LONGLEAF PINE. 



9 



Table 1. — Average growth of trees in height, diameter, and number of trees 

 per acre in well-stocked, even-aged longleaf pine stands on various qualities 

 of land. 



Age 



of 



stand. 



Height. 



Diameter l 

 (breast high). 



Approxi- 

 mate 



number 



of 



trees 



per acre. 2 



Better 

 land. 



Medium 

 land. 



Poorer 

 land. 



Better 

 land. 



Medium 

 land. 



Poorer 

 land. 



Years. 

 15 

 20 

 25 

 30 

 35 

 40 

 45 

 50 

 55 

 60 

 65 

 70 



Feet. 

 39 



50 

 58 

 63 

 68 

 72 

 75 

 78 

 80 

 82 

 83 

 84 



Feet. 

 24 

 34 

 42 

 48 

 54 

 58 

 61 

 64 

 66 

 68 

 69 

 70 



Feet. 

 10 

 19 

 27 

 33 

 39 

 43 

 46 

 49 

 52 

 54 

 56 

 57 



Inches. 

 5.3 

 7.0 

 8.1 

 9.0 

 9.7 

 10.4 

 10.9 

 11.4 

 11.8 

 12.1 

 12.4 

 12.7 



Inches. 

 3.6 

 5.0 

 6.0 

 6.9 

 7.6 

 8.3 

 8.8 

 9.3 

 9.6 

 10.0 

 10.2 

 10.4 



Inches. 

 1.9 

 3.1 

 4.0 

 4.8 

 5.5 

 6.2 

 6.7 

 7.2 

 7.5 

 7.8 

 8.0 

 8.2 



550 

 450 

 393 

 355 

 328 

 308 

 293 

 280 

 270 

 264 

 258 

 254 



1 Diameters measured at breast height, or 4^ feet above the ground. 



* The number of trees per acre varies considerably with age, but for any given age averages approxi- 

 mately the same on the better and poorer classes of land. Not only can the better lands support more 

 trees of a given size, but the trees are much larger in size at any specified age than on unfavorable situations 



On good lands, or good situations, it will be seen, for example, 

 that at 20 years longleaf pine reaches heights averaging about 50 

 feet : on medium land, about 34 feet ; and on poor land, about 19 

 feet. The medium class of land, for instance, would include the 

 loamy sands of the middle and upper Coastal Plains, and the last 

 class the poorer parts of the flatwoods and the very deep, dry sands. 

 The corresponding diameters, depending upon the situation, range 

 from 7 inches down to a little over 3 inches. During the next 10 

 years, the trees increase yearly in height at the rate of about 1.4 

 feet (16.8 inches) and in diameter nearly 2 inches. The average 

 diameter, as shown, usually represents an actual range of 4 to 6 

 inches, or 2 to 3 inches greater and 2 to 3 inches less. Likewise, 

 the average height would probably represent a range of 5 feet at 

 2' i years and as much as 10 feet at 50 years. The average diameter 

 at breastheight, for example, of trees in a 25-year-old stand on a 

 medium grade of soil is shown to be about 6 inches, and the trees 

 in that particular stand probably ranged in diameter mostly from 

 aboul H inches down to 4 inches. Table 1 shows that longleaf trees 

 growing in well-stocked stands on medium situations (land), have 

 an average yearly height growth of about 17 inches at 25 years, 12. 

 inches al 35, 6 inches ai 50, and 1 inches at GO years; and an increase 

 in diameter al tin- rate of about 1 inch in 5 years at 25 years, in 7 

 years al 35, in 12 years al 50, and in 16 years at the age of 60 (fig.3). 



There should be no misapprehension regarding the time necessary 

 to grow ;i crop of pines to ;i size thai is merchantable for timber or 

 turpentine, or aboul the dose relation existing between the tiumbei 



85927°— 22 2 



