Eaton's aster is a perennial daisy from a creeping rhizome with minutely haired stems from 40- 100 cm in length. The leaves are smooth and hairless or rough to the touch. The leaf edges are generally entire with the lower ones being somewhat petiolate and the upper ones sessile. The long, thin leaves are linear or lanceolate in shape, and range from 5- 15 cm long and 4- 20 mm wide.
The inflorescence is leafy and long. The daisy-like flower heads have white or pink rays surrounding a yellow disk. The ray flowers number from 20- 40, with individual rays approximately 5- 12 mm in length. The involucre ranges in height from 4.5- 10 mm, with the leafy bracts thin and loose.
Eaton's aster is a wildflower of streambanks and other moist places from low elevation valleys to moderate elevations in the mountains.
Eaton's aster is found from southern British Columbia south through Washington and Oregon (east of the Cascade crest) to California, and eastward to Saskatchewan and New Mexico.
In the Columbia River gorge, it may be found between the elevations of 200'-300' east of Lyle, WA..