Trifolium macrocephalum |
Trifolium alexandrinum |
|
---|---|---|
big-head clover, large-head clover |
Egyptian clover |
|
Habit | Herbs perennial, 5–25 cm, villous. | Herbs annual, 20–60 cm, appressed-pubescent. |
Stems | erect or ascending, branched. |
erect, branched. |
Leaves | palmate; stipules ovate, obovate, or oblong, 1–3 cm, margins entire, irregularly lobed, or serrate, apex acute or acuminate; petiole 1–14 cm; petiolules 0.9–1.2 mm; leaflets (5–)7–9, blades broadly to narrowly obovate, often folded, 1–2.7 × 0.4–1.1 cm, base cuneate, veins thickened, especially distally, margins serrulate, apex rounded or truncate, apiculate, surfaces villous abaxially, sparsely villous to glabrate adaxially. |
palmate; stipules lanceolate, 1–2 cm, margins denticulate distally, plumose-ciliate, apex caudate; petiole 1–8 cm; petiolules 1+ mm; leaflets 3, blades broadly elliptic to oblong, 1–5 × 0.5–1.5 cm, base cuneate, veins fine, margins denticulate, apex usually mucronate, sometimes retuse, surfaces hairy. |
Inflorescences | terminal, 20–32-flowered, globose or ovoid-ellipsoid, 2.5–8 × 3–7 cm; involucres absent. |
terminal, 25–100-flowered, ovoid, elongate in fruit, 1–2.5 × 1–1.5 cm; involucres minute or absent. |
Peduncles | 2–8 cm. |
0.5–9 cm. |
Pedicels | erect, 1–1.5 mm; bracteoles broadly ovate, membranous, to 0.5 mm, truncate. |
absent; bracteoles absent. |
Flowers | 20–30 mm; calyx campanulate, 10–22 mm, villous, veins 10–15, tube 2.5–4 mm, lobes subequal, subulate, plumose, orifice open; corolla white, creamy white, or pinkish, keel petals deep pink, 20–28 mm, banner ovate or oblong, 20–28 × 10–13 mm, apex rounded or slightly emarginate. |
13–16 mm; calyx cylindric (campanulate in fruit), 6–8 mm, appressed-hairy, veins 10, tube 1–2 mm, lobes erect to slightly spreading, equal or abaxial 2 slightly longer, narrowly triangular, orifice open, hairy; corolla cream or yellowish white, 13–16 mm, banner narrowly spatulate, 13–16 × 3–4 mm, apex obtuse. |
Legumes | ovoid, 4–5 mm. |
ellipsoid, leathery distally, transversely dehiscent, 2.2–2.5 mm. |
Seeds | 1 or 2, yellow or reddish, mitten-shaped to ellipsoid, 2.5–3 mm, smooth. |
1, yellow, ovoid, 2–2.2 mm, smooth, glossy. |
2n | = 32, 48. |
= 16. |
Trifolium macrocephalum |
Trifolium alexandrinum |
|
Phenology | Flowering Apr–Jun. | Flowering Apr–May. |
Habitat | Rocky places, hard, compacted clay-gumbo, lava beds, sage-covered slopes, full sun. | Disturbed areas, fields. |
Elevation | 80–2500 m. [260–8200 ft.] | 0–50 m. [0–160 ft.] |
Distribution |
CA; ID; NV; OR; WA
|
CA; w Asia (Syria) [Introduced in North America; introduced also in e Asia (e China), n Africa, Australia] |
Discussion | Trifolium macrocephalum has the largest inflorescences of any clover. Trifolium megacephalum Nuttall (1818) is an illegitimate replacement name for Lupinaster macrocephalum Pursh. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Trifolium alexandrinum (known also as berseem, from its Arabic name) has been cultivated in the Mediterranean region for millennia and appears to have been introduced into Egypt in the sixth century (P. B. Kennedy and W. W. Mackie 1925). The origin of T. alexandrinum was long shrouded in mystery, because it appeared that the progenitors of the species were possibly extinct (W. E. Knight 1985b). Examination of similar species using molecular data gave indications that T. berytheum Boissier & C. I. Blanche and T. salmoneum Mouterde might be the primary ancestors from which domestication occurred through artificial selection in Syria (A. Badr et al. 2008). (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 11. | FNA vol. 11. |
Parent taxa | ||
Sibling taxa | ||
Synonyms | Lupinaster macrocephalum | |
Name authority | (Pursh) Poiret in J. Lamarck et al.: Encycl., suppl. 5: 336. (1817) | Linnaeus: Cent. Pl. I, 25. (1755) |
Web links |