Northern Prairie Wildlife Research Center
Aquatic and Wetland Vascular Plants of the Northern Great Plains
28. Fabaceae, the Bean Family
1. Amorpha L.
1. Amorpha fruticosa L. -- False indigo
Branching shrub mostly 1-3 m tall; twigs tan to gray. Leaves once-pinnate,
the blade oblong, 6-16 cm long; leaflets 9-27, elliptic to obovate, 1-4
cm long, 4-28 mm wide, glabrous above, puberulent and sometimes punctate beneath,
on petiolules 1-3 mm long; petioles 2-5 cm long; stipules none. Inflorescence
of 2-several, terminal, dense, spikelike racemes, these 2-15 cm long, the raceme
axis and pedicels puberulent; bracts lanceolate, shorter than the calyx,
pubescent, deciduous; pedicels 1-2 mm long. Flowers dark purple,
irregular; calyx campanulate, unequally and shallowly 5-toothed, 1.5-3
mm long, often glandular, the lowest tooth somewhat longer and narrower than
the others; corolla 1-lobed, only the standard present, folded to enclose
the stamens, 3-5 mm long; stamens 10, the filaments united near the base.
Fruits indehiscent, oblong, curved upward, 5-7 mm long, strongly glandular,
1- to 2-seeded. Flowering Jun, fruiting late Jul--Sep. Wet meadows, stream banks,
shores, ditches and floodplains; frequent from e and c ND through NE; (PA to
Sask., s to AL and n Mex.).
Return to Family -- Fabaceae - The
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