Menyanthes trifoliata L.
Other common names: Bog bean, bog myrtle, bog hop, bog nut, brook bean, bean trefoil, marsh trefoil, water trefoil, bitter trefoil, water shamrock, marsh clover, moonflower, bitterworm.
Habitat and range: The buck bean is a marsh herb occurring in North America as far south as Pennsylvania, Minnesota, and California. It is also native in Europe.
Description: This perennial herb arises from a long, black, creeping, scaly rootstock, the leaves being produced from the end of the same on erect sheathing stems measuring about 2 to 10 inches in height.
The leaves consist of three oblong-oval or broadly oval leaflets 11/2 to 3 inches long, somewhat fleshy and smooth, blunt at the top, with margins entire and narrowed toward the base; the upper surface is pale green and the lower surface somewhat glossy, with the thick midrib light in color.
The flower cluster is produced from May to July on a long, thick, naked stalk arising from the rootstock. It bears from 10 to 20 flowers, each with a funnel-shaped tube terminating in five segments which are pinkish purple or whitish on the outside and whitish and thickly bearded with white hairs within. The capsules which follow are ovate, blunt at the top, smooth and light brown, and contain numerous smooth and shining seeds. Buck bean is a perennial belonging to the buck-bean family (Menyanthaceae).
The leaves are generally collected in spring. They lose more than three-fourths of their weight in drying.
Buck-bean leaves have a very bitter taste, but no odor. Large doses are said to have cathartic and sometimes emetic action, but the principal use of buck-bean leaves is as a bitter tonic. They have been employed in dyspepsia, fevers, rheumatic and skin affections, and also as a remedy against worms.
