130 TIMBER PINES OF THE SOUTHERN UNITED STATES. 



follows quite closely the isothermal line of 50° F.; westward, in tbe direction of the Gulf Coast, 

 the isothermal line of 60^. The meau temperature of the winter along the northern limit is about 

 45°, with the lowest temperature only occasionally falling below lO"^ F. This tree approaches 

 the Appalachian zone only under the influence of a peninsular clime between the Delaware and 

 Chesapeake bays. 



Tlie Loblolly appears to be indifferent to the wide differences in the amount of atmospheric 

 precipitation existing within the vast range of its distribution. Extending from Florida (isotherm, 

 74^) to the 39= of north latitude on the Atlantic Coast (isotherm, 50°), it is found of equal thrift 

 on the Gulf shore, with its damp air and annual rainfall exceeding 64 inches, and in the flat woods 

 of Texas, where the mean annual precipitation is only one-half that amount, with a mean of 6 

 inches during the winter months. In fact, the Loblolly Pine is found most frequently and is more 

 widely distributed in the districts of lesser precipitation. It is certainly more dependent on the 

 supplies of soil moisture than upon atmospheric humidity. 



RELATION TO LIGHT AND ASSOCIATED SPECIES. 



This species is less exacting in its demands for direct sunlight than the kindred species within 

 its range. To this relation may be ascribed the success which it achieves in the struggle for the 

 possession of the soil with the Shortleaf Pine. Observing this contest as it is going on between 

 the competing species in the forest, the conditions of the soil being equally favorable, the Loblolly 

 Pine, under the cover of shade, outstrips the Shortleaf Pine under the same conditions; and, on 

 the other hand, where the sunlight has had unhindered access, it gives way to its competitor, 

 being then subjected to the disadvantage resulting from a speedier desiccation of the soil. 

 Through such influences it is that, under conditions seemingly equally favorable to either one of 

 these pines, now the one and now the other is found to predominate. 



In the deep forests covering the rich swampy lands of the coast regions, the Loblolly Pine 

 forms comparatively a small part of the rich and varied growth consisting chiefly of deciduous 

 trees, Black Gum, Sweet or Red Gum, Water Oak, and Mockernut, to which in the lower South the 

 Magnolia, Sweet Bay, Red Bay, and Cuban Pine are to be added. Although requiring less sunlight 

 than most pines, in the gloomy impenetrable shade of these den.se forests the progeny of the 

 Loblolly Pine has no future, especially as these lands once cleared are devoted to tillage, being of 

 great agricultural value. 



On the lands of a poorer, more exposed soil in the maritime plain of the southern Atlantic 

 States, in Virginia and North Carolina, and in southwestern Texas, this pine forms more or less 

 compact forests. In these forests the tree is always succeeded by its own progeny, either in the 

 course of nature or after the artificial removal of the original forest growth. On the coast of 

 Georgia, in Florida, and in the coast plain of the eastern Gulf States, the Loblolly Pine is scattered 

 among the Cuban and the Lougleaf Pine; there its second growth meets a formidable competitor 

 in the first named of these species. In the flat woods, deprived of drainage, the Cuban Pine is 

 always found to vastly outnumber the Loblolly among the young forest growth. In the upper part 

 of the great maritime pine belt the Loblolly Pine is frequently found among the mixed growth of 

 Magnolia, Spanish, Red, Post, and Blackjack oaks, Mockernut and Pignut Hickory, Shortleaf 

 Pine, and Southern Spruce Pine. Throughout this region the tree takes almost undisputed 

 possession of the old fields. 



In the interior, on the uplands of oaks and Shortleaf Pine, tbe Loblolly is sure to gain the 

 upper hand and to retain its hold among the young forest growth, giving way to its most aggressive 

 competitor, the Shortleaf Pine, only wiien under the disadvantage of a greater exposure and a 

 greater lack of moisture in the soil. 



ENEMIES. 



Principally confined to low, damp localities, not easily liable to invasion by the frequent 

 conflagrations which scour the Southern pine forests, the Loblolly Pine suffers less from destruction 

 by fire than any other species. In virtue of the inherent facilities foi- its natural renewal resulting 

 from its fecundity and from the rapidity of its development from the earliest stages of growth, 

 any damages inflicted by that agency are more easily repaired. The same causes afford it also 



