Forest mensuration

This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1905 Excerpt: ... were placed to the right and the smallest to the left of the horizontal line. 5. Enter over the marked units the volume of the type trees (according to the composing factors, if required) in square units. A square unit might correspond with ten feet board measure, or with 1/100 of a cord, etc. 6. Draw a line joining the ends of the columns, adjusting it by an average curve. 7. Measure the space (in square units) between the curve and the horizontal line with the help of a planimeter; the number of square units giving directly the number of feet Doyle, or of cords, etc. If there are several assortments of volumes, several curves must be drawn. This method allows of separating the volumes of trees allotted to the several diameter classes. Mathematical errors are, practically, excluded. PARAGRAPH LVII. FACTORS GOVERNING THE SELECTION OF A METHOD OF VALUATION SURVEY. In the case of a valuation survey ("stock taking") in the woods, the following points must be considered: a. The degree of exactness required, which depends on the purpose at stake (e. g., scientific investigations, or preparation for logging, or taxation). b. The regularity, uniformity and soundness of the growing stock. c. The minimum diameter of logs; assortments; marketability of species. d. The possibility of cutting sample trees. e. The expense permissible. The question usually arises whether the entire forest or sample plots only must be surveyed. The answer depends on the configuration of the ground, uniformity of the growing stock as to size, age, species and quality of its components; further on the value of stumpage, on the accuracy required, on the available time and on the available funds. The following METHODS OF VALUATION SURVEYS might be distinguished: I. Cutting sample t...