FORESTRY. 521 
seem that a careful attention to the irrigation of the young trees on the 
more northern plateaus, where the rainfall and moisture are much less 
in amount, must be a sine qua non. 
. Assistant Surgeon V. Harard, U.S. A., ina botanical report submitted 
to me, says: 
In closing, I wish briefly to state my views in regard to the much-discussed subject 
of the treelessness of the western prairies, having had abundant opportunities during 
the past summer to verify the correctness of the various theories advanced. In the 
first place, the soil of these prairies, being mostly alluvial, does not originally contain 
tree seeds, and no spontaneous arborescent growth need be expected simply in upturn- 
ing it. When such seeds are planted, either by human or natural agencies, the nature 
of the soil and climatic conditions being generally favorable, they germinate, but as 
the young stem issues from the ground it becomes the prey of adverse circumstances, 
which prove fatal to its further development. These adverse circumstances may be 
several, but thé main and all-important one is the prairie fires which every fall and 
spring sweep over immense areas, leaving no vestige of vegetable life above the black- 
ened ground. Grasses and all annual plants may not be injured; their roots remain 
mostly intact, and they issue from their ashes as green and vigorous as eyer in the 
spring. Notso with trees and all perennials; endowed with a higher organization, 
the loss of their limbs is severely felt by the roots; these, affording more substantial 
food to the fire, are also more deeply burned than in the case of grasses. It follows 
that whenever a prairie fire visits outlying groves of ash, box-elder, or poplar, the less 
is but very slowly repaired, and after their charred remains become surrounded by a 
growth of young shoots a second visitation will probably extinguish their remnant of 
vitality. 
When trees are protected from fires, especially during the first few years, they grow 
and generally do well; even when shaken by winds and starved by drought their 
gnarled and stunted trunks will yet obtain a medium size. Such protection is afforded 
on bottom-lands from their position and from the moisture of the soil; also in the 
ravines, which drain the bluffs and open on the valley bottoms. In these ravines the 
capacity of the soil and climate to produce trees is clearly illustrated. The prairie 
fire, fanned by the breeze, advances rapidly over the open plateaus; a change of wind 
will divert its course, but not put it out; the moment it reaches the edge of a ravine 
it seems to hesitate, advances slowly, and soon, no longer.fed by the breeze, which is 
unable to reach it, dies out. In consequence such ravines are well wooded. Travel- 
ing along the Missouri or Yellowstone one sees large areas of level country totally 
stripped by fire, then depressions with white grass and brush, and again deep ravines 
and gorges with grass, brush, and groves of trees. 
These considerations contain practical suggestions for tree culture. It is impossible 
to prevent prairie fires, and laborious as well as expensive to protect any place from 
them in the open plains. Therefore it seems logical to seek such places for plantations 
as are naturally protected, and we generally find them in the Bad Lands. The Bad 
Lands, or at least most of them, are, I believe, susceptible of producing trees. Their 
suggestive name does not refer as much to the nature of the soil, which is often excel- 
lent, as to their irregular, broken, chaotic aspect, and the obstacles which they pre- 
sented to the march of the hardy Canadian voyagers who first explored them. JI am 
of opinion that the Bad Lands offer very favorable conditions for the successful eul- 
ture of such trees as grow spontaneously on or near the plains, such as pine, fir, red 
cedar, ash, box-elder, elm, quaking asp, willow-leaved poplar, alder, and birch. 
While agreeing with Dr. Harard that prairie fires are a very great 
cause of the treelessness of the western plateaus, still those very winds 
which fan the fires into their immense extent, also, in the absence of fire, 
Sweep over the prairies and cause a rapid evaporation of the moisture 
(this latter being an essential for the growth of trees), and the amount 
of rainfall is not sufficient throughout the year to contend against this 
evaporation. It may be that turning the soil would somewhat diminish 
the evaporation. 
In May, 1876, the rainfall was so great for three days that the expe- 
dition against hostile Sioux was delayed initsmarch. The morning after 
the rain ceased the column started, and I was amazed to see the condi- 
tion of the plateau above Fort Lincoln. The soil was to all appearance 
dry and crumbly. This must have been due to a very rapid evaporation, 
for a large amount of rain fell, and I conclude that the wind was an 
effective agent in quickening the evaporation. 
