Menyanthes trifoliata. Buck Bean.
The Buck bean or Marsh Trefoil is one of those plants which are native in Europe and North America, with so little difference of structure, in the two continents, that their specific identity can hardly be doubted. I have compared specimens of the native, and foreign plant, without being able to perceive the least definable difference, except in size; the American being smaller. Yet, if we admit the statements of botanical writers, the plant flowers in England at least a month later than it does in the neighbourhood of Boston, a circumstance not usual in other species of vegetables.
The most spongy and boggy soils, which are inundated at certain seasons, and never wholly destitute of water, are the favorite situations of the Menyanthes trifoliata. It often constitutes large beds at the margin of ponds and brooks. It is common in New England, and grows, according to Pursh, as far south as Virginia.
The genus Menyanthes has its corolla hairy on the upper side; stigma bifid; capsule one celled, two valved. The species in the present article is named from its ternate leaves. Class Pentandria. Order Monogynia. Natural orders Rotaceae, Lin. Gentianae, Juss.
The root of this plant penetrates horizontally in the bog-earth to a great distance. It is regularly intersected with joints at the distance of about half an inch from each other, these joints being formed by the breaking off of the old petioles and their sheaths. The leaves proceed from the end of the root on long stalks furnished with broad sheathing stipules at base. They are trifoliate, nearly oval, glabrous, somewhat fleshy, and slightly repand, or furnished with many irregularities at the edge, which hardly prevent them from being entire. The scape is round, ascending and smooth, bearing a conical raceme of flowers. Peduncles straight, scattered, supported by ovate concave bractes. Calyx erect, subcampanulate, five parted, persistent. Corolla funnel shaped, the tube short, the border five cleft, spreading and at length revolute, clothed on the upper part with a coating of dense, fleshy, obtuse fibres. The colour, in the American variety, is generally white, with a tinge of red, particularly on the outside. Stamens five, shorter than the corolla, and alternate with its segments; the anthers oblong-arrow shaped. Germ ovate; style cylindrical, persistent, as long as the corolla; stigma bifid, compressed. Capsule ovate, two valved, one celled. Seeds numerous, minute, attached to two lateral receptacles.
In New England this plant flowers about the middle of May.
The whole plant and particularly the root has an intensely bitter taste, hardly exceeded by that of Gentian and Columbo. This bitterness resides chiefly in an extractive matter, soluble in water and spirit. The root is, however, resinous and impregnates alcohol more strongly than water, and may be precipitated from its tincture, in part, by the latter fluid.
The root of this vegetable is undoubtedly entitled to a high place in the list of tonics. In Europe it has long been admitted to a place in the Materia Medica, and has received the commendations of various physicians. When given in small doses, about ten grains, it imparts vigour to the stomach and strengthens digestion. Its tincture, moderately used, has the same effect. Large doses, such as a drachm of the powdered root, or two or three gills of the saturated decoction, produce vomiting and purging, and frequently powerful diaphoresis. In this respect it agrees with many vegetable bitters, and perhaps resembles most nearly the Eupatorium perfoliatum. Its bulk, however, and unpleasant taste render it inconvenient to be used as an evacuant.
We are told by authors that the Buck bean has been employed with benefit in intermittent and remittent fevers. Boerhaave, in his own case of gout, was relieved by drinking the juice of the plant mixed with whey. Other physicians have found it useful in keeping off the paroxysms of that complaint. Dr. Cullen informs us, that he has "had several instances of its good effects in some cutaneous diseases of the herpetic or seemingly cancerous kind. It was taken by infusion in the manner of tea." Others have commended this vegetable in rheumatism, dropsy, scurvy and worms. Its reputation in the North of Europe, particularly in Germany, was at one time so high, that it was consumed in large quantities, and deemed a sort of panacea. Its true character, however, is simply that of a powerful bitter tonic, like Gentian and Centaury, to which it is closely related in its botanical habit, as well as sensible properties.
We may regard this plant as one of the numerous vegetable bitters abounding in our country, which are fully equal in strength to imported articles of their class, and which may hereafter lessen our dependance on foreign drugs.
Linnaeus, in his Flora Lapponica, informs us, that in times of scarcity, sheep will subsist upon this plant, notwithstanding its bitterness. The Laplanders employ it as a substitute for hops to prevent acescency in their beer. They even introduce it in some instances into their bread, upon which Linnaeus bestows the epithet, "amaras et detestabilis."
Menyanthes trifoliate, Linn. Sp. pl.
Oeder, Flora Dan. t. 541.
Curtis, Flor. Lond. 4. t. 17.
Woodville, Med. Bot. t. 2.
Smith, Engl. Bot. t.. 495.
Michaux, Flora, i. 125.
Pursh, i. 159.
Menyanthes palustre triphyllum, Ray. Syn. 285.
Trifolium paludosum, Gerard, em. 1194.
Murray, Apparatus med. ii. 33.
Linnaeus, Fl. Lap. 50.
Haller, Hist. Stirp. Helv. 633.
Cullen, Mat. Med. ii. 53.
Thompson, Lond. Disp. 256.