Erigeron sionis is a North American species of flowering plant in the family Asteraceae known by the common name Zion fleabane. It has been found in the southwestern United States, only in southern Utah. Some of the populations are inside Zion National Park, after which the species is named.Biota of North America Program 2014 county distribution mapZion Plant List, United States Department of the Interior, National Park Service
Erigeron sionis grows in shallow soil in open woodlands dominated by pine, juniper, Douglas fir, maple, and oak. It is a perennial, colony-forming herb up to 25 cm (10 inches) tall, spreading by means of stolons running along the surface of the ground. The inflorescence generally contains 1-4 flower heads. Each head contains 22–46 white ray florets surrounding many yellow disc florets.Flora of North America, Erigeron sionis Cronquist, 1947. Zion fleabane Nesom, Guy L. 1976. A new species of Erigeron (Asteraceae) and its relatives in southwestern Utah. Brittonia 28: 263-272 as Erigeron proselyticus
Varieties Erigeron sionis var. sionis Erigeron sionis var. trilobatus (Maguire ex Cronquist) S.L.Welsh
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