_Tree Studies._ Commercial tree studies are made of important tree species. The results are published in the form of monographs dealing with the range, silvicultural characteristics, growth, yield and management of each tree. These studies bring together all the important facts known about the tree described, such as: the industrial uses of the wood, the conditions under which the tree succeeds, the rate of growth in different situations, and the most suitable methods of management to secure the highest returns. Tables are included to show the volume of the trees at different ages and sizes, in cubic feet, in cords, in board feet, etc. Studies are also made of the life history and requirements of important forest trees, often in connection with commercial studies. Such studies cover: local, geographical, and commercial occurrence of the species, the species which are associated with it, the habit of the tree, its soil and climatic requirements for germination and growth, and the various matters connected with its reproduction. Such publications as these give the Forest officers much valuable information about the trees with which they are dealing, and also furnish the only sources of information to students in forest schools on the characteristics and requirements of the trees important in forestry in this country.
_Grazing Investigations._ Grazing investigations, being intimately connected with a great national industry, have received a considerable amount of attention. These studies are confined at present to grazing reconnoissance, the reseeding of depleted mountain grazing lands, studies in the best methods of handling sheep on the range, studies of the effect of grazing on the forest, identification of range plants, and the systematic elimination of poisonous range plants and predatory animals.
Grazing reconnoissance is a stock taking of the forage possibilities of a certain piece of range land. This work is usually done by organized parties, but a small amount is done also by Forest officers in spare time. This study aims to collect all the important grazing information, such as: the area of grazing lands, the kind of forage, the species of forage plants, the location of streams, springs, and other watering places for stock, the location of stock driveways, drift fences, and cabins, the location of timber lands that do and those that do not contain forage, and many other matters pertaining to the grazing of stock. The maps and field data secured furnish the basis for range improvement and more intensive range management. Up to date, over 12,288,885 acres of range lands have been covered in this way.