File:American forests (17958492330).jpg

Title: American forests
Identifier: americanforests10natiuoft (find matches)
Year: [1] (s)
Authors: National Irrigation Association (U. S. ); New Jersey Forestry Association; South Jersey Woodmen's Association; American Forestry Association
Subjects: Forests and forestry -- Periodicals
Publisher: Washington (etc. ) American Forestry Association (etc. )
Contributing Library: Robarts - University of Toronto
Digitizing Sponsor: MSN

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1904 FORESTRY AND IRRIGATION . 207
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COUNTING KINGS OP ANNUAL GROWTH WITH A LENS. pines and one at Washington—under different departments and having no official connection. An explanation of the work of the tropical bureau was given in Forestry and Irrigation for April by Mr. Wilhelm Klemme. The work of the Bureau at Wash- ington is divided conveniently as fol- lows : Into preparation of working plans, surveys of forest reserves, the extension of forest areas by planting and otherwise, and investigation of for- est products. Each of these branches of work corresponds to an official divis- ion of similar name. The most extensiv^e branch of activity is the preparation of working plans for large tracts of forested lands. A work- ing plan, it may be said, is a carefully thought out scheme for the treatment of a specified area of woodland, based on a study of past and present condi- tions of growth and designed so to sup- plement and aid natural conditions that the forest shall continually produce and yield the largest quantity and the best quality of wood possible. In order to make such a plan, two main facts must be ascertained—the present amoiuit of w^ood standing and the amount of increase by growth each year. The observations which mu.st be made are of two kinds, known as forest sur- veys and stem analyses. fey means of the former the diameter of the trees on about one-twentieth of the total area is actually measutedwith large calipers. All the trees are cali- pered 33 feet on each side of compass lines run across the forest, either parallel or in a zigzag manner from one side to the other. Calipering thus for a mile along the line covers 8 acres. From such records may be' obtained an aver- age of the entire area, which is believed to vary by not more than one-tenth from the actual stand. Wherever the com- pass lines cross streams, strike the edge of the timber, or traverse slopes, notes of the distances are taken, which are the data by which a very fairly accurate timber map is drawn. Attention is also given to the value of streams for driving, the chances for splash-dams, camp sites, railways, and roads, and a mass of information is thus collected which may prove of the greatest

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