This section is from the book "A Manual Of Weeds", by Ada E. Georgia. Also available from Amazon: A Manual Of Weeds.
Native. Perennial. Propagates by seeds.
Time of bloom: July to October.
Seed-time: September to December.
Range: Minnesota to the Saskatchewan and Idaho, southward to Texas and New Mexico. Habitat: Grasslands.
Closely grazed pastures are sometimes badly overgrown with this weed, for cattle will not eat the bitter foliage and the plant is left to reproduce itself.
Stems tufted, ten to twenty inches tall, smooth, woody at the base, the younger parts silky white with soft hair. Leaves also densely silken-hairy, grayish green, a half-inch to nearly two inches long, three- to five-parted, the segments very narrowly linear; lower leaves have slim petioles, often with a pair of entire or three-cleft divisions near the base; upper ones have fewer segments and are sessile. Heads very numerous in narrow terminal panicles; nearly hemispheric, about an eighth of an inch broad, nodding on short pedicels; involucral scales rounded oblong, silky-hairy. Only the central florets of the heads are fertile.
Only by breaking up the sod, and putting the ground under thorough cultivation for a year or two, can it be cleansed of the perennial roots and the dormant seeds of this obnoxious weed. Waste-land plants, the wind-blown seeds of which may infest the country side, should receive the attention of the whole community.