INTRODUCTION. 
Forestry has to deal with forests. Forests subserve two purposes: 
supply of a most necessary raw material, and amelioration of the con- 
ditions of climate and water flow. 
In the semiarid and arid regions not only is tree growth established 
with more difficulty and expense, but except where irrigation can be 
had in full supply the trees will grow slowly after the vigorous juvenile 
period of twenty or thirty years, and remain of small dimensions, short 
bodied, and fit only for firewood. 
Protection, then, amelioration of climate, is the principal object of 
forest planting in these regions. Wood supply is the secondary con- 
sideration. 
The forests which furnish the enormous quantities of wood material 
used in this country, amounting in value to $1,000,000,000 in round 
numbers per year, grow in the humid regions, and will always grow 
there, because they are more favorable to tree growth, developing 
larger and better timber, more rapidly and cheaply, and that, too, on 
nonagricultural soil. 
The first interest, namely, our lumber supply, being so infinitely more 
important, most of the attention of the Division of Forestry was immedi- 
ately taken up with problems aftecting the rational use of our existing 
forest resources and their recuperation, somewhat to the exclusion of 
the questions which interest the tree grower of the West. 
The only way in which the division could have made itself useful in 
the latter direction seemed to be in field demonstration, namely, by 
establishing experimental plantings in which the adaptation of species 
to the climate and methods of using the same might be tested and 
object lessons exhibited. Practical difficulties of various kinds and 
deficiency of funds prevented the inauguration of such work until a 
plan of cooperation with the State agricultural experiment stations 
removed at least a part of these difficulties, and the abandonment of 
other important work furnished sufficient means to attempt this field 
work. This has now been carried on for three years under many draw- 
backs, the most detrimental of which is the difficulty of securing 
properly selected satisfactory plant material delivered in good condi- 
tion, and of adequate personal superintendence at the various stations 
during planting time. ? 
While the professors of horticulture who have kindly volunteered 
to take charge of these plantations unquestionably devote themselves 
aj 
