decurrent


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Related to decurrent: excurrent

de·cur·rent

(dē-kŭr'ĕnt),
Extending downward.
[L. de-curro, pp. -cursus, to run down]

decurrent

(of plant structures) having the base of an organ extended down its axis; for example, a decurrent leaf has the blade continued downwards as a wing along the PETIOLE.

de·cur·rent

(dē-kŭr'ĕnt)
Extending downward.
[L. de-curro, pp. -cursus, to run down]
References in periodicals archive ?
9-3 cm wide, elliptical or narrowly ovate, cuneate to rounded and sometimes short-decurrent at base, flat or slightly revolute at margin, abruptly short-acuminate or obtuse and apiculate at apex, glabrous or bearing a few short appressed hairs abaxially near base, bearing 2 large raised glands on abaxial surface at base and occasionally 1 or 2 additional glands on abaxial surface above base, the glands rarely on decurrent laminar tissue and appearing to be on apex of petiole, the principal lateral veins 4-6 on each side of midrib; petiole of larger leaves 7-14 mm long, very sparsely sericeous to soon glabrate, eglandular except for glands on decurrent lamina (see above); stipules 0.
2) [micro]m wide x 60-120(130) long, becoming shorter and wider towards apex and slightly shorter, wider and porose towards base; marginal cells similar to adjacent median lamina cells; alar cells rectangular to shortly rectangular, hyaline, strongly inflated, thin-walled, forming a very well delimited group, triangular or [+ or -] quadrate, usually excavate and decurrent.
0 [micro]m long, thin-walled, becoming wider beside costa, shorter, wider and more flexuose towards apex, shorter, wider, thick-walled and porose towards base; marginal cells narrower than adjacent median lamina cells; alar cells rectangular, hyaline, inflated, thin-walled, forming a very well defined group, triangular, usually not reaching the costa (up to 70-90% of distance from leaf margin to costa), strongly excavate and broadly decurrent, transition from alar cells to surrounding cells abrupt; initial cells of rhizoids very common in the upper third of leaves and beside costa, rhomboidal and hyaline.
Baldcypress, sweet gum, black gum, fir, spruce, pine, and other conical-shaped trees with an excurrent growth habit usually require less structural pruning than trees with a decurrent growth habit (Figure 2-1).
Major branches 3-6, more or less erect, somewhat flattened, cream-colored below, beige or tan upward; branching dichotomous to sympodial throughout; branches in 4-7 ranks, more or less erect, substrict, beige or tan, flattened; hymenium unilateral, sterile areas decurrent from axils; internodes diminishing gradually upward; axils rounded; apices awl-shaped to dichotomous, paler than branches ("chamois" to bone white at tips; 4B4).
Others have flattened scale leaves, such as the arbor-vitaes (Thuja, Cupressaceae) and the false cypresses (Chamaecyparis, Cupressaceae) or small awl-shaped leaves with a decurrent base, such as the sugi or Japanese red cedar (Cryptomeria japonica, Taxodiaceae).
2 cm, fleshy, glabrous on both surfaces, venation obscure especially on the upper surface, formed by a midvein and two pairs of pinnate secondary veins, base decurrent, apex obtuse.
We have presented the proportion covering the aerial parts of tree species respectively as excurrent crown and decurrent crown for Common Cypresses and old Rubber trees [9].
Pore surface bright yellow to yellowish brownish upon bruising adnate to decurrent pores rounded toangular 12 per mm tubes shorter near margins of pileus.
Leaves are alternate, sessile, scale-like, entire, sometimes decurrent, from slightly auriculate to amplexicaul or even vaginate, glabrous, mostly with salt-secreting glands.