Montana Field Guide

Annual to perennial. Stems prostrate to ascending 10–45 cm. Herbage sparsely villous. Leaflets obovate, 5–15 mm long. Inflorescence 5–10 mm long with 10 to 35 nodding flowers. Flowers yellow, 2–3 mm long; calyx ca. 1.5 mm long. Legume 1-seeded, reniform, becoming black, sparsely glandular-hairy, veiny, 2–3 mm long (Lesica et al. 2012. Manual of Montana Vascular Plants. BRIT Press. Fort Worth, TX).

Black Medic – Medicago lupulina, exotic
* Shallow-rooted annual or short-lived 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. Oblanceolate.

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 mm 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.

Toothed Medic – Medicago polymorpha, exotic
* Taprooted annual plant.
* Flowers: yellow, 4-5 mm long.
* Racemes: with 2-5 flowers.
* 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. broadly oblong, each 1-2 cm long.

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 has elongated ridges (veins) that delimit spaces (areolae), and these 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.

Roadsides, fields, lawns (where it can be a persistent weed), grasslands, woodlands, meadows; plains, valleys (Lesica et al. 2012. Manual of Montana Vascular Plants. BRIT Press. Fort Worth, TX).

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).

Useful Links:
Montana Invasive Species website
Montana Biological Weed Control Coordination Project
Montana Department of Agriculture - Noxious Weeds
Montana Weed Control Association
Montana Weed Control Association Contacts Webpage.
Montana Fish, Wildlife, and Parks - Noxious Weeds
Montana State University Integrated Pest Management Extension
Weed Publications at Montana State University Extension - MontGuides