Solidago rigida subsp. humilis

Stems 40-70(-90) cm, densely (less coarsely) hispid (30-70 hairs/mm ² ). Leaves: basal (often numerous), small, rarely exceeding 120 × 50 mm; faces densely (less coarsely) hispid (20-60 hairs/mm ² ); mid to distal lanceolate to ovate. Heads in tightly clumped, usually rounded arrays, 3-13(-23.5) × (3.5-)6-13(-18) cm. Peduncles densely hispido-strigose. Phyllaries: outer densely strigillose; inner often more nearly linear, 0.7-1.2 mm wide, conspicuously strigillose. Disc corolla lobes shallow, 0.9-1.2(-1.3) mm. Cypselae usually strigillose distally. 2n = 18.

Flowering Aug-Oct. Dry to mesic, often sandy or eroded, soils, prairies and open meadows, open grassy clearings in woods; 200-1900+ m; Alta., Man., Ont., Sask.; Colo., Ill., Ind., Iowa, Kans., Mich., Mo., Mont., Nebr., N.Mex., N.Dak., Okla., S.Dak., Tex., Wis., Wyo.

Subspecies humilis is introduced in Illinois, Indiana, Michigan, and Ontario. The involucres are slightly smaller than those of typical variety.