LIFE HISTORY OF SHORTLEAF PINE. 
29 
Table 9. — Height growth of shortleaf pine, based on age, in Arkansas and North 
Carolina — Continued. 
PIEDMONT REGION, NORTH CAROLINA. 
Age (years). 
Height. 
Age (years). 
Height. 
Maximum. 
Average. 
Minimum. 
Maximum. 
Average. 
Minimum. 
5 
Feet. 
22 
48 
63 
69 
71 
73 
74 
75 
Feet. 
13 
29 
42 
50 
57 
61 
63 
65 
Feet. 
45 
Icet. 
75 
76 
76 
77 
77 
77 
78 
78 
Feet. 
67 
68 
69 
69 
70 
70 
70 
71 
Feet. 
40 
10 
10 
15 
20 
25 
29 
33 
36 
50... 
43 
15... 
55 
45 
20 
60 
48 
25... 
65 
49 
30 
70 
51 
35 
75 
53 
40 
80 
55 
During early life the terminal leader of shortleaf pine commonly 
forms from two to four secondary or false terminal nodes during the 
growing season. These are accompanied by false rings of growth in 
the wood, usually plainly marked and apt to be mistaken for true 
rings. 
The influence of side light upon height growth is well illustrated in 
figure 5, showing a 10-year-old stand of shortleaf with the east and 
west side light cut off by an adjacent stand. The heights increase 
from 2 feet near the margin to 22 feet under full light. This illus- 
trates very well the need of light for development, and, at the same 
time, the power of endurance of shortleaf under limited light supply. 
A 9-year-old stand with 3,800 trees per acre averaged 19 feet high 
as compared with only 16 feet for a near-by stand of the same age 
and on similar soil with 12,200 trees per acre. Two adjacent young 
stands, similar in all points except tree density, averaged 9 feet high 
for 4,100 trees per acre and 5 feet high for 32,000 trees per acre. 
DIAMETER. 
The rate of diameter growth of shortleaf pine is intermediate be- 
tween that of loblolly and that of longleaf pine, the slowest of the 
important southern pines. Besides the well-defined annual rings of 
wood which clearly record diameter growth, from two to four ter- 
minal nodes in the stem of the tree, accompanied by slight resting 
periods in the tree's activity, usually occur during the period of 
vigorous growth in earlier life. These growth periods are recorded by 
fine lines of denser wood within the true annual rings. Periods of 
injury, caused by insect attack, fire, or severe drought during which 
growth is temporarily checked, usually have the same effect. Such 
lines, forming false rings, are frequent in shortleaf pine, and must be 
distinguished in examining a cross section for age. Prominent bands 
of wood stained brown in color are particularly apt to be found in 
