Trifolium bifidum |
Trifolium polyodon |
|
---|---|---|
notch-leaf clover, Pinole clover, piñole clover |
Pacific grove clover, woods or Pacific grove clover |
|
Habit | Herbs annual, 5–55 cm, sparsely pubescent or glabrous. | Herbs annual, 10–60 cm, glabrous. |
Stems | erect, branched. |
decumbent or ascending, branched. |
Leaves | palmate; stipules ovate to lanceolate, 0.8–1.5 cm, margins entire or slightly serrate, apex acicular; petiole 1–7 cm; petiolules to 0.5 mm; leaflets 3, blades narrowly obcordate, obovate, oblanceolate, or linear, 1–2.5 × 0.3–0.7 cm, base cuneate, veins moderately thickened, margins serrate distally or entire, apex rounded, truncate, shallowly to deeply retuse, or deeply 2-fid, surfaces glabrous or hairy abaxially along midvein. |
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. |
Inflorescences | axillary or terminal, 5–30-flowered, globose to subglobose, 0.8–1.5 × 0.8–1.5 cm, rachis prolonged beyond flowers; involucres a very narrow rim, to 0.5 mm. |
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. |
Peduncles | 3–8 cm. |
1–2 cm. |
Pedicels | reflexed in fruit, 1–3 mm; bracteoles broadly triangular, membranous, to 0.5 mm. |
straight, to 1 mm; bracteoles absent. |
Flowers | 6–8 mm; calyx campanulate, 3–3.6 mm, slightly hairy or glabrous, veins 10, tube 1–1.5 mm, lobes unequal, subulate, margins green or purple, orifice open; corolla pink or purple, 5–7 mm, banner elliptic to oblong, 5–7 × 3–4 mm, apex rounded, apiculate. |
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. |
Legumes | stipitate, obovoid, 3–4 mm. |
ellipsoid, 3.5–4 mm. |
Seeds | 1 or 2, brown, mottled, oblong, 2–3 mm, smooth. |
2, dark brown, mottled, ovoid or reniform, 1.7–1.9 mm, smooth. |
2n | = 16. |
|
Trifolium bifidum |
Trifolium polyodon |
|
Phenology | Flowering Apr–Jun. | Flowering Apr–Jun. |
Habitat | Open woodlands, fields, roadsides, slopes, stream margins, meadows. | Along streams, moist meadows. |
Elevation | 0–1200 m. (0–3900 ft.) | 0–150 m. (0–500 ft.) |
Distribution |
CA; OR; WA; BC; Mexico (Baja California)
|
CA |
Discussion | Trifolium bifidum ranges from Baja California, Mexico, northward through California to scattered sites in Oregon, Washington, and British Columbia. Recent re-evaluation of Trifolium bifidum and related species showed complete overlap in characters for the two varieties that have been recognized previously, with no clear distinctions between them (L. Rogers, pers. comm.). (Discussion copyrighted by Flora of North America; reprinted with permission.) |
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.) |
Source | FNA vol. 11. | FNA vol. 11. |
Parent taxa | Fabaceae > subfam. Faboideae > Trifolium | Fabaceae > subfam. Faboideae > Trifolium |
Sibling taxa | ||
Synonyms | T. bifidum var. decipiens, T. greenei, T. hallii | T. tridentatum var. polyodon |
Name authority | A. Gray: Proc. Calif. Acad. Sci. 3: 102. (1864) | Greene: Pittonia 3: 215. (1897) |
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