440 JOURNAL OF FORESTRY 



Equipped with these tables, the appraiser is ready for the field work. 

 After a general idea of the tract is obtained, sample strips should be 

 located which are representative of the timber. If more than one 

 stand type occurs, the sample areas should be located by such types 

 and the results computed for each type separately. Afterward the 

 results may be combined into a whole for the tract upon the basis of 

 the volume of the stand in each type. Probably the most accurate way 

 of locating the sample areas is by means of strips, one or two chains 

 wide, which are run at right angles to the slopes, much as is done in 

 reconnaissance. All trees which are to be cut upon the strip are re- 

 corded. The work may thus be done to advantage in connection with 

 sample marking. In recording a tree the first step is to measure the 

 diameter breast-high ; the second is to estimate the number of logs. By 

 reference to the taper table the top diameter of each log is ascertained. 

 Then the butt log is graded according to its conformance with the ten- 

 tative log grading rules, as judged by its outside appearance. Next. 

 the second log is so graded, and the operation continued for each log 

 in the tree. A notebook is provided, in which the diameter and grade 

 of each log are recorded. A practicable form for this notebook record 

 is shown by the two left-hand columns of Table 4. 



The computation of the proportion of grades from this field record 

 is simple, although it involves considerable work. The first step is to 

 calculate the log scale feet board measure for each diameter class 

 under each grade; separately for each species. This is readily done 

 by applying the decimal C scale rule. Next the overrun must be taken 

 into consideration, which may be done by calculating the overrun in 

 the log scale for each diameter class from the data given in the over- 

 run table (Table 2). The information at hand would then be in some- 

 what the same form as Table 4 : 



Table 4. — Grade I Yellow Pine {Sotind) 



The table showing per cents of grades from logs of various sizes 



