The Genus Pinus - Part 18
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Part 18

Western Long Island to central Georgia and north Alabama, and from eastern Tennessee to southern Indiana and southeastern Ohio. It is a low bushy tree in the north, but in the south and west it attains small timber-size and is locally exploited. It is hardy beyond the limits of its natural range, growing readily in the vicinity of Boston. Its short binate leaves, the persistent long p.r.i.c.kles of its cone, and its tough branches, combine to distinguish this Pine from its a.s.sociates. The obvious relationship of P. virginiana and P.

clausa places the former in this, rather than in the preceding group.

Plate x.x.xIII.

Fig. 284, Cones. Fig. 285, Conelet and its enlarged spinose scale.

Fig. 286, Leaf-fascicle, magnified leaf-section and more magnified dermal tissues of the leaf. Fig. 287, Buds.

53. PINUS CLAUSA

1884 P. clausa Vasey ex Sargent, Rep. 10th Cens. U. S. ix. 199.

Spring-shoots multinodal. Bark-formation slow, as in the preceding species. Leaves binate, from 5 to 9 cm. long; resin-ducts medial, or with an occasional internal duct, hypoderm biform when of two rows of cells. Conelets with long tapering acute scales. Cones from 5 to 8 cm.

long, reflexed, ovate-conic, symmetrical, persistent, often serotinous; apophyses l.u.s.trous nut-brown, elevated along a transverse keel, the umbo forming a triangular persistent spine.

A species of limited range, confined to the sandy coast of Alabama and to Florida. It sometimes attains timber-size, but is usually a low spreading tree of no commercial importance and never seen in cultivation. It is recognized by its smooth branches, binate leaves and numerous, often multiserial, cl.u.s.ters of persistent, often closed, cones. It is a.s.sociated with P. caribaea and, in the northern part of its range, it grows with the other Southern species. By its close resemblance it may be considered the serotinous form of P. virginiana.

Plate x.x.xIII.

Fig. 288, Three nodal groups of cones of the same year. Fig. 289, Conelet and its enlarged scale. Fig. 290, Leaf-fascicle and magnified leaf-section. Fig. 291, Larger form of the tree.

[Ill.u.s.tration: PLATE x.x.xIII. P. VIRGINIANA (284-287), CLAUSA (288-291)]

54. PINUS RIGIDA

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

1909 P. serotina Long, in Bartonia, ii. 17 (not Michaux).

Spring-shoots multinodal. Leaves ternate, from 7 to 14 cm. long; resin-ducts medial, or with an occasional internal duct, hypoderm biform. Scales of the conelet abruptly prolonged into a spine. Cones from 3 to 7 cm. long, ovate-conic, symmetrical, persistent, dehiscent at maturity or rarely serotinous; apophyses l.u.s.trous tawny yellow, elevated along a transverse keel, the umbo salient and forming the broad base of a slender sharp p.r.i.c.kle.

A tree with bright green foliage in spreading tufts. The northern limit of its range is in southwestern New Brunswick, southern Maine, central New Hampshire and Vermont, the Thousand Islands of the St.

Lawrence River and central Ohio. It ranges into Pennsylvania and Delaware at low levels and thence over the Alleghanies into northern Georgia. It is a.s.sociated with P. strobus and P. resinosa and, further south, with P. virginiana. The cones are rarely serotinous, but it is remarkably like P. serotina in many characters, and is therefore placed in this group.

Plate x.x.xIV.

Fig. 292, Cones. Fig. 293, Leaf-fascicle, magnified section through a fascicle, and magnified dermal tissues of the leaf. Fig. 294, Upper part of a tree.

55. PINUS SEROTINA

1803 P. serotina Michaux, Fl. Bor. Am. ii. 205.

Spring-shoots multinodal. Leaves ternate, from 12 to 20 cm. long; resin-ducts medial or medial and internal, hypoderm biform. Conelet long-mucronate. Cones from 5 to 7 cm. long, subglobose or short-ovate, symmetrical, persistent, serotinous; apophyses l.u.s.trous tawny yellow, slightly elevated along a transverse keel, the umbo forming the broad base of a slender, rather fragile p.r.i.c.kle.

