Medicago lupulina |
Medicago sativa |
|||||||||
---|---|---|---|---|---|---|---|---|---|---|
black medic, black medick, hop clover |
alfalfa, lucerne, purple medick |
|||||||||
Habit | Herbs: shoots glabrescent to densely pubescent, hairs eglandular, appressed, sometimes glandular. | Herbs: shoots glabrescent to pubescent, hairs eglandular [glandular]. | ||||||||
Stems | prostrate, decumbent, or semi-erect. |
prostrate to erect. |
||||||||
Leaflets | blades elliptic, ovate, or obovate, 10–20 × 6–15 mm, margins serrate on distal 1/2. |
blades obovate to linear or oblanceolate, 5–35 × 2–15 mm, margins serrate distally. |
||||||||
Inflorescences | (5–)15–50-flowered, cylindrical heads. |
3–30(–50)-flowered, racemes. |
||||||||
Flowers | 2–4 mm; calyx pubescent, hairs eglandular or glandular, lobes equal to tube; corolla yellow, 2 times length of calyx. |
5–15 mm; calyx glabrous or pubescent, hairs eglandular or glandular, lobes equal to tube; corolla usually purple, yellow, or variegated yellow-violet, rarely violet, green, or white, [yellow-orange, pink], 2 times length of calyx. |
||||||||
Legumes | ± ovoid, 2–3.5 × 1 mm, covered with eglandular hairs, sometimes also gland-tipped hairs when young; face with somewhat fusing, prominent veins sometimes appearing as ridges from ventral suture obliquely to dorsal suture. |
curved or with 1.5–6 coils, falcate when curved, lenticular, ovoid, or cylindrical when coiled, 7–15 × 1.5–3 mm when falcate, 4–14 × 3–9 mm when coiled, glabrescent or pubescent with eglandular and/or glandular hairs; face veins (when coiled) oblique from ventral suture, slightly branched, fusing towards dorsal suture. |
||||||||
Seeds | 1, yellow to olive green, oval to reniform, 1.5–2 × 1–1.15 mm. |
2–12, yellow, brownish, greenish yellow, or violet-brown, reniform, 1–2.5 × 1–1.5 mm. |
||||||||
Stipules | margins entire or irregularly toothed. |
margins entire or basally toothed. |
||||||||
2n | = 16, 32. |
= 16, 32. |
||||||||
Medicago lupulina |
Medicago sativa |
|||||||||
Phenology | Flowering spring–fall. | |||||||||
Habitat | Lawns, riverbanks, disturbed areas, roadsides, often on slopes and meadows, railway embankments, wastelands. | |||||||||
Elevation | 0–3000 m. (0–9800 ft.) | |||||||||
Distribution |
AK; AL; AR; AZ; CA; CO; CT; DC; DE; FL; GA; IA; ID; IL; IN; KS; KY; LA; MA; MD; ME; MI; MN; MO; MS; MT; NC; ND; NE; NH; NJ; NM; NV; NY; OH; OK; OR; PA; RI; SC; SD; TN; TX; UT; VA; VT; WA; WI; WV; WY; AB; BC; MB; NB; NF; NS; NT; ON; PE; QC; SK; YT; SPM; Mexico; Asia; Greenland; Europe; n Africa [Introduced in North America; introduced also nearly worldwide in temperate and tropical regions]
|
n Mexico; Eurasia [Introduced in North America; introduced also in West Indies, Central America, South America (Argentina, Brazil, Chile, Uruguay), Pacific Islands, Australia]
|
||||||||
Discussion | Medicago lupulina is valued as a pasture plant (there are several cultivars), cover crop, and as a green manure plant; it is typically plowed under in the fall as part of a crop rotation. Although M. lupulina is often considered a lawn weed, nitrogen fixation associated with this plant contributes to lawn health. Medicago lupulina is a variable species, but the variation is not structured in ways that can reasonably be classified formally. Of the many criteria that have been used to delimit infraspecific groups, presence of gland-tipped hairs and whether annual/biennial or perennial have been most frequently employed. Density of glandular trichomes is highly variable in the species (L. R. Goertzen and E. Small 1993), and taxa such as M. lupulina var. glandulosa Neilreich have no merit. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Subspecies 6 (3, including 1 hybrid, in the flora). Medicago sativa is the most widely grown of the temperate forage legumes. Wherever it is cultivated, escapes are likely to be found in the vicinity, and the species has become established in most countries. This polymorphic Old World species is complicated by polyploidy, hybridization, and domestication and has been divided by some (E. Small 2011) into several species (dozens, by some Russian taxonomists) and innumerable infraspecific taxa. The natural habitats of the wild progenitors of M. sativa in Asia (mostly in the former U.S.S.R.) are rapidly being decimated, and there is considerable danger that valuable genetic diversity is being lost. According to the literature cited below, the three subspecies in the flora region should be expected in all provinces and territories of Canada, and in all states. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
||||||||
Key |
|
|||||||||
Source | FNA vol. 11. | FNA vol. 11. | ||||||||
Parent taxa | Fabaceae > subfam. Faboideae > Medicago > sect. Lupularia | Fabaceae > subfam. Faboideae > Medicago > sect. Medicago | ||||||||
Sibling taxa | ||||||||||
Subordinate taxa | ||||||||||
Name authority | Linnaeus: Sp. Pl. 2: 779. (1753) | Linnaeus: Sp. Pl. 2: 778. (1753) | ||||||||
Web links |
|
|