Hosackia pinnata
Hosackia oblongifolia
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
narrow leaf lotus, streambank bird's-foot trefoil
1–5, usually ascending, sometimes decumbent, unbranched or branched, ± fleshy or not.
1–30+, decumbent to ascending, unbranched, not fleshy.
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 ovate to lanceolate, 2.5–5 mm, scarious, fragile; short- to (proximally) long-petiolate;
rachis often curved, 1–2.5(–3) cm;
leaflets 3–11, petiolulate, blades usually elliptic to obovate, sometimes lanceolate, 10–25 mm, apex usually acute, sometimes obtuse (often proximally), surfaces appressed-hairy to hirsute or glabrous.
ascending, (1–)5–10 cm, longer than subtending leaf, elongating in fruit, glabrous;
bract subtending umbel or absent, 1(–3)-foliolate.
ascending, (1–)5–10(–12) cm, longer than subtending leaf, elongating in fruit, ± appressed-hairy;
bract subtending umbel or absent, 1–3-foliolate.
4–10-flowered.
1–6-flowered.
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.
8–13 mm;
calyx green, 3.5–6.5 mm, hairy, tube cylindric, 2.5–3.5 mm, lobes subulate, 1–3 mm, ciliolate;
corolla whitish yellow or banner yellow, ± red-veined or reddish, and wings and keel white, keel apex yellow, wings ± equaling keel, claw ± equaling to slightly longer than calyx tube, banner implicate-ascending, keel apex subacute.
± ascending to ± inclined, ± reddish to dark brown, linear-oblong, turgid, 30–50(–85) × 1.5–2.5 mm, thinly leathery, incompletely septate, glabrous.
± ascending to ± inclined, brown, oblong, turgid, 25–50 × 1.5–2 mm, leathery, not septate, glabrous.
8–20, olive to reddish or dark brown, oblong, 1.5 mm.
(6–)8–15(–21), olive to reddish brown, oblong, 1.5–2 mm.
= 14.
= 14.
Hosackia pinnata
Hosackia oblongifolia
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.)
1. Leaflets 7–11, blade surfaces hairy or glabrous; flowers 9–13 mm; ovules 9–15(–21). | var. oblongifolia |
1. Leaflets 3–7, blade surfaces glabrous; flowers 8–9 mm; ovules 5–8. | var. cuprea |
- Local floras:
BC, 
CA, 
OR, 
WA - Local Web sites: CalFlora, CalPhotos,
Flora NW, 
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USDA Plants Database- LBJ Wildflower Center
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