PRACTICAL ARBORICULTURE TL? 
Missouri, Yellowstone, Platte, Kansas, Arkansas, Red, Canadian, etc., and the 
Rio Grande of the South, an international waterway, all rise in the Rocky 
Mountain Range. 
The regularity of flow in all these streams is entirely dependent upon the 
snowfall and its period of melting in this high mountain range. The South 
feels the mighty influence of this power as the strength of the embankment 
and the height of the levees along the Mississippi and numerous rivers and 
bayous are controlled by this one cause; while the navigation of Western 
rivers, the period of navigable depth, and consequently the regularity of West- 
ern commerce is also dependent upon the length of time occupied by these 
mountain snows in melting. 
A very large area of the United States is, to a greater or less extent, arid, 
must be irrigated to enable vegetation to exist and thus provide homes and 
farms for the rapidly increasing population. 
The extent of the land which may be reclaimed from the desert, the 
amount of wealth which must be expended in reservoir construction and 
maintenance by the Nation, and as a consequence how great a population the 
Nation may support, in the semi-arid bel:, will all depend upon conditions 
existing in the Rocky Mountain region, and which may, to a very large extent, 
be controlled by man, and this again will depend upon the area of the forest 
cover upon the mountain slopes. The great number of bridges which in the 
past few years have been swept away by floods of water from the too rapid 
melting of snows attest the vast influence of the Continental Divide upon the 
railway commerce of the West, while the cities submerged, homes and prop- 
erty destroyed, and lives lost in these floods are in evidence to show the 
destruction which may be caused by water uncontrolled, and which are influ- 
enced by conditions in this elevated mountain region. 
IMPORTANCE OF THE FORESTS. 
So long as the mountain slopes are covered with timber, the snow is held 
in place, shaded from the rays of the sun, and thus gradually, with the advent 
of warm weather, is melted away, requiring several weeks to entirely disap- 
pear. Although, of course, at a few points in the higher mountains, and upon 
northern slopes, some snow remains throughout the year. 
Removal of the forests, baring the rocks, enables the sun’s rays to reach 
the snow-beds and melt it very rapidly. Thus the great volume of snow is 
converted into water in a brief period, and, rushing down the steep gulches, 
swells the streams to overflowing, creating havoc all the way to the sea. 
More than this, the great rivers in the lower and level country, which have 
thus tested the capacity of their banks and levees along their lower courses, 
are soon reduced in volume, in depth, and in their capacity to bear the coun- 
try’s commerce, 
To remedy this condition and increase the navigable depth of rivers, the 
Government expends annually many millions of dollars, under the enormous 
appropriation for rivers and harbors improvement. Yet very much of this 
work is ineffectual because the prime cause is lost sight of and only the 
