Trifolium repens
Trifolium obtusiflorum
Dutch clover, trèfle blanc, white clover
clammy clover, creek clover
creeping, branched, rooting at nodes.
erect or ascending, branched.
palmate;
stipules lanceolate, 0.9–1.3 cm, margins entire, apex short-subulate;
petiole 5–20 cm;
petiolules to 1 mm;
leaflets 3, blades obovate, obcordate, or orbiculate, 0.6–4 × 0.4–2.5 cm, base cuneate, veins moderately prominent, margins serrulate distally, apex rounded, emarginate, or retuse, surfaces glabrous.
palmate;
stipules ovate, 1–1.5 cm, sheathing, margins deeply lacerate, apex acuminate;
petiole 1.5–10 cm;
petiolules to 0.5 mm;
leaflets 3, blades elliptic, lanceolate, oblanceolate, rhombic, or obovate, 1.5–4 × 0.3–1.7 cm, base cuneate, veins thickened, margins coarsely spinulose-serrate, apex acute, mucronate, surfaces glandular.
axillary, 20–40+-flowered, globose, 1.5–3.5 × 1.5–3.5 cm;
involucres absent.
axillary or terminal, 10–50-flowered, globose or ovoid, 1–3.5 × 1–3 cm;
involucres flattened or bowl-shaped, 3–8 mm, when folded, not hiding flowers except proximally, incised 1/4–1/3 their length.
erect, from prostrate stems, 1.5–30 cm.
3–15 cm, glandular.
strongly reflexed in fruit, elongate, 3–5 mm;
bracteoles white, lanceolate, 1–2 mm.
erect, 1 mm;
bracteoles absent.
8–13 mm;
calyx campanulate, 3–5 mm, glabrous, veins 6–10, tube 1.5–2.5 mm, lobes unequal to subequal, adaxial shorter than tube, triangular-lanceolate, orifice open;
corolla white, often pinkish in age, 4–12 mm, banner ovate-lanceolate or oblong, 4–12 × 1–4 mm, apex rounded.
13–20 mm;
calyx tubular-campanulate, slit between adaxial lobes, 10–13 mm, glandular, veins 20+, tube 5–7 mm, lobes unequal, narrowly triangular or lanceolate-subulate, usually entire, rarely 3-fid or shouldered below apex, orifice open;
corolla white or pale pinkish with dark purple spot, 10–18 mm, banner broadly elliptic, 10–18 × 2–4 mm, apex blunt.
linear-oblong, 4–5 mm.
obovoid, 3.5–4 mm.
3 or 4, yellow, reddish brown, or light brown, ovoid-reniform, 1 mm, smooth, glossy.
1 or 2, brown, mottled, ellipsoid or mitten-shaped, 2.5 mm, smooth.
= 16, 28, 32, 48, 64.
= 16.
Trifolium repens
Trifolium obtusiflorum
Trifolium repens may very well be the most important temperate pasture plant (M. J. Baker and W. M. Williams 1987) and has been considered the most important perennial pasture plant in North America (C. V. Piper 1924). It was introduced at least as early as the mid 1800s (R. N. Mack 2003) and spread so rapidly that it became known to Native Americans as White Man’s Foot Grass (W. Strickland 1801). It is morphologically diverse; most material from the flora area represents var. repens, but some specimens fit within the circumscriptions given by M. Zohary and D. Heller (1984) of var. giganteum Lagrèze-Fossat, with inflorescences to 3.5 cm diameter and leaflets nearly 4 cm; others have smaller, pale-pink petals with hairy petioles and pedicels, and approach var. biasolettii (Steudel & Hochstetter) Ascherson & Graebner (T. occidentale Coombe).
(Discussion copyrighted by Flora of North America; reprinted with permission.)
Trifolium obtusiflorum is much less common than the similar T. willdenovii, occurring in moist areas in cismontane California and north into Oregon (W. L. Jepson [1923–1925]). It is easy to distinguish from T. willdenovii by its glandularity, which causes fresh specimens to be sticky to the touch.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
- Local floras:
BC, 
CA, 
OR, 
WA - Local Web sites: CalFlora, CalPhotos,
Flora NW, 
Go Botany, 
IL Wildflowers, 
KS Wildflowers, 
LA Plants, 
MD Biodiversity, 
MI Flora, 
MN Wildflowers, 
MO Plants, 
PNW Herbaria, 
SW CO Wildflowers, Turner Photog. 
WildflowerSearch
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USDA Plants Database- LBJ Wildflower Center
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