Erigeron vagus var. madsenii S.L.Welsh & N.D.Atwood
Family: Asteraceae
Erigeron vagus var. madsenii image

Non-technical Description: Madsen’s daisy is a matted, perennial forb from an intricately divided rootstalk of elongate, rhizome-like branches.  The grayish-green leaves form a basal tuft and have hairy to glandular blades 5-25 mm long x 1-3 mm wide and are tipped by three shallow, rounded teeth or lobes.  Flower heads are borne singly on a nearly leafless stalk up to 5 cm tall.  Involucres are 8-16 mm wide and 5-7 mm high and enclose 25-45 white to pinkish ray flowers.  Individual involucre bracts are often green with purplish tips or centers.  Fruits are sparsely hairy achenes topped by a pappus of bristles. Flowering occurs from May-July and again in August-September. (Fertig & Reynolds 2009; Welsh et al. 2008).

Similar Species: Payson’s daisy (Erigeron vagus var. vagus) has bright green leaves with blades 3-10 mm wide and purple or purple-tipped involucre bracts.  Cut-leaved daisy (E. compositus) has ternately compound leaves.  Cedar Breaks daisy (E. sionis var. trilobatus) is a short-lived, taprooted perennial with mostly toothed or entire leaves (rarely lobed at the tip), and flower heads 3-4.5 mm high (Welsh et al. 2008).

Habitat: Rangewide, Madsen’s daisy is found on rocky talus slopes in open Ponderosa or Bristlecone pine forests and cushion plant communities associated with the Claron Formation.  In Cedar Breaks, this species is restricted to sparsely vegetated, often chalky barrens of white Claron limestone on ridgetops and steep upper slopes.  It is typically found in cushion plant communities of Eriogonum panguicense, Hymenopappus filifolius, and Elymus lanceolatus at the edge of open woods of stunted Pinus longaeva in areas with 70% or more cover of rock and 5-10% vegetative cover.  Elevation Range:2759-3037 m (9502-9964 ft)(Fertig & Reynolds 2009).

References:  Fertig, W. and D. N. Reynolds. 2009. Survey of rare plants of Cedar Breaks National Monument: Final Report. Welsh, S.L., N.D. Atwood, S. Goodrich, and L.C. Higgins.  2008.  A Utah Flora, 2004-2008 summary monograph, fourth edition, revised.  Brigham Young University, Provo, UT.  1019 pp.

Author: Walter Fertig, Moenave Botanical Consulting, Kanab, UT. April 2017