The Genus Pinus Part 16

Among its a.s.sociates this species is recognized by its large white fringed bud and its elongated cone. Its leaves attain, on vigorous trees, the maximum length among Pines, but on most trees the leaves do not differ in length from the longer forms of those of P. caribaea or P. taeda. A peculiarity, which it shares with P. caribaea, is the deciduous scaly bark of mature trees, constantly falling away in thin irregular scales.

Plate XXVIII.

Figs. 242, 243, Cones and seed. Fig. 244, Bud. Fig. 245, Magnified leaf-section. Fig. 246, Magnified cells of the leaf-endoderm. The dermal tissues of fig. 249 also apply to this species.

[Ill.u.s.tration: PLATE XXVIII. P. PAl.u.s.tRIS (242-246), OCCIDENTALIS (247-249)]

44. PINUS CARIBAEA

1851 P. caribaea Morelet in Rev. Hort. Cote d'Or, i. 105.

1864 P. bahamensis Grisebach, Fl. Brit. W. Ind. 503.

1880 P. Elliottii Engelmann in Trans. Acad. St. Louis, iv. 186, tt. 1-3.

1884 P. cubensis Sargent in Rep. 10th. Cens. U. S. ix. 202 (not Grisebach).

1893 P. heterophylla Sudworth in Bull. Torrey Bot. Club, xx. 45.

1903 P. recurvata Rowley in Bull. Torrey Bot. Club, x.x.x. 107.

Spring-shoots multinodal, more or less pruinose. Buds pale chestnut-brown. Leaves in fascicles of 2 and 3, or more in its southern range, from 12 to 25 cm. long; resin-ducts internal, hypoderm biform, endoderm with thin outer walls. Conelets reflexed on long peduncles, mucronate. Cones from 5 to 15 cm. long, ovate or oblong-ovate, symmetrical, deciduous and leaving often a few basal scales on the branch; apophyses l.u.s.trous, rufous-brown, tumid, the umbo somewhat salient and minutely mucronate.

The northern limit of the range of P. caribaea extends from the coast of southeastern S. Carolina through southeastern Georgia and southern Alabama to southeastern Louisiana. It is a.s.sociated with P. pal.u.s.tris, taeda, serotina, echinata and glabra in this part of its range. It continues through Florida, where it encounters P. clausa. On the Bahamas it is the only Pine. On the Isle of Pines it finds in P.

tropicalis another a.s.sociate. It also grows in Honduras and Guatemala.

The wood and resin of this species are of such excellent quality that no commercial distinction is made between P. caribaea and P.

pal.u.s.tris.

Plate XXIX.

Fig. 250, Cone from the Isle of Pines. Fig. 251, Small form of cone.

Fig. 252, Large form of cone and binate leaf-fascicle. Fig. 253, Conelet. Fig. 254, Magnified sections of leaves from binate and ternate fascicles. Fig. 255, Habit of the tree, contrasted with a tree of P. pal.u.s.tris in the middle-distance.

[Ill.u.s.tration: PLATE XXIX. PINUS CARIBAEA]

45. PINUS TAEDA

1753 P. taeda Linnaeus, Sp. Pl. 1000.

1788 P. lutea Walter Fl. Carol. 237.

1903 P. heterophylla Small, Fl. Southeast. U. S. 28 (not Sudworth).

Spring-shoots multinodal. Leaves in fascicles of 3, from 12 to 25 cm.

long; resin-ducts medial, sometimes with an internal duct, hypoderm biform, endoderm with thin outer walls. Conelets erect, their scales prolonged into a sharp point. Cones from 6 to 10 cm. long, ovate-conic, symmetrical; apophyses dull pale nut-brown, rarely l.u.s.trous, elevated along a transverse keel, the whole umbo forming a stout triangular spine with slightly concave sides.

The species ranges from southern New Jersey to southern Arkansas, Oklahoma, eastern Texas and southwestern Tennessee, but does not occur in the lower half of the Florida peninsula. It is an important timber-tree, manufactured into all descriptions of scantlings, boarding and finish, but the wood is of various qualities. It may be recognized by the spine of its cone in both years of growth. Excepting the formidable armature of the cone of P. pungens, the spines are the strongest and most persistent of all the species of eastern North America.

