white sweet clover

not listed

NNA - Not applicable

SNA - Not applicable

not listed

White sweet clover is listed as an invasive terrestrial plant by the Minnesota Department of Natural Resources. However, it is not currently regulated in Minnesota.

FACU - Facultative upland

FACU - Facultative upland

FACU - Facultative upland

White sweet clover is a 1′ to 8′ tall, erect, freely branching, biennial forb with a strong taproot. The stems are light green and hairless. The taller plants tend to be bushy, the shorter plants lanky. In the first year they are small and do not flower. In the second year they are taller, bushy, and produce many flower clusters.

The compound leaves are alternate, hairless and divided into three leaflets.The leaflets are oblanceolate or obovate, ½″ to 1″ long and up to ¼″ wide. They are grayish-green, finely toothed along the middle and upper margins, the teeth pointed outward rather than forward. The middle leaflet is on a distinct stalk.

The inflorescence is many tall, spike-like clusters of stalked flowers. The clusters are on elongated stems produced in the axils of the middle and upper leaves. The flowering stems are 2″ to 6″ long. Dozens of small flowers are crowded along the top two thirds of the stem.

The flowers are ⅛″ to ⅓″ long and are attached to the stem with a minute stalk. They droop down but ascend at the tip.

1′ to 8′

White

Yellow sweet clover (Melilotus officinalis) has yellow flowers. It is usually a little shorter than white sweet clover. The foliage is plain green, not grayish-green. It blooms 2 to 3 weeks earlier than white sweet clover.

Disturbed sites, roadsides.

May to September

Sources

4, 5, 7, 22, 28, 29, 30.

Native to Asia, Europe, and the Indian subcontinent. Introduced and naturalized in North America.

Common

Some sources, including BONAP and USDA PLANTS, consider white sweet clover (Melilotus alba) and yellow sweet clover (Melilotus officinalis) the same species with differently colored flowers. It that is the case, then white sweet clover should be treated as Melilotus officinalis ssp. alba. BONAP lists Melilotus officinalis but not Melilotus alba. It does not list subspecies or varieties of any plants. USDA PLANTS curiously lists just sweetclover (Melilotus officinalis), with no subspecies, and with Melilotus alba as a synonym. Most sources treat white and yellow sweet clovers as separate species.

Inflorescence

Flowers