60 



HEIGHT 

 IN FEET. 



TIMBER PINES OF THE SOUTHERN UNITED STATES. 



^3Bf5.5'-7.0-f8.l-t9.6-f-ll.5-f-l3.0--J-l4.5--t--l6.0-- - 18.0--*-- 



---f --20.5- - *- - 21.3- 



DIAMETERS. 

 IN INCHES. 



Flo. 8 Growth of Longleaf Pine: Height, diameter, and cubic content** of average trera at 10, 20, etc., years of age. 



CONDITIONS OF DEVELOPMENT. 



Demands upon soil and climate. In its demands upon the soil this pine is to be counted among 

 the most frugal as far as mineral constituents, which are considered as plant food, are concerned, 

 if only the mechanical conditions which influence favorable soil moisture are not wanting. It 

 thrives best on a light siliceous soil, loamy sand or pebbles or light sandy loam, with a slightly 

 clayey subsoil sufficiently porous to insure at least a partial uuderdrainage and to permit unim- 

 peded development of the long taproot. Whenever the tree meets an obstacle to the development 

 of this root it remains more or less stunted. 



The luxuriance of the growth and increase in si/e of the timber, however, is greatly influ- 

 enced by the quantity of clay present, particularly in the deep subsoil, which improves mechanical 

 and moisture conditions. This is strikingly exhibited in the timber of the level pine flats west of 

 the Mississippi River, although the surface drainage is almost wanting and the underdraiuage 

 through the loamy strata slow, so that the surface of the soil remains damp or water-soaked for 

 the greater part of the year; the stand of timber of first-class dimensions exceeds considerably 

 that of the rolling pine uplands on the Atlantic slope and the lower part of the pine belt in the 

 Kastern Gulf region, which are poorer in clay. Evidently, although the underdrainagc is less 

 perfect, the moisture conditions during the dry season of the year, the time of most active growth, 

 must be most favorable. The same fact is apparent in the upper part of the coast pine belt in 

 Alabama and Mississippi, where upon the same area, with a smaller number of trees, the crop of 

 timber may be considered almost twice as heavy as that found on the pine barrens proper farther 

 south. On the soil of fine, closely compacted sand, entirely deficient in drainage as found in the 

 so-called pine meadows along the coast of western Florida, Alabama, and Mississippi, as well as 

 on the siliceous rocky ridges of central and northern Alabama, the tree is so stunted as to be of 

 little or no value for its timber. 



"It is neither temperature alone, nor rainfall and moisture conditions of the atmosphere alone, 

 that influence tree growth, but the relation of these two climatic factors, which determines the 



