This section is from the book "A Manual Of Weeds", by Ada E. Georgia. Also available from Amazon: A Manual Of Weeds.
Introduced. Perennial. Propagates by seeds. Time of bloom: June to August. Seed-time: August to October.
Range: Newfoundland to Minnesota, southward to Maryland. Habitat: Moist meadows, along ditches, and in waste places.
Comfrey was brought to this country by the early settlers because of its healing virtues, and is an escape from the "Garden of Simples." The root is spindle-shaped, thick, fleshy, mucilaginous, covered with thin, black bark; it is still valued medicinally, and, when collected in late autumn, sliced lengthwise, and dried, is worth six to eight cents a pound in the drug market. (Fig. 234.)
Stems one to three feet high, branching, hairy. Lower leaves long ovate to lance-shaped, thick, rough, net-veined, hairy on both sides, narrowing at base to margined petioles; upper leaves decurrent on the stem in long, wedge-shaped wings. Flowers in curving terminal racemes, yellowish white, sometimes light purple; corolla a little more than a half-inch long, the tube somewhat dilated, the throat crested below the lobes which are very short and spreading; five stamens inserted on the tube and included; calyx with five lance-shaped segments, acute, rough, hairy. Nutlets about one-sixth of an inch long, ovoid, brown, shining, nearly smooth, the base concave and toothed.
Deep cutting, well below the crown, before the first flowers mature. Dormant seeds may furnish a young crop, but these plants are easily pulled while the taproot is small.
Fig. 234. - Comfrey (Symphytum officinale). X 1/4.
Fig. 235. -Small Bugloss (Lycopsis arven-sis). X 1/2.