No. 80. Ranunculus acris.

No. 80. Ranunculus acris. Names. Acrid Crowfoot.
Fr. Renoncule acre.
Vulgar. Buttercups, Yellow Weed, Blister Weed, Pilewort, Burwort, Meadowbloom, Yellows, &c.

Classif. Nat. Order of Ranunculaceous. Polyandria polygynia L.

Genus RANUNCULUS. Calyx five leaved. Five petals, with a scale or pit at the base. Many stamina. Many pistils and seeds, united in a head.
Sp. Ranunculus acris. L. Pubescent, stem multiflore, erect, branched; leaves triparted, segments laciniate acute, upper ones linear; peduncles not sulcated, calyx spreading, hairy.

Description. Root fibrose, fasciculate, perennial. Stem two feet high, with many branches and flowers, terete, pubescent, erect. Leaves alternate, petiolate, broadly triparted, pubescent, segments broad lanceolate, with many unequal gashes, all acute; the upper leaves almost sessile, with three linear entire segments. Flowers corymbose, large and yellow, peduncles unequal, not furrowed. Calyx with five spreading folioles, hairy, oval, obtuse. Petals rounded, entire. Seeds in a globose head.

History. An extensive genus; nearly all the species have similar active properties, except R. auricomus, R. lanuginosus, R. flammula, R. aquatilis, and a few others which are mild and not acrid. The R. sceleratus, R. bulbosus, R. repens, R. fascicularis, R. pennsylvanicus, &c. are chiefly used with us; the two first, as well as R. acris, are supposed to have been imported from Europe with grass seeds, but now grow abundantly in our meadows and pastures, which they adorn with yellow blossoms in the spring. Although very acrid when fresh, they become mild by drying, and do not spoil the hay, becoming harmless to cattle, who avoid them carefully when growing. Sheep and goats, however, eat the R. acris, and hogs like the roots of R. bulbosus. The mild kinds are liked by cattle, and cows fed on them give good milk. The R. sceleratus is very similar to R. acris, but with smooth leaves and grooved peduncles. The R. bulbosus is easily known by its bulbous root, and the R. fascicularis by a bundle of fleshy roots. They are common all over the United States.

Properties. The whole plant, but chiefly the roots, of all those species, are of a burning, acrid, and corrosive taste when fresh. They act on the skin as rubefacient and escharotics. These properties were known very anciently, and they were used for common blisters before Spanish flies became in general use. The acrid principle, like that of Arum, is volatile, and disappears by the application of heat or even desication, but may be preserved by distillation: the distilled water being very acrid, and holding in solution a peculiar substance, Acroide, which crystallizes, is inflammable, and hardly soluble in any menstruum. The acrimony of these plants is so powerful that it inflames and corrodes the lips and tongue of men and cattle, acts as a violent sternutatory, and if swallowed, they bring on great pain, heat, inflammation of the stomach, and even death. Applied to the skin, they produce redness, erosion, and ulceration, but little pain: the beggars in Europe employ them to produce ugly sores and ulcers, which are neither painful nor dangerous, in order to excite compassion. When used for blisters, they operate in half an hour, and never cause strangury like cantharides. They however act very differently on different individuals, sometimes mildly and beneficially, sometimes violently, producing deep and bad ulcers, difficult to heal. To prevent the effect from spreading, the blister must be applied through a perforation in an adhesive plaster. Like the poison of the Rhus, it has hardly any effect on some individuals, while in others it spreads fast, inflames the parts, and even causes gangrene. They have, however, often been used as external stimulants, in rheumatism, hip disease, sciatica, piles, hemicrania, fixed pains, &etc;c.; when applied to the scalp for hemicrania, it tumifies the hair without breaking the skin. A singular practice once existed in Europe, to cure intermittent fevers by applying them to the wrists or hands. They are useful to destroy warts, corns, and wens. In veterinary, they are employed to cure the fistulous ulcers, and biles on the back of horses. Although very dangerous internally, the distilled water has been used as an instantaneous emetic, equivalent to sulphate of zinc, mustard, and pepper. Also as a powerful but uncertain vermifuge. Henry mentions that the decoction thrown on the ground, makes the ground worms used in angling, come out of it.

Schoepf says, that R. abortivus is diaphoretic, and used in syphilis along with Lobelia. The R. auricomus and other mild species are eaten in Europe as sallad, and all the worst species, even R. sceleratus, as greens, losing all the acrid property by coction (And yet the decoction retains all the acridity? Ho hum. -Henriette). Children are fond of gathering and playing with the blossoms; but this practice may be attended with some danger.


Medical Flora, or Manual of the Medical Botany of the United States of North America, Vol. 2, 1830, was written by C. S. Rafinesque.