BugwoodWiki Article

yellow sweet-clover
Melilotus officinalis (L.) Lam.

Overview

Appearance
Melilotus alba is an annual to biennial herb that can grow from 3-8 ft. (0.9-2.4 m) tall.
Foliage
Leaves are alternate, trifoliate with petioles up to 1 in. (2.5 cm) long. Leaflets are greyish green, 1 in. (2.5 cm) long and 0.3 in. (0.85 cm) wide, dentate, and oblong to ovate.
Flowers
Racemes are 2-6 in. (5.1-15.2 cm) long. Flowers are small, floppy, tubular at base becoming broader toward outer edges, 0.3 in. (0.85 cm) long with 5 petals. Blooming occurs from summer through fall.
Fruit
Seed pods are smooth or slightly reticulated, 0.3 in. (0.85 cm) long, terminates in a beak, and contains 1 or 2 seeds.
Ecological Threat
Melilotus alba can be found in prairies, fields, vacant lots, along roadsides, and in waste lands. It is native to Europe and Asia.

General Description:

Melilotus spp. are monocarpic, annual or biennial herbs of the legume family (Leguminosae), sweet-scented, with alternate, pinnately three-foliate leaves. The flowers are perfect and much like those of Trifolium and Medicago, but in small, slender spike-like racemes with a deciduous corolla, free from the filaments. The legume is ovoid, leathery and wrinkled, longer than the calyx, and scarcely dehiscent, with one or two seeds.

M. alba (also known as M. albus) has an erect, branched, glabrous or glabrate stem, 1-3 m high, with serrated, narrowly obovate to oblong leaflets that are truncate or emarginate. It is the only white-flowered sweetclover in the Midwest and Great Plains. The corolla is 4-5 mm long; the fruit is 3-4 mm long and somewhat reticulate.

M. officinalis is similar in height and appearance to M. alba, the distinguishing feature being the two yellow corolla. The leaflets are closely serrate, obovate-oblong and obtuse. The corolla is 5-6 mm long; the fruit, 2.5-3.5 mm long, glabrous or glabrate and prominently reticulate.

Yellow-flowered M. altissima and M. indica can usually be told from M. officinalis by their height and distribution. M. altissima is found from British Columbia to Nova Scotia, is very tall (1.6 m) and can be distinguished from M. officinalis by its pubescent ovaries and pods. M. indica is abundant in the South and Pacific states and grows to just .5 m. Its flowers are smaller and more densely packed in the raceme than those of M. officinalis. Sweetclover seedlings closely resemble those of alfalfa (Medicago spp.). Melilotus may be distinguished from alfalfa by the absence of pubescence on the underside of the leaves and by its bitter taste. Anna Kummer's Weed Seedlings (1951, University of Chicago Press) may be helpful in distinguishing Melilotus seedlings from those of other similar legumes.

Resources

Selected Images


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yellow sweet-clover
Melilotus officinalis
Plant(s)
Steve Dewey
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yellow sweet-clover
Melilotus officinalis
Plant(s)
University of Alaska - Anchorage Archive
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yellow sweet-clover
Melilotus officinalis
Plant(s)
Dave Powell
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yellow sweet-clover
Melilotus officinalis
Flower(s)
Jamie Nielsen
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yellow sweet-clover
Melilotus officinalis
Foliage
Steve Dewey
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yellow sweet-clover
Melilotus officinalis
Foliage
Karan A. Rawlins
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yellow sweet-clover
Melilotus officinalis
Fruit(s)
Pedro Tenorio-Lezama
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yellow sweet-clover
Melilotus officinalis
Flower(s)
Jamie Nielsen
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yellow sweet-clover
Melilotus officinalis
Plant(s)
Wendy VanDyk Evans
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yellow sweet-clover
Melilotus officinalis
Flower(s)
Bonnie Million
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yellow sweet-clover
Melilotus officinalis
Flower(s)
Steve Dewey
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yellow sweet-clover
Melilotus officinalis
Fruit(s)
Mary Ellen (Mel) Harte
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yellow sweet-clover
Melilotus officinalis
Fruit(s)
Steve Dewey
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Melilotus officinalis
Foliage
Chris Evans
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yellow sweet-clover
Melilotus officinalis
Flower(s)
Chris Evans
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yellow sweet-clover
Melilotus officinalis
Plant(s)
Mary Ellen (Mel) Harte
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yellow sweet-clover
Melilotus officinalis
Infestation
Michael Shephard
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yellow sweet-clover
Melilotus officinalis
Infestation
Steve Dewey
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yellow sweet-clover
Melilotus officinalis
Infestation
Steve Dewey
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yellow sweet-clover
Melilotus officinalis
Seed(s)
D. Walters and C. Southwick
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yellow sweet-clover
Melilotus officinalis
Seed(s)
D. Walters and C. Southwick

Maps


EDDMapS Distribution - This map is incomplete and is based only on current site and county level reports made by experts, herbaria, and literature. For more information, visit www.eddmaps.org

EDDMapS Distribution

State Regulated List - This map identifies those states that list this species on their regulated list. For more information, visit Invasive.org

State Regulated List

Taxonomic Rank

Kingdom: Plantae
Phylum: Magnoliophyta
Class: Magnoliopsida
Subclass: Rosidae
Order: Fabales
Family: Fabaceae (Leguminosae)
Genus: Melilotus

Other System Links

Plants: MEOF
Bayer: MEUOF
GRIN: 24009
ITIS: 26150
NPDN Pest: PCQBJBD
NPDN Host: 36529

Synonyms and Other Names

Other Common Names:
white sweetclover, yellow sweetclover, sweetclover

Related Scientific Names:

Melilotus album Medikus(Synonym)

Categories

Category: Forbs/Herbs