RATE OF GROWTH. 45 



elsewhere in the Southern Appalachians. A group of 12 trees, measured on 

 Tuskeegee Creek, Jackson County, N. C, at an elevation of 1,700 feet, had an 

 average age of 104 j^ears, and had reached onh' 11 inches in diameter, or their 

 diameter growth was less than 1 inch per decade. The average height of this 

 group was only 84 feet. The black pine (northern pitch pine) shows a somewhat 

 greater diameter growth than the shortleaf pine, but its height growth is not 

 so rapid and it is a shorter tree. 



The scrub pine never attains a large size, and although its rate of growth 

 is at first more rapid than that of the shortleaf pine, it is at length outgrown. 

 It seldom attains a greater age than .00 years, and most of the old trees seem 

 to be between 80 and 90 3"ears of age. 



Average increase in diameter, on stump, of a group of fire trees of scrub pine, at 10-year intervals. 



Diameter in 

 inches. 



10 years 1.4 



20 years 5. 2 



30 years 7. 4 



40 years 9. 2 



50 years 11.0 



60 years 12.2 



70 years 13. 



80 years 13. 4 



90 years 14. 



These trees had an average height of TO feet; the average length of stem 

 was 49 feet; the merchantable timber amounted to 180 feet B. M. per tree. 

 The s(;rub pine is too small to be of value as a timber tree, but its rapid growth 

 to the sixtieth year along the foothills of the Blue Ridge, and its heavy yield in 

 full-stocked areas, may make it of value as a fuel producer. It is rapidly 

 increasing, especially in the culled woodland along the Blue Ridge. 



Hemlock. Hemlock is one of the slowest growing trees of the Southern 

 Appalachians. Three groups of trees were measured at different elevations in 

 Mitchell County, N. C. All were growing on good soil and under average condi- 

 tions. These measurements show that hemlock has an average annual accretion 

 of less than 3 feet B. M. per single tree, while white pine under the same 

 conditions gains nearly 5 feet B. M. per tree. There is very little young growth 

 of hemlock, and it is improbable that it will be largely represented in the 

 second-growth woodland. 



