Cladrastis

Taxonomy

Cladrastis C.S. Rafinesque-Schmaltz Cincinnati Lit. Gaz. 1: 60. 21 Feb 1824.

Subfamily: Faboideae.
Phylogenetic Number: 3.2.41.
Tribe: Sophoreae.
Group: Sophora.
Species Studied - Species in Genus: 5 studied; 5 in genus, or 6 in genus.

Description

Fruit: A legume; unilocular; 3.8–9.5 cm long; 0.8–1.3 cm wide; 1.8–2.7 cm thick; 2–9 times longer than wide; with persistent androecial sheath, or deciduous androecial sheath; with deciduous corolla; with persistent calyx, or deciduous calyx; with calyx shorter than fruit; without orifice formed by curving of fruit or fruit segments; straight; not plicate; not twisted; symmetrical; fusiform to linear; not inflated; flattened; with beak; straight, or hooked; with solid beak the same color and texture as fruit; long tapered at apex, or tapered at apex; aligned with longitudinal axis of fruit; tapered at base, or rounded at base; aligned with longitudinal axis of fruit; with the apex and base uniform in texture; chartaceous; seed chambers externally invisible; margin constricted, or not constricted; margin slightly constricted along both margins; margin without sulcus; margin plain, or embellished; margin with thickened sutural areas, or wing(s); wing(s) present, or absent; wing(s) 2; wing(s) 1–2 mm wide; wing(s) sutural; wing(s) on both sutures; substipitate, or nonstipitate; with the stipe 2–8 mm long; with all layers dehiscing (in literature), or indehiscent. Replum invisible. Epicarp dull; monochrome, or multicolored; mottled; yellow to brown; with brown overlay; mottling color combination variable; with surface texture uniform; glabrous, or pubescent and indurate; with hairs erect; with 1 type of pubescence; sparsely strigose; with pubescence golden; with pubescence uniformly distributed; with simple hairs; stiff; with hair bases plain; eglandular; without spines; not smooth; with elevated features; veined, or not veined; reticulately veined; not tuberculate; slightly wrinkled; not exfoliating; without cracks; without embedded tissue, much thicker than epicarp, running from base to apex. Mesocarp present; thin; surface not veined; 1-layered; without balsamic vesicles; without reniform canals; solid; chartaceous. Endocarp present; visible; dull; opaque; monochrome; brown to yellow; smooth, or smooth and floury-filamentous; without adhering pieces of testa; nonseptate; chartaceous; not exfoliating; remaining fused to mesocarp and epicarp; with wing(s) extending into epicarp, or without wings; entire. Seed(s) 1–7; length oblique to fruit length; neither overlapping nor touching; in 1 series. Funiculus ca. 2 mm long; of 1 length only; partially filiform and partially thick; convoluted. Aril present; dry; when dry rim-aril; fimbriate; cream.

Seed: 5–10 mm long; 3–5 mm wide; 1.8–3 mm thick; not overgrown; not angular; asymmetrical; elliptic to irregular; compressed; with surface smooth; without visible radicle and cotyledon lobes; without hilar sinus; without umbo on seed faces; without medial ridge on each face. Cuticle not exfoliating; not inflated; not wrinkled. Testa present; without pieces of adhering epicarp; not adhering to endocarp; free from endocarp; dull; not modified by a bloom; colored; monochrome; brown to reddish brown; glabrous; smooth; chartaceous. Pleurogram absent. Pseudopleurogram absent. Fracture lines absent. Rim absent. Wing(s) absent. Raphe visible; from hilum through lens to base of seed and terminating; not bifurcating; darker than testa; brown; flush. Hilum present; visible; with faboid split; with the lips of the faboid split the same color as the rest of the hilum; larger than punctiform; 1–1.5 mm long; with curved outline; circular, or elliptic; apical according to radicle tip but marginal according to seed length; recessed; within corona; corona color darker than testa. Lens discernible; 1–1.5 mm long; with margins straight; diamond-shaped; not in groove of raphe; adjacent to hilum; 1–2 mm from hilum; mounded; similar color as testa; darker than testa; brown; not within corona, halo, or rim. Endosperm present; thick; not pluglike and not resembling tip of radicle; covering entire embryo; adnate to testa, or embryo. Cotyledons not smooth; sulcate; both outer faces convex; both the same thickness; both more or less of equal length; not folded; margin entire 180 degrees from base of radicle; similar at apex; partially concealing radicle, or not concealing radicle; entire over radicle; without lobes; with the interface division terminating at base of radicle; without margins recessed; tan; inner face flat; glabrous on inner face. Embryonic axis oblique; parallel to length of seed; without a joint evident between the radicle and the cotyledons. Radicle differentiated from cotyledon; linear; lobe tip straight, or curved; oblique to cotyledons; centered between cotyledons; less than 1/2 length of cotyledons. Plumule rudimentary; glabrous.

Distribution

North America (1 sp.) and eastern Asia (4 or 5 spp.).

New World and Old World; United States; Japan and China.

Worldwide crop (as an ornamental in temperate areas of United States, Japan, and China).

Generic Notes

Robertson (1977) discussed the cultivation and morphology of Cladrastis.

Tribal Notes

Tribe Sophoreae

Polhill (1981b) stated that the Sophoreae s.l. is a tribe of convenience between the Caesalpinioideae and the bulk of the Papilionoideae, sharply defined from neither. He transferred four genera from Sophoreae into the Swartzieae (1), Amburana (3.1.15), Ateleia (3.1.13), Cyathostegia (3.1.14), and Holocalyx (3.1.12), following Herendeen's (1995) cladistic analyses. Herendeen performed cladistic analyses for all Swartzieae genera, sensu Cowan (1981), 19 Sophoreae genera, and three Caesalpinioideae genera. He concluded that Swartzieae is polyphyletic and that it should be disbanded and its genera transferred to Sophoreae. Preliminary rbcL data (Doyle et al. 1997) supported his conclusions.