The fruit of Rhus glabra, Linné.
COMMON NAMES: Smooth sumach, Upland sumach, Pennsylvania sumach.
ILLUSTRATION: Willdenow, Sp. Plant, I, 1478.
Botanical Source.—Great care is necessary in the selection of the several species of Rhus, as many of them are extremely poisonous. Rhus glabra, or Smooth sumach, is a shrub 6 to 15 feet high, consisting of many straggling, glabrous branches, with a pale-gray bark, having occasionally a reddish tint. The leaves are alternate, odd-pinnate, of from 6 to 15 leaflets, about 3 inches long and one-fourth as wide, lanceolate, acuminate, acutely serrate, smooth, shining, and green above, whitish beneath, and sessile, except sometimes the terminal odd one; during the fall they become red. Flowers greenish-red, in terminal, thyrsoid, dense panicles. Calyx of 3 sepals, united at base; petals 5; stamens 5, inserted into the edge or between the lobes of a flattened disk in the bottom of the calyx; styles 3; stigmas capitate. The fruit is a small red drupe, hanging in clusters, and, when ripe, is covered with a crimson down, which is extremely sour to the taste, owing to the presence of malic acid in combination with calcium (W.—G.).
History and Description.—Rhus glabra, sometimes called Upland or Pennsylvania sumach, is common to the United States and Canada, growing in thickets and waste grounds, and on rocky or barren soil, flowering in June and July, and maturing its fruit in September and October. The drupes or berries only are official. They should be gathered before the rains have removed their external downy efflorescence, for when this is washed off the berries are no longer acid. The bark is likewise used to some extent in medicine. The berries are officially described as "subglobular, about 3 Mm. (1/8 inch) in diameter, drupaceous, crimson, densely hairy, containing a roundish-oblong, smooth putamen; inodorous; taste acidulous"—(U. S. P.).
Sumach leaves have been used in tanning, and a concentrated decoction of the bark is used as a mordant for dyeing red colors. Sumach root bark is of a light-gray color, with a tinge of red externally, yellowish-white internally, and of a very astringent and slightly sweet taste. When broken on the plant, a milky fluid exudes from the bark as well as from the leaves, which subsequently forms a solid, gum-like body. Both the bark of the branches and root are used. Both the bark and berries of sumach yield their active properties to water. The excrescences (galls) which form upon the leaves are reddish-brown externally, grayish-white internally, varying in size and appearance, being usually very irregular in their outline, hollow, and sometimes consist of a mere shell, of a line or less in thickness. Their taste is slightly bitter, and very astringent.
Chemical Composition.—Sumach berries have an agreeably acid, slightly styptic taste, which is due, according to W. J. Watson, to malic acid and tannic acids, beside which they contain malate of calcium, gallic acid, fixed and volatile oils, red coloring matter, etc. The bark of the root contains albumen, gum, starch, tannic and gallic acids, caoutchouc, soft resin, coloring matter, and probably a volatile odorous principle (Amer. Jour. Pharm., 1853, p. 193). The leaves of Rhus glabra, collected in Iowa, contained, according to Jos. A. Palen (ibid., 1888, p. 389), about 16 percent of tannin. Virginia-grown leaves usually yield 20 to 25 percent. The excrescences upon the leaves contain tannic and gallic acids, albuminous and coloring matter, and are fully equal to nutgalls in medicinal power. Prof. Trimble (The Tannins) found one specimen to contain 61.7 per cent of tannin.
Action, Medical Uses, and Dosage.—Sumach bark is tonic, astringent, antiseptic, and decidedly alterative; the berries are refrigerant and diuretic. In decoction or syrup, the bark of the root has been found valuable in gonorrhoea, leucorrhoea, diarrhoea, dysentery, hectic fever, scrofula, and in profuse perspiration from debility. Combined with the barks of slippery elm and white pine, in decoction, and taken freely, it is said to have proved highly beneficial in syphilitic ulcerations. Externally, the bark of the root in powder, applied as a poultice to old ulcers, forms an excellent antiseptic. A decoction may also be used in injection for prolapsus uteri and ani, and leucorrhoea, and as a wash in many cutaneous diseases; simmered in lard it is valuable in scald head. A decoction of the inner bark of the root is serviceable in the sore mouth resulting from mercurial salivation, and was formerly much used internally in mercurial diseases. A saturated tincture is useful in ulcerative stomatitis, and for spongy gums attending purpura hemorrhagica and scorbutus. Diarrhoea and dysentery, with intestinal ulceration, seem to be well controlled by it. Dose of the tincture, from 5 to 20 drops. The berries may be used in infusion in diabetes, strangury, bowel complaints, febrile diseases (as a pleasant acidulous drink where acids are indicated), etc., as a gargle in quinsy and ulcerations of the mouth and throat; and as a wash for ringworm, tetter, offensive ulcers, etc. Excrescences are frequently formed on the leaves of this plant, and which are very astringent; when powdered and mixed, with lard or linseed oil, they are said to prove useful in hemorrhoids. In hot weather, if the bark be punctured, a gummy substance flows out, which has been used with advantage in gonorrhoea and gleet, and several urinary affections. Dose of the decoction of sumach bark, or infusion of the berries, from 1 to 4 fluid ounces. A free use of the bark will produce catharsis.
Specific Indications and Uses.—Relaxation of mucous tissues, with unhealthy discharges; mercurial ulcerations; aphthous stomatitis; spongy gums; ulcerative sore throat, with fetid discharges; flabbiness and ulceration of tissues.
Related Species.—There are several species of Rhus, as the Rhus typhina, Staghorn or Velvet sumach; and the Rhus copallina, Mountain or Dwarf sumach, which possess similar virtues, and which must be carefully distinguished from those which possess poisonous properties. The non-poisonous species have their fruit clothed with acid crimson hairs, and their panicles are compound, dense, and terminal; the poisonous varieties have axillary panicles and smooth fruit (see also Rhus Toxicodendron and Related Species; and Coriaria, p. 607).