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MISC. PUBLICATION 3 9 5, U. S. DEPT. OF AGRICULTURE 



Practical things to do. : — Write an account of a method of scaling logs. Deter- 

 mine scale and estimate the number of feet in a given sawlog. Determine how 

 bolts and billets are measured. What constitutes a standard cord of wood? 

 Look up information about allowances made for defects in sawlogs, bolts, or 

 blocks, and in other material. 



F-370132 



Figure 24. — Estimating the saw timber in a tree by the use of a tree scale or cruiser's stick: A, If 

 the stick is held horizontally against the trunk of the tree at a specified distance from the eye, the 

 observer is able to read directly the diamter of the tree outside the bark. The standard is called 

 the breast-high diameter, and is taken at a height of Ay 2 feet above the average level of the ground. 

 B, The stick is graduated so that, when held a specified distance from the eye of the observer who 

 stands a specified distance from the tree, the observer can read the number of 16-foot-log lengths 

 of the tree. The principle is that of two similar triangles. 



Estimate the timber in standing trees: Find approximately the contents in 

 cords or board feet of lumber by measuring the diameter at breast height (4}i feet 

 above the ground), estimating or measuring the number of 16-foot log cuts in the 

 tree, and by using the information given in Farmers' Bulletin 1210 (figs. 22, 23, 

 and 24). Estimate the timber in a whole tract. Apply the same method to all 

 the trees on a measured one-tenth or one-quarter acre, thereby estimating the 

 contents per acre. Record the measurements by different species on a simple 

 blank form ruled in squares in two directions. 



