|Figure 107.Tansy (Tanacetum vulgare)|
Habitat and range.This is a garden plant introduced from Europe and now escaped from cultivation, occurring as a weed along waysides and fences from New England to Minnesota and southward to North Carolina and Missouri
Description.Tansy is a strong-scented herb with finely divided, fernlike leaves and yellow, buttonlike flowers. It has a stout, somewhat reddish, erect stem, usually smooth, 1 1/2 to 3 feet high, and branching near the top. The entire leaf is about 6 inches long and is divided almost to the center into about seven pairs of segments or lobes which are again divided into smaller lobes having saw-toothed edges, thus giving the leaf a somewhat fernlike appearance. The roundish, flat-topped, buttonlike , yellow flower heads are produced in terminal clusters from about July to September. The plant contains a volatile oil which is poisonous.
Part used.The leaves and flowering tops, for which there is a reasonably constant demand, collected at the time of flowering. The volatile oil is distilled from the plant on a commercial scale in Michigan and Indiana.*
*Information on the extraction of volatile oils from plants is contained in the following publication: Sievers, A.F. Methods of extracting volatile oils from plant material and the production of such oils in the United States. U.S. Dept. Agr. Tech. Bul. 16, 36 p. illus. 1928.