=Range and habitat.=—Tansy was originally introduced into this country as a garden plant from Europe, where it is native. It has now escaped from cultivation and is found as a weed along waysides and fences in many places from New England to Minnesota and southward to North Carolina and Missouri. =Description.=—This strong-scented perennial herb belongs to the aster family (Asteraceæ). The stout, erect stem is from 1½ to 3 feet high, branching near the top, somewhat reddish, and usually smooth. The general outline of the leaf is oval, and it is divided nearly to the midrib into about seven pairs of segments, which, like the terminal one, are again divided for about two-thirds of the distance to the midvein into smaller lobes having saw-toothed margins. The entire leaf is about 6 inches in length. Tansy is in flower from July to September, and the roundish but flat-topped yellow flower heads are produced in dense terminal clusters. =Parts used.=—At the time of flowering the leaves and tops are collected for medicinal purposes and are dried in the usual manner. The odor of tansy is strongly aromatic and the taste bitter. In drying, tansy loses about four-fifths of its weight. Tansy is employed in derangements of women, and has stimulant and tonic properties. It is also used for expelling worms. This drug is poisonous and has been known to produce fatal results. [Illustration: FIG. 16.—Tansy (_Tanacetum vulgare_ L.).] [Illustration: FIG. 17.—Gum plant (_Grindelia robusta_ Nutt.).] =Imports and prices.=—About 30,000 pounds of tanacetum or tansy are imported annually. The price paid per pound ranges from 3 to 6 cents. GUM PLANT. _Grindelia robusta_ Nutt. =Range.=—The gum plant (fig. 17) occurs in the States west of the Rocky Mountains. =Description.=—The entire plant is covered with a resinous substance, which gives it a gummy, varnished appearance, whence its common name, gum plant, is derived. This perennial of the aster family of plants has an erect habit of growth, and sends up a round, smooth stem about a foot and a half high, narrowly grooved and freely branching near the top, each branch terminating in a large yellow flower. The branches near the flower heads have a slightly reddish appearance. The pale-green leaves are about an inch long, of a leathery texture, rather rigid, coated with resin, and show numerous translucent dots. The leaves are oblong-spatulate (having a gradually narrowed base below the broader rounded summit) and are more or less clasping at the base, the lower ones somewhat saw-toothed. The yellow flowers are borne singly at the ends of the branches and measure about three-quarters of an inch across. The involucre (set of small leaves immediately beneath the flower) is very resinous and consists of numerous thick, overlapping scales, the tips of which are rolled forward.