Astragalus bisulcatus var. haydenianus
Astragalus bisulcatus var. bisulcatus
Hayden's milkvetch
twogrooved milkvetch
(13–)21–35, 5–27 mm.
17–29, (5–)10–25(–32) mm.
35–80-flowered;
axis (4–)5.5–25 cm in fruit;
bracts (2.5–)3–5 mm.
25–75-flowered;
axis 5–18 cm in fruit;
bracts (2–)2.5–7 mm.
8–11 mm;
calyx usually pallid, tube 3.1–4 mm, lobes 1–2.7 mm;
corolla white or whitish to ochroleucous;
banner longer than keel.
13–17.5 mm;
calyx usually red-purple, tube 3.3–5.7 mm, lobes 1.5–4.5(–6) mm;
corolla pink-purple, or pallid and purple- or lilac-tipped or suffused, or white or whitish and keel tip maculate;
banner longer than keel.
ellipsoid or oblong-ellipsoid, (5–)6.5–9.5 × 2–4 mm, transversely rugose-reticulate, strigulose;
stipe 1.4–3 mm.
linear- or narrowly oblong-ellipsoid, (8–)10–17(–20) × 2–4.5 mm, smooth or faintly reticulate, glabrous or strigulose;
stipe 3–5(–6) mm.
5–8.
10–14(or 15).
= 24.
= 22, 24.
Astragalus bisulcatus var. haydenianus
Astragalus bisulcatus var. bisulcatus
Variety haydenianus from the Wasatch Plateau in Utah has been confused by some workers with the similarly pale-flowered var. major, but the flowers are consistently smaller, much more numerous, and the fruits smaller than in var. major.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
Variety bisulcatus has been confused with Astragalus racemosus, with which it sometimes intermingles. The gibbous calyx of A. bisulcatus and two-grooved versus ± three-sided fruit serve to distinguish them. Where they are sympatric, A. bisulcatus is usually purple-flowered. The vars. bisulcatus and haydenianus are known to contain selenium and swainsonine, both poisonous to livestock (S. F. Trelease and O. A. Beath 1949; J. M. Kingsbury 1964).
(Discussion copyrighted by Flora of North America; reprinted with permission.)
SW CO Wildflowers
WildflowerSearch
iNaturalist
USDA Plants Database
KS Wildflowers
PNW Herbaria
