Perennial aromatic herb from a rhizome; stems erect, simple with white matted hairs, 0.3-1.0 m tall.
Stem leaves numerous with dense, white, matted hairs on both sides or loosely woolly to green and glabrate above, lanceolate to oblanceolate or elliptic, entire to deeply lobed, the lobes sometimes again toothed or irregularly lobed, 3-9 cm long, 10-21 mm wide.
Heads disciform, numerous in a branched or narrow, spikelike inflorescence; involucres egg-shaped to bell-shaped, 2.5-4.5 mm tall; involucral bracts broadly lanceolate to egg-shaped with dense, white, matted hairs or sometimes glabrate; receptacles glabrous; female flowers 5-12; disk flowers 6-21.
This extremely variable species is represented in BC by three varieties. These may be separated as follows:
1. Principal leaves mostly entire, sometimes with a few lobes................... var. ludoviciana
1. Principal leaves more or less deeply parted or divided.
2. Leaves merely lobed, seldom subpinnately cut............. var. latiloba Nutt.
2. Leaves bipinnately cut with the ultimate segments again divided.................. var. incompta (Nutt.) Cronq.