Nettle

Nettle (Urtica), a genus of plants of the natural order Urticæe, having unisexual flowers, the male and female on the same or separate plants; the male flowers with a 4-parted perianth and four stamens; the female flowers with a 2-parted perianth and a tufted stigma; the fruit an achenium. The species are herbaceous plants, shrubs, or even trees, many of them covered with stinging Hairs (q.v.), which pierce the skin when touched, and emit an acrid juice, often causing much inflammation and pain. When a nettle is grasped in such a way as to press the hairs to the stem no stinging ensues; but the slightest inadvertent touch of some of the species produces very severe pain. The acridity which is characteristic of all nettles, more or less, is by some said to be due to bicarbonate of ammonia, or according to others free formic acid being present in the limpid juice secreted by the glandular hairs of the leaves and stems. The stinging of the native nettles of Europe is trifling in comparison with that of some East Indian species. U. crenulata is particularly notable for the severity of the pain which it produces, without either pustules or apparent inflammation. The first sensation is merely a slight tingling, but within an hour violent pain is felt, as if a red-hot iron were continually applied, and the pain extends far from the original spot, continues for about twenty-four hours and then abates, but is ready to return in its original intensity on the application of cold water, and does not cease for fully eight days. Cold water has a similar effect in increasing or renewing the pain of all kinds of nettles. Still more formidable than this species is U. urentissima, the Devil's Leaf of Timor. Of British species the most venomous, but the most rare, is the Roman Nettle (U. pilulifera); next to it is the Small Nettle (U. urens), frequent about towns and villages, and in waste and cultivated ground; whilst the least venomous is the most common and only perennial species, the Great Nettle (U. dioica), everywhere abundant, but particularly near human habitations, or their former sites, the desolation of which it may be said to proclaim. The roots of nettles, boiled with alum, afford a yellow dye; and the juice of the stalks and leaves has been used to dye woollen stuffs of a beautiful and permanent green. The young shoots of U. dioica have been much used in some parts of Scotland and other countries as greens, and their peculiar flavour is much relished by some, although, in general, the use of them is confined to the poor. They are valuable as anti-scorbutics, but are gritty to the taste from the quantity of crystals (Cystolithes) contained. Whatever it is that gives nettles their stinging power is dissipated by boiling and drying. The high value of nettles as food for swine is well known to the peasantry of many countries; the great nettle is cultivated in Sweden for fodder of domestic animals; and nettles are also highly esteemed as food for poultry, particularly for turkeys. The seeds are extremely nutritious to poultry, and are given to horses by jockeys, in order to make them lively when they are to be offered for sale. The stalks and leaves of nettles are employed in some parts of England for the manufacture of a light kind of beer, called Nettle Beer. The bast-fibre of nettles is useful for textile purposes. Yarn and cloth, both of the coarsest and finest descriptions, can be made of it. The fibre of U. dioica was used by the ancient Egyptians, and is still used in Piedmont and other countries. When wanted for fibre the plant is cut in the middle of summer, and treated like hemp. Nettle-cloth, or Grass-cloth, is a beautiful fabric made from rhea fibre (see BEHMERIA). The fibre of U. cannabina, a native of the south of Siberia, central Asia, is much used; and from that of U. whitlavi both fine lace and strong ropes can be manufactured. The fibre of U. japonica is much used in Japan, and that of U. argentea in the South Sea Islands; that of U. canadensis is used in Canada; and that of U. heterophylla, a widely-diffused Indian species, described by Roxburgh to be the most ferocious-looking plant he ever saw, is of very glossy silky appearance, and is manufactured into cloth in Assam. The seeds and herbage of U. membranacea are used in Egypt as emmenagogue and aphrodisiac; and somewhat similar properties are ascribed to U. dioica. U. tuberosa produces tubers, which are nutritious, and are eaten in India raw, boiled, or roasted. Australia produces a magnificent tree-nettle, U. gigas, abundant in some parts of New South Wales, ordinarily from 25 to 50 feet high, but sometimes 120 or 140 feet, with trunk of great thickness, and very large green leaves, which when young sting violently.—The Dead-nettle (q.v.) is quite a distinct plant; so is the Nettle-tree (q.v.).