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bog bird's-foot lotus, bog bird's-foot trefoil, bog deervetch, meadow bird's-foot-trefoil, meadow deervetch, meadow or bog bird's-foot trefoil, pinnate lotus

balsam bird's-foot trefoil, pine lotus, stipulate lotus, thicket lotus

Habit Herbs usually robust, 15–50 cm, glabrous; rhizomatous, rhizomes spongy-thickened, whitish, rooting at nodes. Herbs ± robust, 15–50(–100) cm, usually villous and legume hairy, sometimes glabrous, sometimes glandular-viscid; rhizomatous.
Stems

1–5, usually ascending, sometimes decumbent, unbranched or branched, ± fleshy or not.

1–10+, erect to ascending, unbranched or branched, wiry or fleshy.

Leaves

stipules ovate, 2–5 mm, scarious; petiolate;

rachis straight, 2–7 cm;

leaflets 5–9(–11), petiolulate, blades usually elliptic to obovate, rarely oblanceolate, (7–)10–25 mm, apex emarginate or rounded to obtuse or acute, surfaces glabrous.

stipules widely ovate to lanceolate, (4–)6–9 mm, usually scarious, sometimes leafy, base auriculate or subauriculate; petiolate;

rachis straight, 2–8 cm;

leaflets 9–15(–19), petiolulate to subsessile, blades ovate to obovate, 5–20 mm, apex obtuse to ± acute, surfaces glabrous or hairy, sometimes finely punctate.

Peduncles

ascending, (1–)5–10 cm, longer than subtending leaf, elongating in fruit, glabrous;

bract subtending umbel or absent, 1(–3)-foliolate.

ascending, then spreading, 1–7 cm, shorter than subtending leaf, little elongating in fruit, ± densely hairy, sometimes glandular;

bract medial, (1–)3(–7)-foliolate.

Umbels

4–10-flowered.

4–9(or 10)-flowered.

Flowers

10–15 mm;

calyx reddish, 5.5–7.5 mm, glabrous, tube obconic-cylindric, 4–5 mm, lobes abaxial 3 subulate to lanceolate, adaxial 2 triangular, 1–2 mm, usually eciliate, sometimes sparsely ciliate;

corolla banner and keel yellow, wings white or cream, wings longer than keel, claw longer than calyx tube, banner reflexed to 180°, keel apex subacute.

10–12 mm;

calyx green, purplish, or pink, 5–6.5 mm, ± hairy, sometimes glandular, tube cylindric or obconic-cylindric, 4–5 mm, lobes subulate or short-triangular, 1–1.5(–2) mm, ciliolate or eciliate;

corolla banner and keel purple or pink with pink-veined white tips, wings white, longer than keel, claw ± equaling or slightly longer than calyx tube, banner implicate-ascending, keel apex acute.

Legumes

± ascending to ± inclined, ± reddish to dark brown, linear-oblong, turgid, 30–50(–85) × 1.5–2.5 mm, thinly leathery, incompletely septate, glabrous.

± inclined, olive brown to reddish brown, broadly oblong, turgid, 20–25 × (2–)3–4 mm, thinly leathery, incompletely septate, ± hairy to glabrate.

Seeds

8–20, olive to reddish or dark brown, oblong, 1.5 mm.

5–7, reddish brown, oblong, to 3 mm.

2n

= 14.

Hosackia pinnata

Hosackia stipularis

Phenology Flowering spring–early summer.
Habitat Wet to moist, open areas, springy meadows, bogs, wetlands, springs, streambeds, stream banks, seepages, in water, ditches.
Elevation 30–2500 m. (100–8200 ft.)
Distribution
from FNA
CA; ID; OR; WA; BC
[WildflowerSearch map]
[BONAP county map]
from USDA
California
[WildflowerSearch map]
[BONAP county map]
Discussion

Hosackia pinnata reaches its northern limit near Nanaimo, southeastern Vancouver Island, British Columbia (M. Donovan 2006). It ranges southward along the inner foothills of the coastal ranges (avoiding areas of high precipitation) and in the Cascade Range, to the Coast Ranges of California (to Santa Barbara County) and along the Sierra Nevada. Hosackia pinnata is sometimes disjunct inland to eastern Washington and northwestern Idaho and, rarely, in central Oregon.

Hosackia bicolor Douglas ex Bentham and Lotus bicolor Frye & Rigg are both superfluous, illegitimate names that pertain to H. pinnata.

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

Varieties 2 (2 in the flora).

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

Key
1. Stems fleshy or wiry; stipules narrow to wide, base sometimes subauriculate.
var. stipularis
1. Stems wiry; stipules wide, base auriculate.
var. ottleyi
Source FNA vol. 11. FNA vol. 11.
Parent taxa Fabaceae > subfam. Faboideae > Hosackia Fabaceae > subfam. Faboideae > Hosackia
Sibling taxa
H. alamosana, H. crassifolia, H. gracilis, H. incana, H. oblongifolia, H. rosea, H. stipularis, H. yollabolliensis
H. alamosana, H. crassifolia, H. gracilis, H. incana, H. oblongifolia, H. pinnata, H. rosea, H. yollabolliensis
Subordinate taxa
H. stipularis var. ottleyi, H. stipularis var. stipularis
Synonyms Lotus pinnatus Lotus stipularis
Name authority (Hooker) Abrams in L. Abrams and R. S. Ferris: Ill. Fl. Pacific States 2: 541. (1944) Bentham: Trans. Linn. Soc. London 17: 365. (1836)
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