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panicle false indigo, panicle false indigo or indigo-bush

dark indigo-bush, shining false indigo

Habit Shrubs or suffrutescent herbs, 1–3 m; arising from compact, woody root. Shrubs, 1–2(–3) m; arising from compact, woody root.
Stems

longitudinally grooved and ridged, eglandular, mostly puberulent, canescent, or tomentose, sometimes glabrate.

smooth, usually eglandular, mostly glabrous or puberulent.

Leaves

(10–)20–40 cm;

stipules linear, 2–3 mm, eglandular, pubescent;

petiole (20–)30–60(–90) mm, eglandular, puberulent, canescent, or tomentose;

rachis eglandular, puberulent or canescent;

leaflets (9–)11–19, stipels acicular, 1–2 mm, petiolule (2–)4–10 mm, sparsely gland-dotted, usually pilosulous proximally, glabrous distally, blade narrowly elliptic to oblong or ovate, 15–30(–50) × (14–)18–22(–26) mm, base round, margins flat, entire, apex round, surfaces sparsely gland-dotted abaxially, canescent to tomentose or glabrate abaxially, usually puberulent to glabrate or glabrous adaxially;

veins conspicuous, distinctly raised abaxially;

midvein terminated by a slender mucro, 0.5–1.8 mm.

10–18(–22) cm;

stipules linear to narrowly setaceous, 3–5 mm, sometimes sparsely gland-dotted, short-pilose;

petiole (15–)20–35(–50) mm, eglandular, usually glabrous;

rachis eglandular, usually glabrous;

leaflets (7–)9–15(–19), stipels not seen, petiolule 2–5(–7) mm, eglandular, glabrous or pilosulous, blade drying blackish, usually elliptic to oblong, sometimes ovate, 20–40(–70) × (10–)15–35(–45) mm, base round, margins flat, entire, apex usually emarginate, sometimes round, surfaces distinctly shiny adaxially, usually glabrous and eglandular, rarely sparsely puberulent and sparsely gland-dotted abaxially;

midvein terminated by a slender mucro, 0.1–0.2 mm.

Racemes

(1–)5–12-branched, paniculiform, (5–)15–30(–40) cm;

rachis eglandular, short-pilose;

bracteoles linear, 1–2 mm, eglandular, short-pilose.

1–3(–8)-branched, (5–)8–15(–25) cm;

rachis usually eglandular, usually glabrous, sometimes puberulent;

bracteoles drying blackish, linear to setaceous, 1.5–3(–4) mm, usually eglandular, glabrous or short-pilose.

Pedicels

1–2 mm, eglandular, short-pilose.

drying blackish, 1–2.2 mm, eglandular, glabrous or short-pilose.

Flowers

calyx tube funnelform, 1.8–2.2 mm, distal 1/3 gland-dotted, usually short-pilose, rarely glabrate;

lobes: abaxial lobe linear to narrowly lanceolate, adaxial lobes usually triangular to ovate, (1–)1.2–2 mm;

banner purple, broadly obcordate, 5–7 × 3–4 mm, indistinctly clawed, margins entire or slightly erose;

filaments 5–6 mm, connate basally 2.5–3 mm;

anthers orange;

ovary glabrous.

calyx drying blackish, tube usually funnelform to obconic, rarely campanulate, 2–2.5 mm, usually eglandular, glabrous or short-pilose;

lobes: abaxial lobe triangular, slightly longer, adaxial lobes round to triangular, 0.2–1.4 mm;

banner reddish purple, broadly obovate, 4.5–6 × 3–4.8 mm, obscurely clawed, margins entire or irregularly erose;

filaments 5–7 mm, connate basally 2–2.5 mm;

anthers yellow;

ovary glabrous.

Legumes

sessile, 4–6(–8) × 2–2.5 mm, margins curved outward abaxially, bent outward adaxially, gland-dotted, glabrous.

short-stipitate, 6–8 × 2.5–3.5 mm, margins curved outward abaxially, straight or slightly curved inward adaxially, rarely at least distal 1/3 gland-dotted, glabrous.

Seeds

reddish brown, 3–3.5 × 1.5–1.8 mm, smooth.

not seen.

Amorpha paniculata

Amorpha nitens

Phenology Flowering May–Jun. Flowering Apr–Jun.
Habitat Moist, acid thickets, bogs, and swamps. Moist thickets and woods.
Elevation 10–300 m. (0–1000 ft.) 50–600 m. (200–2000 ft.)
Distribution
from FNA
AR; LA; OK; TX
[BONAP county map]
from FNA
AL; AR; GA; IL; KY; LA; OK; SC; TN
[BONAP county map]
Discussion

Amorpha paniculata is listed as threatened in Arkansas and as a species of concern in Oklahoma.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Amorpha nitens is listed as endangered by the state of Illinois and as a species of special concern in Georgia; it is considered to be a sensitive species in the Shawnee National Forest by the United States Forest Service. Amorpha nitens and A. fruticosa share most of their characters and differ most distinctively by the tendency to blacken upon drying ascribed to A. nitens, although some A. fruticosa individuals can blacken upon drying as well.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Source FNA vol. 11. FNA vol. 11.
Parent taxa Fabaceae > subfam. Faboideae > Amorpha Fabaceae > subfam. Faboideae > Amorpha
Sibling taxa
A. californica, A. canescens, A. confusa, A. crenulata, A. fruticosa, A. georgiana, A. glabra, A. herbacea, A. laevigata, A. nana, A. nitens, A. ouachitensis, A. roemeriana, A. schwerinii
A. californica, A. canescens, A. confusa, A. crenulata, A. fruticosa, A. georgiana, A. glabra, A. herbacea, A. laevigata, A. nana, A. ouachitensis, A. paniculata, A. roemeriana, A. schwerinii
Name authority Torrey & A. Gray: Fl. N. Amer. 1: 306. (1838) F. E. Boynton: Biltmore Bot. Stud. 1: 139. (1902)
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