LOli LOLLY OK MUCTII ; \I;<UI.N.\ 1M.M-:. 



143 



of the area by means of strips. After ohiaining tin- average number of 

 trees of each diameter per acre the proportion of the total area which is 

 occupied by these trees can be ascertained by means of Table 74, which 

 which gives the crown space in per cent of an area required for the 

 growth of trees of different diameters. If these trees are separated into 

 diame'.-r groups and the diameter of the average tree in each group 

 determined, the average age of the trees in each diameter group can he 

 calculated by means of Tables 4:, ; , }:!, and 1-4. Knowing the quality site, 

 and the approximate age of the groups, and the proportion each group 

 contributes to the stocking, it is possible, by means of the yield tables to 

 obtain the approximate yield from the subordinate as well as the domi- 

 nant crown classes at the period desired. 



TABLE 74. CROWN SPACE IN PER CENT or ACHE REQUIRED BT DOMINANT TREES or LOBLOLLY 

 PINE or DirrERENT DIAMETERS ON DIFFERENT QUALITY SITES. 



INCREASING T1IK REVENUE FROM TIM I'.KKI.AXD. 



Reducing Waste in Logging. 



A considerable source of loss of timber is the cutting of extra long 

 logs. The usual length of allowance is four inches above the scale 

 length of the log. Logs are frequently cut, however, with 6 or 8 inches 

 extra length. If cutting is carefully done a 3-inch allowance is suf- 

 ficient for logs less than 14 inches in diameter and 4 inches for logs of 

 larger diameter. 



Another source of loss is in cutting extra high stumps. This is sel- 

 dom done now, however, except by contractors, small mill men. or 

 unskilled farm laborers, hired during the winter months. As a rule, 

 stumps are cut as low in loblolly pine logging as is possible. On- 



