glabrate

Low, corymbosely branched, glabrate; leaves pinnatifid and toothed; clasping tips of involucral scales blackish; rays none.—Waste grounds.

From The Manual of the Botany of the Northern United States Including the District East of the Mississippi and North of North Carolina and Tennessee by Asa Gray

Usually low, persistently tomentose, rarely at all glabrate; leaves much smaller, spatulate to oblong, all entire or some cut-toothed or pinnatifid; achenes glabrous.—N. Minn.,

From The Manual of the Botany of the Northern United States Including the District East of the Mississippi and North of North Carolina and Tennessee by Asa Gray

Pubescent or glabrate; stem slender, simple, with few large heads terminating slender branchlets; leaves lanceolate, very acute, narrowed to a sessile base, sparingly serrate or serrulate; scales linear-attenuate, equal, mostly herbaceous; rays blue.—N. Dak. and westward.

From The Manual of the Botany of the Northern United States Including the District East of the Mississippi and North of North Carolina and Tennessee by Asa Gray

Seeds quadrate or oblong with truncate ends, mealy-pubescent or glabrate; hilum linear.

From The Manual of the Botany of the Northern United States Including the District East of the Mississippi and North of North Carolina and Tennessee by Asa Gray

Stem scabrous-puberulent, 2–3° high; leaves linear, short, commonly twisted, roughish-puberulent or glabrate; rays very short.—Dry soil, coast of Va. and southward.

From The Manual of the Botany of the Northern United States Including the District East of the Mississippi and North of North Carolina and Tennessee by Asa Gray