Senna hebecarpa

Cassia hebecarpa var. longipila E. L. Braun, Rhodora 42: 49. 1940.—". . . Knott County, Kentucky, July 23, 1937, Braun Ky. no. 1633 . . —Holotypus, GH!—Equated with C. hebecarpa by Isely, 1975, p. 99.

Senna Mimosae foliis siliqua hirsuta Dillenius, Hort. Eltham. 351, t. 260, fig. 339 (optima!). 1732 & 1774.—Erroneously referred by Linnaeus (1753) to Cassia marilandica and not differentiated from it until 1904 (Shafer, l.c. infra).

Cassia marilandica sensu Bentham, 1871 et auct. post-Linnaean. omn. usque ann. 1904, ex parte; sensu Shafer, Torreya 4: 178, fig. 1 (a-d). 1904, where first accurately defined, but under the wrong name; sensu House, Wild Fls New York pi. 104. 1918. Ditremexa marilandica sensu Britton & Rose, 1930, p. 257, quoad descr., basionym, exclus.

Cassia hebecarpa sensu Fernald, 1950, p. 885; Gleason, 1952, p. 384 + fig.; Wilbur, 1963, p. 25, fig. 6; Rickett, Wild Fls U.S. 2: 320, pl. 116. 1967; Isely, 1975, p. 99, map 40.

Closely resembling S. marilandica in habit, stature and foliage, different (constantly or potentially) as described following: pubescence of short appressed or incurved hairs lacking, the stems, lf-stalks (especially proximally) and sometimes the axes of inflorescence and fl-buds usually thinly setose with fine straight patent bristles up to 0.8-1.8(-2.2) mm and the ovary commonly shaggy-pilose, but the setae variable in length and density, occasionally 0, the plant then at anthesis simulating S. marilandica and reliably distinguished only by ovule-number.

Stipules linear or linear-attenuate 3.5-9 x 0.3-1 mm, bristly-ciliolate, minutely ciliolate, or glabrous.

Major lvs 13-23 cm; petiole including pulvinus (3-)4-7(-8) cm; gland (exceptionally a pair) situated next to pulvinus or at a point on petiole up to 8(-11) mm distant from stem, most commonly shortly stipitate and either slenderly or plumply claviform obtuse or minutely apiculate, but sometimes sessile obovoid, rarely subcylindroid, in profile 1.2-3.3 x 0.6-1.8 mm; lfts 6-9(-10) pairs, a little decrescent toward proximal or toward both ends of rachis, elliptic, oblong- or lance- elliptic, rarely elliptic-oblanceolate or narrowly ovate, ±3-6 x 1-2 cm, 2.5-3.5 times as long as wide, at apex either obtuse or deltately acute, mucronate.

Racemes up to 25(-37)-fld, the axis including peduncle 1-5.5(-7) cm; pedicels (11-) 13-20(-22) mm; perianth on average a trifle smaller than that of S. marilandica, the outer sepals 3.7-5 mm, the inner ones 5-7 mm, the longer petals 8-12 mm; androecium and style of S. marilandica; ovary commonly shaggy-hirsute with spreading, partly wavy or spirally twisted hairs up to 1-2 mm, but sometimes only shortly strigulose-pilosulous; ovules 10-16(-17).

Body of pod piano-compressed (6-)7-11.5 x 0.55-0.8 cm, when ripe brunnescent or nigrescent, thinly bristly-hirsute or less often remotely strigulose or glabrate, the papery valves shallowly sulcate at the interseminal septa, these very narrow and 5-8 mm apart, the rhombic or nearly square locules thus about as long as wide; seeds obliquely descending across their locule, in outline broadly ovate or bluntly rhombic, (3.5-)4.3-5.3 x 3.5-4.5 mm, strongly compressed parallel to the valves, the testa dull ochraceous or fulvous sometimes castaneous- or livid-tinged, crackled when dry, the narrowly or broadly ovate areole 2-3.3 x (0.9-) 1.1-1.7 mm.—Collections: 121.—Fig. 10 (androecium), 14 (pod, seed).

Habitats of S. marilandica but said to tolerate lighter, more porous soils, local but widespread over n.-e. and e.-centr. United States, barely entering s. Canada: s. Wisconsin and Illinois to s. Michigan, s. Ontario and New England (n. to Connecticut valley in s. Maine and New Hampshire), s.-e. and s. to e. Tennessee, upland North and South Carolina (and perhaps adjacent Georgia), reaching the Coastal Plain in s.-e. New York (Long I.) and Delaware.—Fl. VII-IX.