42 LOBLOLLY OR NORTH CAROLINA PINE. 



loblolly pine is unable to maintain a foothold ; OR poorly di'ained soils 

 it is capable of establishing itself, but the growth is slow. On the 

 thoroughly drained rolling oak uplands, usually with clay soils, but 

 sometimes with shallow or coarse gravelly soils, young pine growth is 

 becoming common Avherever the hardwoods have been cut. The light 

 porous soils on fallow fields offer ideal conditions for the rapid develop- 

 ment of the roots of the young pines, so that the rate of increment of 

 young trees, even on dry, or sterile soils, if recently cultivated, is far 

 more rapid than on any, except the best virgin forest soils. (Plate 

 IV.) This is especially true of growth in diameter and of early 

 growth in height. On the coarse, most siliceous, and extremely dry soils 

 of the pine barrens, this pine occurs very rarely except on cultivated 

 lands. The wet, peaty, and mossy soils of white cedar swamps (juniper 

 bays), the fetter-bush swamps and peat bogs, the wet sour soils of 

 briery bays and pocosons (raw, acid peat) and the wet savannas are 

 unsuited to this tree. On such soils it seldom survives more than a few 

 years.* On peaty soils, which are so well drained that the peat is de- 

 composing and becoming humified, and so aerated that nitrification can 

 take place, it reproduces freely and becomes a large tree. On the 

 driest savannas and grassy flatwood lands, natural reproduction takes 

 place very slowly, perhaps partly on account of the frequent fires. 



Other factors being the same, a uniformly moist or damp soil is pre- 

 ferable to either a dry or wet one, or to one subject to great extremes of 

 moisture or drought, while a porous loam or sandy loam is preferable to 

 a clayey or compact soil or to a coarse siliceous one. (See Fig. 5.) 



LIGHT. 



The loblolly pine requires a full amount of direct sunlight for its best 

 development. During the younger stages of growth, and until the 

 period of rapid height-growth is passed, it will, however, endure much 

 lateral compression of its crown, without being dwarfed or crowded out, 

 but its capacity to endure shade and crowding is greatest on good sites 

 and least on poor sites. Its greater tolerance of shade on good sites 

 is due, at least in part, to the larger amount of available soil moisture. 

 It will even bear overshading for several decades and still be able to 

 make vigorous growth on the removal of the shade. This power of re- 

 covering from overshading, however, is limited to the early life of the 

 tree, and to favorable sites, though this limit varies much with the site. 

 On moist soils trees 40 to 60 years old can be found beneath a partial 

 shade growing slowly but remaining healthy. On medium dry soils few 

 small suppressed trees more than 50 or 60 years old can be found 

 growing beneath a partial cover, so that it seems probable that if trees 

 on medium soils are not offered light within that limit, they die. On 

 dry uplands soils, such as the red clays of the Piedmont, intolerance of 



*The symbiotic mycorrhiza, which occurs on the roots of the pocoson pine (P. serotina) and 

 enables it to grow in the wet and unaerated soils of pocosons, briery bays, fetter-bush bays, 

 reed swamps and peat bogs, does not occur on loblolly pine, which possibly explains the absence 

 of this tree from such sites. 



