FORESTRY FOR 4-H CLUBS 



29 



Illustrative material. — Procure any good pictures showing how saw timber is 

 measured and estimated. Tables for scaling logs. 



Guides to study. — Measuring sawlogs; show how the diameter at the small end 

 is found by measuring inside the bark along an average line or averaging two 

 measurements at right angles. The diameter and length found, the approxi- 

 mate lumber contents is found by referring to a copy of some log rule. Probably 



Figure 23. — Showing a 4-H Club boy how to measure the height of a tree or the number of 16-foot 

 cuts with a cruiser's, Biltmore, or tree scale stick. 



the most common rule in use is the Doyle, although for small logs under 16 to 20 

 inches it is very inaccurate, because from one-third to one-half more lumber is 

 usually sawed out than is indicated by the rule. The International log rule (for 

 )4-inch saw kerf) gives more nearly what small mills cut from logs. (See p. 38.) 



