LOBLOLLY PINK 81 



the loblolly and longleaf pine. "Wherever in these upland forests an opening is made the short- 

 leaf pine gains over its associates, finding its only successful rival in the loblolly pine. It is in 

 the Southern States proverbial that in the upland forests " the pine is crowding out the hard- wood 

 timber/ 7 a fact early observed. The displacement is effected either gradually in the course of time, 

 or instantly when the removal of the original timber growth has been sudden. In the upper part 

 of the maritime pine belt, where it is associated with the longleaf pine, the latter is sure to be 

 replaced by the shortleaf species, often joined in the course of such invasion by the loblolly pine. 



LOBLOLLY PINE. 



The crops of seed are produced quite abundantly every year and copiously dispersed over the 

 vicinity of the mother trees by the wind, the offspring quickly taking possession of old fields 

 and clearings in the forest. 



The seeds germinate in the early spring. The ends of the cotyledons remain for a short time 

 after germination inclosed in the endosperm. The number of the germinal leaves (cotyledons) is 

 mostly six, rarely seven. At the time of the unfolding of the cotyledons the lower (hypocotyle- 

 donary) part of the axis of the plant is about 1 inch in length. The rootlets are half that length, 

 and are provided with several acropetal secondary rootlets. The caulicle grows rapidly, and is 

 soon covered w r ith the stiff, needle-shaped, and strongly serrulated primary leaves. Before the 

 spring season has x>assed the bundles of secondary or foliage leaves make their appearance in 

 the axils of the former. At the close of the summer season the plantlet has attained a height of 

 from 6 to S inches, the upper part of the stem covered with foliage leaves, the acerose primary 

 leaves of the lower part having completely withered. In examining a large number of young 

 plants never less than three leaves in a bundle have been found during this or any subsequent 

 stage of the growth. With the second year the primary leaves have all become reduced to the 

 ordinary form of the leaf bract — lanceolate, acuminate, with fimbriate white hyaline edges and tips. 



In all the specimens examined it was found that the growth of the main axis proceeded less 

 rapidly during the second season, but produced a regular whorl of from three to four lateral axes. 

 At the close of the second year the main stem rarely exceeds 10 inches in height. 



At the end of their third year the plants are from 18 to 20 inches high, the stem being from 

 one-fourth to five-sixteenths of an inch in thickness. The branches, forming regular whorls, are 

 erect and produce in their turn whorls of secondary order. The root system shows a correspond- 

 ing increase, the taproot being from 6 to 8 inches long, with numerous stout lateral roots. 



With the fourth year the loblolly pine enters seemingly upon the period of quickest growth. 

 As ascertained by many measurements, the trees at the end of their fourth year average 3 feet in 

 height and from one-half to seven-eighths of an inch in diameter, and at the end of the fifth year 

 measure nearly 5 feet and from 1 to 14' inches in diameter. At the beginning of the seventh year 

 the tree attains a height of 10 feet, and with the close of the first decade trees are found 12 to 16 

 feet high and from 2^ to 3 inches in diameter. Some trees begin to mature their first cones by the 

 tenth year. 



The above measurements were made in 1890 in the vicinity of Cullman, Ala., on trees taken 

 indiscriminately from the midst and near the border of a dense pine thicket covering a field plowed 

 for the last time in 1882, and from an adjoining opening in the forest protected from fire and but 

 rarely used for pasture. 



According to a number of measurements made of trees in the southern Atlantic States, the 

 Gulf region, and southern Arkansas, the loblolly pine reaches at the tenth year, on the average* 

 a height of 20 feet, doubling this height during the succeeding decade. During this period of 

 quickest growth the increase in height proceeds at the rate of 2 feet per annum, and trees twenty 

 years old average 4 J inches in diameter breast high. At the age of fifty years the trees are from 

 (55 to 75 feet in height (average about 70 feet) and 15 inches in diameter breast high. The annual 

 increase for this period of thirty years is about 1 foot in height and 0.35 inch in diameter. From 

 numerous observations it appears that the loblolly pine attains the fullness of its growth at the 

 age of one hundred years, with a height, on the average, of 110 feet and a diameter breast high 

 of 2 feet, the length of merchantable timber varying between 50 and 60 feet. The annual rate of 

 height growth during the second half century is about eight-tenths of a foot, and the diameter 

 H. Doc. 181 6 



