This section is from the book "A Manual Of Weeds", by Ada E. Georgia. Also available from Amazon: A Manual Of Weeds.
Introduced. Biennial. Propagates by seeds.
Time of bloom: June to August.
Seed-time: August to October.
Range: British Columbia, Washington and Oregon; also in the East in Virginia and West Virginia and in Cape Breton Island; casual in New York and New Brunswick. Habitat: Meadows and pastures, roadsides, waste places.
An escape from gardens, and a very grave one, for the plant is very poisonous. In the green state, cattle usually leave it untouched to reproduce itself, but when cured in hay it becomes a danger to animals served with such fodder; also there is risk that the range of the weed may be extended by its transportation in baled hay. The plant is medicinal and about forty thousand to sixty thousand pounds of its dried leaves are annually imported from Europe at a cost of six to eight cents a pound. They should be collected in midflowering season of the second year of growth, dried with great care and be put up in close boxes, safe from moisture.
Stems stout, erect, round or slightly angled near the top, leafy and downy-hairy, two to five feet high, appearing in the second year of growth. Leaves of the first year all basal, forming a dense rosette, spreading flat on the ground; long-ovate, rather thick, finely toothed, tapering to petioles; the upper surface dull green and somewhat wrinkled, the under side softly hairy and netted with prominent veins; the later stem leaves are smaller, alternate and sessile or nearly so. Flowers in slender, terminal, one-sided racemes, sometimes a foot in length; corolla a swollen pale purple tube, nearly two inches long, drooping on a short pedicel, five-lobed, the lower lobe finely white-hairy within, the throat crimson-spotted; stamens four, in two unequal pairs, included in the corolla. Capsule two-celled, ovoid, rather large, containing many rough, brown seeds. (Fig. 267.)
Deep hoe-cutting of base-leaves from the roots; close cutting of flower-stalks before the development of any seeds.
 
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