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 September. Seed-time: August to October. Range: Massachusetts to Ontario, Illinois, and Kansas, southward to Georgia and Louisiana. Habitat: Dry soil; grasslands, waste places.
Stem very slender, erect, one to three feet tall, hairy, with a few leaves below the middle. Basal and lower leaves two to six inches long, obovate or spatulate, narrowing to short petioles, obtuse, entire or with a few shallow teeth, rough-hairy above but covered on the under side with minute, star-shaped hairs. Heads in a narrow panicle, without leafy bracts, each about a half-inch broad, light yellow, on very slender and slightly glandular pedicels; principal bracts of the involucre in one series, nearly linear, acute, with an outer row very much shorter. Achenes spindle-shaped, with a pappus of fine, brown bristles, arranged in funnel form. (Fig. 386.)
Fig. 386. -Hairy Hawkweed (Hieracium Gronovii). X 1/4.
Two other species of Hawkweed are becoming abundant in eastern Canada and northern New York and New England. Both promptly named "King Devils" by the farmers whom they victimize. Hieracium floribundum, increasing by numerous stolons and also by flowering branches at the base; a smooth and glaucous plant except that the spatulate leaves are bristly on the margins, and sometimes on midrib and veins beneath. Heads in large dense corymbs, yellow, with blackish involucres. Hieracium florentinum, springing from a short stout rootstock, with smooth, spatulate basal leaves or sometimes sparsely bristly beneath, the scape often nearly two feet tall with manyheaded yellow corymb.
Prevent seed production and distribution by close cutting of flowering stalks while in early bloom. Cultivation of the soil destroys the perennial roots. Like the Orange Hawkweed these plants may be suppressed in grasslands by the use of salt.