Melilotus albus |
Melilotus wolgicus |
|
---|---|---|
honey-clover, white melilot, white sweet-clover |
sweetclover, volga sweet-clover |
|
Habit | Herbs usually biennial, rarely annual, 30–150(–260) cm. | Herbs biennial, 40–120(–150) cm. |
Stems | erect or ascending. |
erect. |
Leaves | stipules lanceolate-subulate to setaceous, 4–6(–10) mm, margins usually entire, sometimes toothed at base; leaflet blades narrowly oblong-obovate to suborbiculate-oblong, 10–24(–50) × 5–12(–15) mm, margins dentate. |
stipules linear-setaceous or subulate, 6–8(–10) mm, margins entire; leaflet blades rhombic-ovate to oblong-lanceolate, or linear, 10–30 × 2–8 mm, margins dentate or entire. |
Racemes | 40–80(–120)-flowered. |
25–60-flowered. |
Pedicels | 1–1.5(–2) mm. |
2–4 mm. |
Flowers | 3.5–5(–6) mm; corolla white; ovary glabrous. |
3–3.5 mm; corolla white; ovary glabrous. |
Legumes | obovoid, subglobose, or globose-ovoid, 3–5 mm, reticulate-veined, glabrous. |
obovoid, 4–5 mm, distinctly reticulate-veined, glabrous. |
Seeds | 1 or 2(or 3), ovoid, (1.7–)2–2.5(–3.5) mm. |
usually 1 (or 2), oblong-ovoid, 2.5 mm. |
2n | = 16. |
= 16 [Eurasia]. |
Melilotus albus |
Melilotus wolgicus |
|
Phenology | Flowering spring–fall. | Flowering spring–summer. |
Habitat | Grasslands, mixed forests, canyons, streamsides, riverbeds, lakeshores, waste places, roadsides. | Gravel pits, wasteland, drainage ditches, sandy banks. |
Elevation | 0–2700 m. (0–8900 ft.) | 200–500 m. (700–1600 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; NL; NS; NT; NU; ON; PE; QC; SK; YT; SPM; Greenland; Eurasia [Introduced in North America; introduced also in Mexico, West Indies, South America, Australia]
|
MB; SK; Eurasia [Introduced in North America] |
Discussion | Melilotus albus is extremely variable in Eurasia, and has been divided into many infraspecific taxa. It is the most important economic species in Melilotus, often grown as a crop, green manure, and honey plant, and posing a widespread weed problem. Essentially all white-petaled Melilotus plants growing outside of cultivation in North America are M. albus; herbarium specimens often do not show the color well, sometimes resulting in misidentification, particularly between M. albus and M. officinalis. Aside from petal color, the species are quite similar. The venation areolae on the mature pods tend to differ: the raised venation ridges tend to form an irregular reticulation on the mature fruits of M. albus; they tend to form transverse areolae on the fruits of M. officinalis (S. J. Darbyshire and E. Small 2018). Although M. albus and M. officinalis are sometimes merged, there are very strong barriers to interbreeding between the two (G. T. Webster 1955; M. Maekawa et al. 1991), in addition to geographical and ecological differences, which justify their continued recognition as separate species. P. Coulot and P. Rabaute (2013) included Melilotus albus in Trigonella sulcata (Desfontaines) Coulot & Rabaute (treated here as M. sulcatus). Most botanical literature incorrectly lists the authority for Melilotus albus as Desrousseaux in Lamarck instead of Medikus. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
The Manitoba vouchers of Melilotus wolgicus are mostly G. A. Stevenson collections at DAO from the Brandon area and are almost certainly established escapes from the extensive experimental cultivation of Melilotus species by Stevenson; it has also been observed persisting in the forage plot area of the Research Station, Saskatoon, Saskatchewan, but does not appear to have spread elsewhere. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 11. | FNA vol. 11. |
Parent taxa | Fabaceae > subfam. Faboideae > Melilotus | Fabaceae > subfam. Faboideae > Melilotus |
Sibling taxa | ||
Name authority | Medikus: Vorles. Churpfälz. Phys.-Ökon. Ges. 2: 382. (1787) — (as alba) | Poiret in J. Lamarck et al.: Encycl., suppl. 3: 648. (1814) — (as wolgica) |
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