Plate x.x.x.

Fig. 264, Cone. Fig. 265, Leaf-fascicle. Fig. 266, Magnified leaf-section. Fig. 267. Magnified scales of the conelet.

46. PINUS GLABRA

1788 P. glabra Walter, Fl. Carol. 237.

Spring-shoots multinodal. Bark-formation late, the upper trunks of mature trees smooth. Leaves in fascicles of 2, from 9 to 12 cm. long; resin-ducts medial, hypoderm weak, sometimes of a single row, biform when of two rows, endoderm with thin outer walls. Conelets reflexed, mucronate. Cones from 4 to 7 cm. long, reflexed, ovate, symmetrical, deciduous on some trees, persistent on others; apophyses pale dull nut-brown, thin or slightly thickened, the p.r.i.c.kle usually deciduous.

A tree that sometimes attains important dimensions, growing singly or in small groves from the neighborhood of Charleston, S. C., to eastern Louisiana and central Mississippi, most abundant in a strip of territory on either side of the northern boundary of Florida. Among the Pines of the southeastern United States it is the only species with late bark-formation, and is therefore easily identified.

Plate x.x.x.

Fig. 256, Cone. Fig. 257, Enlarged scale of the conelet. Fig. 258, Leaf-fascicle and magnified leaf-section. Fig. 259, Dermal tissues of the leaf magnified, with a double row of hypoderm cells.

47. PINUS ECHINATA

1768 P. echinata Miller, Gard. Dict. ed. 8.

1788 P. squarrosa Walter, Fl. Carol. 237.

1803 P. mitis Michaux, Fl. Bor. Am. ii. 204.

1803 P. variabilis Lambert, Gen. Pin. i. 22, t. 15.

1854 P. Royleana Jamieson in Jour. Hort. Soc. Lond. ix. 52, f.

Spring-shoots multinodal, somewhat pruinose. Bark forming early, rough on the upper trunk. Leaves in fascicles of 2 and 3, from 7 to 12 cm.

long; resin-ducts medial, with an occasional internal duct, hypoderm weak, biform when of two rows of cells, endoderm with thin outer walls.

Conelets mucronate. Cones from 4 to 6 cm. long, ovate-conic, symmetrical, often persistent; apophyses dull pale nut-brown, thin or somewhat thickened along a transverse keel, the umbo salient, the mucro more or less persistent.

This species ranges from southeastern New York to northern Florida, to West Virginia and eastern Tennessee, and through the Gulf States to eastern Louisiana, eastern Texas, southern Missouri and southwestern Illinois. It is extensively manufactured into material of all kinds that enters into the construction of buildings. It differs from P.

virginiana in its longer leaves, brittle branches, and much greater height, from P. glabra in its rough upper trunk, and from both by the frequent presence of trimerous leaf-fascicles.

Of the six or seven pines of the southeastern United States, this species covers a larger area and ascends the slopes of the Alleghany Mountains far enough to meet the northern species, P. virginiana, P.

rigida, and P. strobus. Unlike the western members of this group, P.

echinata and its a.s.sociates are not variable. Their characters are singularly constant, as their limited synonymy and total lack of varietal names attest.

Plate x.x.x.

Fig. 260, Cone. Fig. 261, Leaf-fascicle and magnified leaf-section from a ternate fascicle. Fig. 262, Magnified leaf-section from a binate fascicle. Fig. 263, Multinodal branchlet bearing lateral and subterminal conelets and a ripe cone. Figs. 257, showing mucronate scales of the conelet, and 259, showing dermal tissues of the leaf, are applicable also to this species.

[Ill.u.s.tration: PLATE x.x.x. P. GLABRA (256-259), ECHINATA (260-263), TAEDA (264-267)]

=XII. INSIGNES=

Pits of the ray-cells small. Cones tenaciously persistent, serotinous in various degrees. Conelets mucronate or spinose.

Spring-shoots uninodal.

Resin-ducts mostly internal 48. Pringlei Resin-ducts mostly septal 49. oocarpa Spring-shoots multinodal.

Cones symmetrical.

Leaf-hypoderm not biform.

Bark-formation late 50. halepensis Bark-formation early 51. pinaster Leaf-hypoderm biform.

Cones with slender spines.

Leaves binate.