FERULA, Pennel-giant, in botany: A genus of the digynia order, belonging to the pentandria class of plants; and in the natural method ranking under the 45th order, Umbellatae. The fruit is oval, compressed plane, with three striae on each side. There are nine species; all of them herbaceous perennials, rising from three to ten or twelve feet high, with yellow flowers. They are propagated by seeds, which should be sown in autumn; and, when planted out, ought to be four or five feet distant from each other, or from any other plants; for no other will thrive under their shade. The drug assafetida is obtained from a species of ferula; though not peculiarly, being also produced by some other plants.