228 



Yearbook of Agriculture 1949 



grade rules; grading methods or sys- 

 tems are different throughout the 

 country. Individual mills often have 

 grading rules of their own. Prices, of 

 course, depend on grades, and a top- 

 grade sawlog always has a higher 

 value than a lower-grade log. 



Selling logs by grade is more profit- 

 able than selling them ungraded, but 

 grading is so difficult for some prod- 

 ucts, particularly sawlogs, that advice 

 of a forester is generally necessary if ad- 

 vantage is to be taken of this practice. 



ESTIMATING STANDING TIMBER re- 

 quires training and practice. It is easier 

 to find the board feet in a sawlog than 

 in a tree before it is cut. If the small- 

 woodland owner is going to sell his 

 trees on the stump or ask for bids for 

 his standing timber, he must measure 

 the trees to determine how much he 

 has to sell. 



The owner should also have a 

 measurement of his trees for compari- 

 son with the measurement that a 

 timber operator or timber buyer may 

 have made at some different time. The 

 chances of losing money on a timber 

 sale are much less if the owner makes 

 his own estimate of the amount and 

 kind of products he has to sell. 



Three steps to follow in measuring 

 a tree are : 



1. With home-made calipers, a 

 carpenter's square, or a yardstick, 

 measure the diameter of the tree in 

 inches at breast height 4/2 feet above 

 the ground. 



2. Stand back from the tree and esti- 

 mate how many usable 16-foot logs 

 can be cut from it. A pole 1 7 feet high 

 (having a 1-foot allowance for stump 

 height) will be helpful in deciding 

 the number of 16-foot logs. 



3. Using the tree-scale tables, find 

 the volume of the tree in board feet. 

 If the tree is 18 inches in diameter and 

 2/> merchantable logs can be cut from 

 it, there will be 206 board feet in the 

 tree by the Doyle rule, or 292 board 

 feet by the International rule. As in 

 scaling logs, the Doyle rule gives a 

 lower volume than the International. 



These tables are made up from aver- 

 ages from the actual measurements of 

 many trees. The local forester can ad- 

 vise the landowner on the proper table 

 to use in his area and will have copies 

 of it. (See also pages 851-853.) 



Tree-measuring sticks may also be 

 available from the county agent, the 

 local forester, or the State extension 

 forester. The tree-measurement stick 

 will save time, and the volume of the 

 tree in board feet according to the 

 number of 16-foot usable logs can be 

 read direct. 



On the small forests of 50 to 100 

 acres, all the trees that are to be sold 

 should be counted and marked. As the 

 trees are marked and counted, the 

 volume of every tenth tree should be 

 measured. After all the trees have 

 been counted, add the volume of all 

 the trees that have been measured, 

 multiply this total volume by 10, and 

 you will have the estimated volume of 

 your entire stand. 



If the woodland is small, the best 

 way to get a good estimate of the 

 volume of the standing trees is to 

 measure every tree. The sum of these 

 measurements is the estimate of the 

 number of board feet in that part of 

 the stand that is to be cut, or in the 

 entire forest if all of the trees are 

 measured. 



In the larger forests, one can esti- 

 mate the volume of the entire stand 

 by measuring only sample plots. It is 

 important in making such an estimate 

 to obtain a fair sampling, or the sam- 

 ples should represent the average in 

 the best or worst part of the woodland. 

 Usually samples of a quarter or a fifth 

 of an acre in size are easier to work 

 with. Sometimes 1-acre plots are used 

 (1 acre is a 208-foot square). One- 

 quarter of an acre is a 104-foot square, 

 or 118 feet in diameter, if round. 

 Round plots are easier to measure and 

 to use in timber estimating than square 

 plots. 



Time will be saved if the trees are 

 marked for cutting at the same time 

 they are measured for board-feet con- 

 tent. Foresters sometimes recommend 



