Pinus Patula - Description

Description

The tree grows to 40 m tall and 100 cm dbh, usually with a single, straight, slender trunk; in closed canopy stands, the depth of the conical or domed crown is ca. 33%. The Bark on young trees is thin, scaly, red-brown, with age becoming thick, dark grey-brown, rough and scaly with large elongated plates and deep longitudinal fissures. First-order branches are long, slender, spreading or slightly ascending; higher order branches are slender, drooping, the ultimate branches pendent. The shoots are rough and scaly when the leaf fascicles have fallen, yellow- to red-brown, foliage shoots with prominent, decurrent pulvini. Cataphylls subulate, recurved at apex, scarious, with erose-ciliate margins, brown, early deciduous. Vegetative buds oblong to cylindrical, the terminal bud 15–20 mm long, the laterals shorter, brown, not resinous; the scales spreading, subulate, ciliate at margins. Fascicle sheaths initially 20–30 mm long with 6-8 imbricate, chartaceous, white-yellow to orange-brown scales, persistent but shortening to 12–15 mm in mature fascicles, slowly weathering to grey-brown. Leaves in fascicles of 3-4(-5), in drooping tufts, typically in two rows on either side of the upturned shoot, persisting 2–3 years, thin, lax, drooping to pendent, (11-)15-25(-30) cm × 0.7-0.9(-1) mm, serrulate at the margins, acute, pale green to dark green. Stomata on all faces of the leaves, in 4-6(-7) lines on the convex abaxial face and 2-3(4) lines on each adaxial face. The leaves are triangular in cross section, the hypodermis usually with a double layer of cells; resin ducts (1-)2-3(4), medial, occasionally 1 internal, stele oval in cross section; outer walls of endodermal cells not thickened; vascular bundles 2, distinct, the xylem strands often connate. Pollen cones crowded near the proximal end of new shoots, spreading, subtended by scarious bracts, ovoid-oblong to cylindrical, 15-20 × 5–6 mm, pink-yellow, turning yellow-brown. Seed cones subterminal or lateral, in whorls of 2 to many, rarely solitary, persistent or deciduous, on short or moderately long (to 20 mm) peduncles. Immature cones ovoid, on short or long recurved peduncles with persistent cataphylls, purple turning light brown, maturing in two seasons. Mature cones narrowly ovoid when closed, usually slightly curved, more or less asymmetrical at base, 5-10(-12) × (3-)4-6.5 cm when open. Seed scales 100-150, serotinous or parting some time after maturing, tenacious or deciduous with the peduncle, (thin) woody, oblong, usually curved when spreading, the proximal scales connate, purple-brown to dark brown, with adaxial light brown marks left by seed wings. Apophysis nearly flat to slightly raised, transversely keeled, more or less gibbous on the proximal scales, more so on one side of the cone, rhombic, upper margin acute or obtuse-rounded, abaxial surface striate or smooth, (lustrous) ochraceous or yellow-brown. Umbo dorsal, flat or raised, often sunken into the apophysis, 3–7 mm wide, grey, with a minute, deciduous prickle. Seeds obliquely ovoid, flattened, 4-6 × 2–4 mm, dark gray. Seed wings articulate, held to the seed by two oblique claws which partly cover the seed on one side, obliquely ovate-oblong, 12-18 × 5–8 mm, light brown with dark stripes (Farjon and Styles 1997).

Read more about this topic:  Pinus Patula

Famous quotes containing the word description:

    Do not require a description of the countries towards which you sail. The description does not describe them to you, and to- morrow you arrive there, and know them by inhabiting them.
    Ralph Waldo Emerson (1803–1882)

    Everything to which we concede existence is a posit from the standpoint of a description of the theory-building process, and simultaneously real from the standpoint of the theory that is being built. Nor let us look down on the standpoint of the theory as make-believe; for we can never do better than occupy the standpoint of some theory or other, the best we can muster at the time.
    Willard Van Orman Quine (b. 1908)