Trifolium polyodon
Trifolium trichocalyx
Pacific grove clover, woods or Pacific grove clover
Monterey clover
decumbent or ascending, branched.
prostrate, decumbent, or erect, branched.
palmate;
stipules lanceolate to ovate, 0.4–1.8 cm, margins lacerate, apex acute to acuminate;
petiole 0.5–6 cm;
petiolules to 1 mm;
leaflets 3, blades broadly elliptic to broadly obovate, 0.4–2.5 × 0.4–1.5 cm, base cuneate, veins moderately thickened, margins dentate-serrulate, apex rounded or truncate, often retuse, surfaces glabrous.
palmate;
stipules ovate, 0.4–1.2 cm, margins serrate-lacerate, apex acuminate;
petiole 1–4 cm;
petiolules 0.5 mm;
leaflets 3, blades obovate, 0.5–1.5 × 0.4–1 cm, base cuneate, veins moderately prominent, margins denticulate, apex truncate, retuse, or mucronulate, surfaces glabrescent.
axillary, 10–25-flowered, subglobose or globose, 1–1.8 × 1–1.8 cm;
involucres flattened or bowl-shaped, 4–7 mm, incised 1/2 their length, when folded, not hiding flowers except proximally, lobes 5–12, dentate-lacerate, spinulose.
axillary or terminal, 2–15-flowered, subglobose, 1.5–1.8 × 0.5–1.5 cm;
involucres flattened or vase-shaped, 1–3 mm, when folded, not hiding flowers except proximally, incised 2/3–3/4 their length, lobes 5–15, linear-lanceolate, entire, acuminate.
1–2 cm.
1.5–4 cm.
straight, to 1 mm;
bracteoles absent.
erect, 1.5 mm;
bracteoles absent.
8–10 mm;
calyx campanulate-tubular, not slit between adaxial lobes, 5–7 mm, glabrous, veins 20, tube 1.9–2.4 mm, lobes unequal, 3-fid or laciniate, often appearing 7+-lobed, orifice open;
corolla pink or pale purple, 8–9 mm, banner elliptic, 8–9 × 2–3 mm, apex retuse.
8–11 mm;
calyx campanulate-tubular, not slit between adaxial lobes, 6–9 mm, usually densely pubescent, rarely sparsely so, veins 10, tube 2.5–4.5 mm, lobes unequal, lanceolate-subulate, orifice open;
corolla light purple with darker purple keel petals, 6–10 mm, banner narrowly obovate, 4–5 × 1 mm, apex retuse.
ellipsoid, 3.5–4 mm.
sessile, oblong, 5 mm.
2, dark brown, mottled, ovoid or reniform, 1.7–1.9 mm, smooth.
3–6(–9), pale brown, mottled purple, globose to mitten-shaped, 0.8–1 mm, smooth to slightly roughened, semiglossy.
Trifolium polyodon
Trifolium trichocalyx
The taxonomic status of Trifolium polyodon, known only from Monterey County, has long been debated. W. L. Jepson (1936) considered it a variety of T. tridentatum Lindley (= T. willdenovii). The first to consider it as a variety of T. variegatum was J. S. Martin (1943), who never formally published a new combination; an invalid combination was made by M. Zohary and D. Heller (1984). D. Isely (1998) included it in his interpretation of T. variegatum as phase 5 of that species; he speculated that T. polyodon might have originated as a hybrid of T. variegatum and T. willdenovii. Molecular studies (N. W. Ellison et al. 2006) showed that T. polyodon is closely related to T. variegatum but is distinct; it also appears to be related to T. cyathiferum.
(Discussion copyrighted by Flora of North America; reprinted with permission.)
Trifolium trichocalyx is an extremely rare species known only from Mendocino and Monterey counties. D. I. Axelrod (1982) suggested that T. trichocalyx might have originated as a hybrid between T. microcephalum and T. variegatum, but this is not supported by molecular studies (N. W. Ellison et al. 2006). It appears to be fire-adapted and appeared in large numbers shortly after a fire in 1987 (U.S. Fish and Wildlife Service 2004).
(Discussion copyrighted by Flora of North America; reprinted with permission.)
CA
WildflowerSearch
iNaturalist
USDA Plants Database
