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 ?
These plants also show apical pinnae with bases abruptly attenuate and not as decurrent as the western South America collections (Figs.
Lamellae decurrent, crowed, with two-sized lamellulae, margin even to eroded, concolor with the sides, consistency fleshy to coriaceous, white (1A1), pale grey (1B1) to greenish yellow (1C2).
Ventral leaf base shortly and narrowly decurrent, the decurrent part 1 cell wide ...
The evidence now favours them having been formed through branch abscission, especially since Lindsey (1915) described and illustrated two new specimens of Bothrodendron minutifolium, one showing a short stem bearing a mass of dichotomising leafy shoots that has a clean-cut, trumpet shaped base, the other showing a main axis bearing leafy branches that have similar decurrent, trumpet-shaped bases.
Stem leaves [+ or -] concave, either straight, oblong-ovate with abruptly acute or obtuse and apiculate or rounded apex, or falcate, ovate to oblong-ovate with gradually and shortly to longly acuminate apex; erect-spreading to imbricate, usually complanate; margin plane, entire or slightly denticulate near apex; costa short and double, occasionally absent; median lamina cells linear-flexuose, becoming shorter and wider towards apex and slightly shorter, wider and porose towards base; marginal cells similar or slightly shorter and wider than adjacent median lamina cells; alar cells numerous, hyaline, inflated, forming a well delimited group, slightly or longly decurrent. Branch leaves narrower and smaller than stem leaves or only slightly smaller.
Stem leaves straight, concave, ovate, elongate-ovate or lingulate; [+ or -] erect and imbricate, sometimes spreading; margin plane, slightly recurved at base, entire; apex rounded or obtuse, cucullate; costa long and single (up to 80% of length leaf); median lamina cells linear, slightly incrassate, porose; marginal cells similar or narrower than adjacent median lamina cells; alar cells rectangular, shortly rectangular or quadrate, hyaline, [+ or -] inflated, [+ or -] thick-walled, forming a well delimited ovate or rectangular group along basal leaf margin, decurrent; initial cells of rhizoids abundant near apex or beside nerve in upper part of leaves, rhomboidal and hyaline.
24) oblong, entire, imbricate, decurrent, more or less spreading; costa pronounced, extending to the apex; walls of cells at leaf base thickened; alar cells (Fig.
5) Show the possible consequences of not pruning decurrent trees.
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).