Deep-rooted perennial. Stems ascending, 30–80 cm. Herbage glabrate to sparsely villous. Leaflets oblanceolate, 1–3 cm long. Inflorescence 1–5 cm long with 10 to 40 flowers. Flowers purple or white, 7–12 mm long; calyx 4–7 mm long; sepals longer than the tube. Legume circular in 2 to 3 spirals, 3–5 mm wide, veiny, sparsely villous (
Lesica et al. 2012. Manual of Montana Vascular Plants. BRIT Press. Fort Worth, TX).
Alfalfa –
Medicago sativa, exotic
* Deep-rooted perennial plant.
* Flowers: purple or white, at least 6 mm long.
* Racemes: less than 3 cm long.
* Fruits (legume): surface texture is veiny; coiled or curved with more than one seed.
* Leaflets: 3. Margins serrated in upper half of leaflet. Oblanceolate. 2-4 cm long.
Yellow Alfalfa –
Medicago falcata, exotic
* Deep-rooted perennial plant.
* Flowers: yellow, at least 6 mm long.
* Racemes: 1-2 cm long.
* Fruits (legume): linear to elliptic; surface texture is glabrous; curved, but not coiled; 6-10 mm wide.
* Leaflets: 3. Margins serrated in upper half of leaflet. Oblanceolate, 2-4 cm long.
Black Medick –
Medicago lupulina, exotic
* Shallow-rooted annual or short-livered perennial plant.
* Flowers: yellow, 2-5 mm long.
* Racemes: 5-10 mm long.
* Leaflets: obovate, each 5-15 mm long
* Fruits (legume): kidney shaped (reniform), veiny surface, 2-3 mm long, 1-seeded and black
* Leaflets: 3. Margins serrated in upper half of leaflet.
Toothed Medic –
Medicago polymorpha, exotic
* Taprooted annual plant.
* Flowers: yellow, 4-5 mm long.
* Racemes: with 2-5 flowers.
* Leaflets: broadly oblong, each 1-2 cm long
* Fruits (legume): circular in 2-7 coils, straight to hooked spiny surface, 4-8 mm long.
* Leaflets: 3. Margins serrated in upper half of leaflet.
Yellow Sweetclover –
Melilotus officinalis* Flowers: yellow.
* Racemes: greater than 4 cm long. At peak flowering racemes are 6 times as long as wide.
* Leaflets: 3. Margins serrated more than half-way to the base. Leaflets usually no more than 2 times longer than broad.
* Fruits (legume): surface is of elongated ridges (veins) that delimit spaces (areolae); spaces tend to be longer than wide.
White Sweetclover –
Melilotus albus, exotic
* Flowers: white.
* Racemes: greater than 4 cm long. At peak flowering racemes are 8-15 times as long as wide.
* Leaflets: 3. Margins serrated more than half-way to the base. Leaflets 2.5-3.5 times as long as broad.
* Fruits (legume): surface has shorter ridges (veins) that delimit spaces (areolae), and these spaces tend to be as long as wide.
* Habitat: In Montana there is a tendency for White Sweetclover to grow more commonly in riparian areas and in slightly moister sites.
POLLINATORS The following animal species have been reported as pollinators of this plant species or its genus where their geographic ranges overlap:
Bombus vagans,
Bombus appositus,
Bombus borealis,
Bombus fervidus,
Bombus huntii,
Bombus nevadensis,
Bombus rufocinctus,
Bombus ternarius,
Bombus terricola,
Bombus occidentalis,
Bombus pensylvanicus,
Bombus bimaculatus,
Bombus griseocollis, and
Bombus impatiens (Hobbs 1968, Thorp et al. 1983, Mayer et al. 2000, Colla and Dumesh 2010, Koch et al. 2012, Williams et al. 2014).
