Annuals, 10-35(-40) cm. Leaves mostly opposite (distal often alternate); petioles (0-)4-11 mm; blades ovate to ovate-deltate or trullate, 1-3.5(-5) cm, margins serrate. Heads in open, lax, subcorymbiform or paniculiform (sometimes nearly cylindric) arrays. Peduncles (1-)3-10 mm, stipitate-glandular. Involucres 6-8 mm. Phyllaries stipitate- and sessile-glandular, apices acute. Corollas white, lobes sparsely hirsute. Pappi surpassing corollas. 2n = 22. Flowering (Aug-)Sep-Oct. Grassy openings, damp and shady, oak, oak-walnut, oak-pine, and pinyon pine-ponderosa pine woodlands; 1800-2700 m; Ariz., N.Mex.; Mexico.