90 



LOBLOLLY OR NORTH CAROLINA PINE. 



Table 36. — Yield Per Acre in Cubic Feet of Stem Wood, Without B.\rk, but Including Stumps 

 AND Tops of All Trees Six Inches and Over Breasthigh in Fully Stocked Unthinned 

 Stands op Loblolly Pine at Different Ages on Different Quality Sites. 



Table 37 gives practically the material which Avould be available for 

 conversion into bolts, heading, staves, box boards, or for paper pulp stock. 

 The yield is given both in long cords of 160 cubic feet without bark and 

 in standard cords of 128 cubic feet with bark. The greatest average 

 annual yield in standard cords on Quality I is obtained by cutting the 

 stand at about the age of 30 years; or Quality II at about 40 years; or 

 Quality III at about 50 years. In old field stands on dry sites there is 

 an actual decline in the volume of the stand between 40 and 60 years 

 of age, according to site. This is due to the rapid natural thinning as 

 the trees become intolerant of shade or when the demands on soil mois- 

 ture increase above the available supply. Plate XVI shows Quality II 

 stand at the age of greatest average annual yield. 



hi Board Feet. 



Table 38 gives the yield in board feet, 1-7 inch saw^ kerf, of all trees 

 6 inches and over in diameter breasthigh in fully stocked unthinned 

 stands of loblolly pine on different quality sites at different ages, on 

 the basis of three to four logs to the large trees and of top diameters 

 given in Table 32. Xo allowance is made in this and following tables 

 for crooked logs in which the crookedness exceeds 2 inches for waste or 



