92 



LOBLOLLY OR NORTH CAROLINA PINE. 



standard 7x7 inch ties. The greatest average annual yield of tie tim- 

 ber is obtained on Quality I when the stand is about 40 years old; on 

 Quality II when about 50 years old ; and on Quality III when about 55 

 years old. Cutting to 11 inches in diameter gives the yield of all trees 

 large enough for crate veneer stock. (Plate XIV shows a Quality II 

 stand, culled, 60 years old, jdelding about 30,000 feet per acre ; Plate XY 

 an unthinned stand about 80 years old, yielding about 40,000 feet per 

 acre.) 



Table 42 gives the total number of trees 6 inches and over, the average 

 diameter of all trees and the annual rate of decrease in the number of 

 trees with the increase in the age of the stand. This table is of value in 

 showing which portion of the yield is contributed by the trees in the 

 dominant crown class. It shows the approximate number of trees which 

 would be removed in thinning unthinned stands by deducting the num- 

 ber of dominant trees from the total number of trees. (See page 159.) 



Tables 43 and 44 show the number of trees 9 inches and over and 11 

 inches and over per acre respectively and their average diameters at 

 different ages in fully stocked stands. By combining Table 42 with 

 Tables 43 and 44 the number of trees over 6 inches in diameter left per 

 acre after cutting to 9 and 11 inches in diameter breasthigh can be 

 obtained. 



Table 38. — ^Yield Per Acre in Board Feet of All Trees Six Inches and Over in Diameter 

 Breasthigh to Top Diameter Given in Table 32, in Fully Stocked Unthinned Stands of 

 Loblolly Pine at Different Ages on Different Quality Sites. No Allowance for Exces- 

 sive Crook, Waste or Breakage. 



