions. 
There are very few nowadays who will deny the protective value of 
forest cover on watersheds for irrigation purposes, water-power develop- 
ment, use of water for domestic purposes, and stream regulation and 
conservation in general. One of the main purposes for which national 
forests have been used in the west was to secure favorable conditions of 
water flow. It has been estimated that the service which the national: 
forests perform in the conservation of water for irrigation alone is 
worth two and one-half billion dollars annually. To determine accu- 
rately the effect which forest cover has upon the behaviour of streams 
for the better management of protective mountain forests, the forest 
service in 1909 undertook an experiment at Wagon Wheel Gap, 
Colo. Two small watersheds were selected and carefully surveyed as to 
cover, topography, and geological formation. Dams were built at the 
mouths of the watersheds, where automatic recording instruments regis- 
tered the amount of flow throughout the entire year—summer and 
winter. A net of meteorological observations was established in co- 
operation with the United States Weather Bureau on both watersheds, 
covering precipitation, temperature of the air, moisture of the soil and 
air, evaporation, and snow depth. For ten years no change in the forest 
cover was made, but last year one of the watersheds was denuded 
except for a strip of trees along the stream itself. Observations are 
now to be conducted for a series of years to bring out the effect of 
forest denudation. As all other conditions were made equal, any 
change in the flow of the stream from the forested and the deforested 
watershed must be due to the elimination of the forest cover on one 
of the watersheds. There is only one other experiment of this kind 
in the world, and that is in the Swiss Alps, not far from Zurich. The 
American experiment, however, is more thorough, and the results should 
be more conclusive, as in the Swiss experiment no water measurements 
are taken during the winter months, and the two watersheds selected 
differed from the very beginning in the density of their forest cover, 
and no denudation of any of the watersheds has taken place. The 
results of the experiment may be expected within the next five or ten 
years, as it is desired to carry the observations over a cycle of dry and 
wet years, and should settle forever the value of forest cover in stream 
control, and furnish an accurate basis of determining that value in any 
future engineering projects. ‘ 
In the field of wood utilization the results so far secured are no 
less.striking. In pulp and paper investigations about thirteen species 
of American timber, which heretofore were not known to be suitable 
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