(Pursh) Dunal, Mém. Mus. Hist. Nat. 5: 50. 1819.
Pursh, Fl. Amer. Sept. 2: 559. 1813;
(Rydberg) G. L. Nesom;
(Alph. Wood) A. Gray;
Biennials, perennials, or subshrubs
(perhaps flowering first year, usually short-lived), (10—)40—100 cm.
erect, usually whitish or stramineous, sometimes reddish or grayish, glabrous.
Cauline leaf blades
oval, ovate, obovate, or oblong to spatulate, oblanceolate, lanceolate, or linear, (10—)15—70 mm, lengths 2—5(—10) times widths, bases ± clasping, margins usually crenate to serrate (teeth mostly 3—6+ per cm, rounded to obtuse, resin-tipped), rarely entire, apices obtuse to acute, faces glabrous, strongly gland-dotted.
usually in open to crowded, corymbiform arrays, rarely borne singly.
broadly urceolate to hemispheric or globose, 6—11 × 8—20+ mm.
in 5—6 series, reflexed to spreading or appressed, filiform or linear to lance-linear or lance-subulate, apices usually looped to hooked, sometimes recurved to nearly straight, subterete to subulate, moderately to strongly resinous.
0 or (12—)24—36(—40); laminae 8—14 mm.
whitish, stramineous, brown, or gray, 1.5—4.5 mm, apices smooth, coronate, or knobby, faces smooth, striate, or ± furrowed;
of 2—3(—8), straight or contorted to curled, smooth or barbellulate to barbellate, subulate scales or setiform awns 2.5—5.5 mm, shorter than disc corollas.
Flowering Jul—Sep(—Oct). Disturbed sites, plains, hills, roadsides, along streams, sands, clays, and subalkaline soils; (10—)200—2900 m; Alta., B.C., Man., Ont., Que., Sask.; Ariz., Ark., Calif., Colo., Conn., Del., D.C., Idaho, Ill., Ind., Iowa, Kans., Ky., Maine, Md., Mass., Mich., Minn., Mo., Mont., Nebr., Nev., N.H., N.J., N.Mex., N.Y., N.Dak., Ohio, Okla., Oreg., Pa., R.I., S.Dak., Tex., Utah, Vt., Va., Wash., Wis., Wyo.; Mexico (Chihuahua); introduced in Asia (Ukraine).
is probably native to the Great Plains and, perhaps, Rocky Mountain areas; it is widely introduced in other areas. Some plants are intermediate between it and
, which has been treated as a variety of
). Plants of
with relatively narrow leaf blades (lengths mostly 5—8 times widths), mostly from the western part of the range of the species, have been treated as
. G. L. Nesom (1990i) and others have treated discoid plants included here in
as distinct (as
G. aphanactis, G. nuda
); Nesom reported cypselae to be dimorphic in heads of radiate plants and monomorphic in discoid plants and noted that populations with discoid plants occur mostly south and west of populations with radiate plants. According to Nesom, plants of