This species is confined to low wet lands from southeastern Virginia to northern Florida and central Alabama. It is one of the a.s.sociated six timber-Pines of the Southern States and the only one of them with serotinous cones. Its wood is of like value with that of P. taeda, the two species being constantly confused by lumbermen. It is never a.s.sociated with P. rigida, but its resemblance to that Pine is so great that it may be regarded as its serotinous form. Its leaf is longer, its cone usually more orbicular and the p.r.i.c.kle weaker.

Plate x.x.xIV.

Fig. 295, Cone. Fig. 296, Conelet and its enlarged scale. Fig. 297, Leaf-fascicle and magnified leaf-section.

56. PINUS PUNGENS

1803 P. taeda Lambert, Gen. Pin. i. t. 16, (as to cone).

(not Linnaeus).

1806 P. pungens Lambert in Ann. Bot. ii. 198.

1852 P. montana Noll, Bot. Cla.s.s Book, 340. (not Miller).

Spring-shoots multinodal. Leaves binate or ternate, from 3 to 7 cm.

long; resin-ducts medial, or with an occasional internal duct, hypoderm biform. Scales of the conelet much prolonged into a very acute triangle.

Cones from 5 to 9 cm. long, symmetrical or subsymmetrical, tenaciously persistent, serotinous; apophyses l.u.s.trous or subl.u.s.trous fulvous brown, much elevated along a transverse keel, the umbo forming a stout formidable spine, uniform or nearly uniform on all faces of the cone.

A mountain species ranging from central Pennsylvania to northern Georgia, with isolated stations in western New Jersey and Maryland. It is remarkable among the Pines of eastern North America for the size and strength of the spines of its cone. The armature resembles that of the cone of the western P. muricata, but with the difference that the western cone is strongly oblique, the anterior and posterior spines varying greatly in size.

Plate x.x.xIV.

Fig. 298, Cone. Fig. 299, Conelet and its enlarged scale. Fig. 300, Leaf-fascicle and magnified leaf-section.

[Ill.u.s.tration: PLATE x.x.xIV. P. RIGIDA (292-294), SEROTINA (295-297), PUNGENS (298-300)]

57. PINUS BANKSIANA

1803 P. Banksiana Lambert, Gen. Pin. i. 7. t. 3.

1804 P. hudsonia Poiret in Lamarck, Encycl. Meth. v. 339.

1810 P. rupestris Michaux f. Hist. Arbr. Am. i. 49, t. 2.

1811 P. divaricata Dumont de Courset, Bot. Cult. ed. 2, vi. 457.

Spring-shoots multinodal. Leaves binate, from 2 to 4 cm. long; resin-ducts medial, hypoderm biform. Conelets minutely mucronate. Cones from 3 to 5 cm. long, erect, ovate-conic, oblique, much curved or variously warped from the irregular development of the scales, serotinous; apophyses l.u.s.trous tawny yellow, concave, flat or convex, the umbo small and unarmed.

The most northern American Pine, growing near the Arctic Circle in the valley of the Mackenzie River, whence it ranges southeasterly to central Minnesota and the south sh.o.r.e of Lake Michigan, and easterly through the Dominion of Canada to northern Vermont, southern Maine, and Nova Scotia. In the northern part of its range it is the only Pine, but further south it is a.s.sociated with P. strobus and P.

resinosa. It is easily identified by its curious curved or deformed cones.

Plate x.x.xV.

Fig. 301, Cones. Fig. 302, Biserial cones of the same year.

Fig. 303, Leaf-fascicle and magnified leaf-section. Fig. 304, Habit of the tree.

58. PINUS CONTORTA

1833 P. inops Bongard in Mem. Acad. Sci. St. Petersb. ii. 163, (not Aiton).

1838 P. contorta Douglas ex Loudon, Arb. Brit. iv. 2292, f. 2211.

1853 P. Murrayana Balfour in Bot. Exp. Oregon, 2, f.

1854 P. Boursieri Carriere in Rev. Hort. 225, ff. 16, 17.

1868 P. Bolanderi Parlatore in DC. Prodr. xvi-2, 379.