32 



BULLETIN 308, U. S. DEPARTMENT OE AGRICULTURE. 



Table 17. — Yearly increment 1 per acre of fully stocked second-growth shortleaf 



pine in Arkansas. 



PERIODIC ANNUAL INCREMENT. 



Age. 



Scribner rule. 



Doyle rule. 





Solid measure. 



Quality. 



Quality. 



Quality. 



I. 



n. 



m. 



I. 



n. 



III. 



I. 



II. 



III. 



Years. 

 20 

 25 

 30 



Bd.ft. 



Bd.ft. 



Bd.ft. 



Bd.ft. 



Bd.ft. 



Bd.ft. 



Cu.ft. 



Cu.ft. 



Cu.ft. 



940 

 960 



620 

 630 











226 

 254 



156 

 174 



96 



340 



480 



360 



260 



35 



980 



640 



340 



620 



460 



280 



232 



166 



98 



40 



1,020 



640 



380 



740 



540 



320 



190 



142 



98 



45 



1,000 



640 



420 



840 



580 



340 



144 



118 



92 



50 



980 



650 



440 



840 



600 



360 



118 



106 



90 



55 



960 



680 



480 



760 



560 



340 



106 



94 



90 



60 



930 



750 



480 



680 



480 



320 



94 



92 



88 



65 



900 



690 



500 



620 



480 



320 



88 



86 



84 



70 



880 



690 



500 



580 



440 



300 



80 



78 



76 



75 

 80 





670 

 630 



520 

 500 



560 

 540 



440 

 420 



300 

 300 



72 

 66 



72 

 68 



72 

 68 







MEAN ANNUAL INCREMENT. 



20 

 25 



400 

 510 



220 

 300 











125 

 145 



85 

 100 



55 



105 



170 



110 



50 



30 



585 



355 



145 



220 



150 



85 



165 



115 



60 



35 



640 



395 



170 



275 



195 



110 



175 



120 



65 



40 



690 



425 



200 



335 



240 



140 



175 



125 



70 



45 



720 



450 



220 



390 



275 



160 



170 



125 



75 



50 



750 



470 



245 



435 



310 



180 



165 



120 



75 



55 



765 



490 



265 



465 



330 



195 



160 



120 



75 



60 



780 



510 



285 



485 



345 



205 



155 



115 



80 



65 



790 



525 



300 



495 



355 



215 



150 



115 



80 



70 



795 



535 



315 



500 



360 



220 



145 



110 



80 



75 



80 





545 

 2 550 



330 

 340 



505 

 505 



365 

 370 



225 

 230 



140 

 135 



110 



105 



75 

 75 







1 Based on 38 fully stocked sample plots; total area, 5.8 acres. Saw timber scaled to 5.5 inches in top 

 inside bark. Stump height, 1 foot. All trees 6 inches and over breast-high diameter were scaled. 



* A continuation of these figures indicates a culmination of mean annual increment at about 100 years 

 with an increment of about 560 board feet. 



ROTATION. 



It is always desirable to determine in advance the length of the 

 period through which the stand should be allowed to grow. This 

 depends largely upon (1) the age at which the average yearly growth 

 is greatest, (2) the kind of material desired, pulpwood, cordwood, or 

 saw timber, and (3) the total cost of producing the material. The 

 most reliable basis for determining the age at which to cut the stand 

 is the time when the average yearly production is the greatest. This 

 will then be modified in accordance with the kind of timber that is 

 desired. Other factors to be considered are taxes and protection 

 figured on the basis of compound interest, as well as stumpage values 

 and market demand. The age at which the highest net money re- 

 turn will be secured, or the financial maturity of the stand, may 



