Classif. Nat. Ord. of Rhodoracea. Decandria monogynia L.
Genus KALMIA. Cal. five parted, corolla hypocrateriform, five lobed, with ten cavities, ten stamina, anthers lodged in the cavities, one pistil, style, and stigma, capsule five celled, many seeded.
Sp. Kalmia latifolia. L. Leaves clustered, petiolate, oval lanceolate, acute, entire: corymbs terminal, viscid, and pubescent.
Description. A shrub, four to ten feet high. Leaves evergreen, thick, coriacious, very smooth, lucid above, pale beneath, entire, acute at both ends, on short petioles, and growing at the end of the branches in clusters. Flowers very handsome, in terminal compound corymbs, trichotome, pubescent viscid, with small subulate tracteas. Flowers large, corolla of a rose colour, tube short, limbus like a cup, with five short acute lobes, ten long staminas, lodging their antlers in the ten cavities of the corolla.
History. A beautiful genus of evergreen shrubs, peculiar to North America, dedicated to Kalm, a Swedish traveller and botanist; several species belong to it, all highly valued in gardens as ornamental: this is the largest and most splendid. Their vernal blossoms are beautiful, but scentless. The K. latifolia grows all over the mountains and hills of the United States. It produces many varieties, such as 1. Alba, all the flowers white. 2. Maculata, with purple spots. 3. Ternata, with ternate leaves. 4. Acuminata. 5. Ovatifolia, 6. Arborea, &c.
It has been by many deemed poisonous to men and cattle. It is certainly deleterious to horses, calves, and sheep feeding on it in winter, because indigestible to them. Sheep, if not soon relieved by oil, will swell and die. Yet deer and goats feed on the leaves, and can digest them. The American partridge, feeding on the buds in the winter, is said by some to become deleterious as food. Bees collect honey on the flowers. The wood is soft when fresh, but becomes hard and dense, nearly similar to box, much used for tools, instruments, and spoons. The Kalmia grows very slow, and lives a century or more.
All the species of this genus having equal properties, ought to be slightly mentioned.
2. K. angustifolia, or Sheep Laurel. Leaves ternate, oblong, obtuse, rusty beneath.
3. K. glauca, or Swamp Laurel. Leaves opposite, oblong, glaucous beneath.
4. K. rosmarinifolia. Leaves opposite, linear, revolute, green beneath.
5. K. cuneata. Leaves scattered, sessile, caneate, oblong, pubescent beneath. In Carolina, &c.
6. K. hirsuta. Hairy, leaves opposite and alternate, lanceolate, flowers axillary, solitary. Southern States.
Properties. Narcotic, errhine, antisiphylitic, antiherpetic, &c. Rather dangerous internally, if it be true that the Indians killed themselves by a strong decoction of it. More useful externally; powdered leaves employed in tinea capitis, and in some fevers: with lard, they form a good ointment for herpes. Bigelow found in them tannin, resin, and mucilage only, yet Thomas asserts its narcotic qualities, and that the decoction even in small doses, produced vertigo, which Bigelow is inclined to disbelieve. Elliot states that the negroes of Carolina use the K. angustifolia and K. hirsuta in a strong wash to cure the itch of men and dogs; it smarts, but cures effectually. It has also been used in psora and other cutaneous affections. It is stated to have been used in syphilis, but how is not told, probably in sores and ulcers. The brown powder of the leaves and seeds, are errhine. Their tincture is powerful and dangeroifc: a few drops killed a rattle snake.
Medical Flora, or Manual of the Medical Botany of the United States of North America, Vol. 2, 1830, was written by C. S. Rafinesque.