1911 Encyclopædia Britannica/Asparagus

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ASPARAGUS, a genus of plants (nat. ord. Liliaceae) containing more than 100 species, and widely distributed in the temperate and warmer parts of the Old World; it was introduced from Europe into America with the early settlers. The name is derived from the Greek ἀσπάραγος or ἀσφάραγος, the origin of which is obscure. Sperage or sparage was the form in use from the 16th to 18th centuries, cf. the modern Italian sparagio. The vulgar corruption sparrow-grass or sparagrass was in accepted popular use during the 18th century, “asparagus” being considered pedantic. The plants have a short, creeping, underground stem from which spring slender, branched, aerial shoots. The leaves are reduced to minute scales bearing in their axils tufts of green, needle-like branches (the so-called cladodes), which simulate, and perform the functions of, leaves. In one section of the genus, sometimes regarded as a distinct genus Myrsiphyllum, the cladodes are flattened. The plants often climb or scramble, in which they are helped by the development of the scale-leaves into persistent spines. The flowers are small, whitish and pendulous; the fruit is a berry.

Several of the climbing species are grown in greenhouses for their delicate, often feathery branches, which are also valuable for cutting; the South African Asparagus plumosus is an especially elegant species. The so-called smilax, much used for decoration, is a species of the Myrsiphyllum section, A. medeoloides, also known as Myrsiphyllum asparagoides. The young shoots of Asparagus officinalis have from very remote times been in high repute as a culinary vegetable, owing to their delicate flavour and diuretic virtues. The plant, which is a native of the north temperate zone of the Old World, grows wild on the south coast of England; and on the waste steppes of Russia it is so abundant that it is eaten by cattle like grass. In common with the marsh-mallow and some other plants, it contains asparagine or aspartic acidamide. The roots of asparagus were formerly used as an aperient medicine, and the fruits were likewise employed as a diuretic. Under the name of Prussian asparagus, the spikes of an allied plant, Ornithogalum pyrenaicum, are used in some places. The diuretic action is extremely feeble, and neither the plant nor asparagine is now used medicinally.

Asparagus is grown extensively in private gardens as well as for market. The asparagus prefers a loose, light, deep, sandy soil; the depth should be 3 ft., the soil being well trenched, and all surplus water got away. A considerable quantity of well-rotted dung or of recent seaweed should be laid in the bottom of the trench, and another top-dressing of manure should be dug in preparatory to planting or sowing. The beds should be 3 ft. or 5 ft. wide, with intervening alleys of 2 ft., the narrower beds taking two rows of plants, the wider ones three rows. The beds should run east and west, so that the sun’s rays may strike against the side of the bed. In some cases the plants are grown in equidistant rows 3 to 4 ft. apart. Where the beds are made with plants already prepared, either one-year-old or two-year-old plants may be used, for which a trench should be cut sufficient to afford room for spreading out the roots, the crowns being all kept at about 2 in. below the surface. Planting is best done in April, after the plants have started into growth. To prevent injury to the roots, it is, however, perhaps the better plan to sow the seeds in the beds where the plants are to remain. To experience the finest flavour of asparagus, it should be eaten immediately after having been gathered; if kept longer than one day, or set into water, its finer flavour is altogether lost. If properly treated, asparagus beds will continue to bear well for many years. The asparagus grown at Argenteuil, near Paris, has acquired much notoriety for its large size and excellent quality. The French growers plant in trenches instead of raised beds. The most common method of forcing asparagus is to prepare, early in the year, a moderate hot-bed of stable litter with a bottom heat of 70°, and to cover it with a common frame. After the heat of fermentation has somewhat subsided, the surface of the bed is covered with a layer of light earth or exhausted tan-bark, and in this the roots of strong mature plants are closely placed. The crowns of the roots are then covered with 3 to 6 in. of soil. A common three-light frame may hold 500 or 600 plants, and will afford a supply for several weeks. After planting, linings are applied when necessary to keep up the heat, but care must be taken not to scorch the roots; air must be occasionally admitted. Where there are pits heated by hot water or by the tank system, they may be advantageously applied to this purpose. A succession of crops must be maintained by annually sowing or planting new beds.

The “asparagus-beetle” is the popular name for two beetles, the “common asparagus beetle” (Crioceris asparagi) and the “twelve-spotted” (C. duodecimpunctata), which feed on the asparagus plant. C. asparagi has been known in Europe since early times, and was introduced into America about 1856; the rarer C. duodecimpunctata (sometimes called the “red” to distinguish it from the “blue” species) was detected in America in 1881. For an admirable account of these pests see F. H. Chittenden, Circular 102 of the U.S. Dep. of Agriculture, Bureau of Entomology, May 1908.

The “asparagus-stone” is a form of apatite, simulating asparagus in colour.