Erigeron rhizomatus Cronq.
Source: USDA Plants_111306
Family: Asteraceae
Erigeron rhizomatus image
Robert Sivinski  
Perennials, 25-45 cm; rhizomatous, fibrous-rooted, roots clustered, relatively thick (sometimes forming clumps to ca. 30 cm diam.), rhizomes or rhizomelike caudex branches creeping-ascending, slender , scale-leaved, without well-defined central axes. Stems erect, simple or 1-3-branched from near bases (secondary stems more densely leafy), sparsely strigose to strigoso-hirsutulous, sometimes sparsely minute-glandular. Leaves cauline; proximal blades narrowly oblong to oblong-oblanceolate, quickly linear, 50-100 × 1-3 mm, relatively even-sized distally, margins entire, ciliate, faces glabrous, eglandular. Heads 1 (rarely 2-3 from proximal branches). Involucres 6-7 × 13-16 mm. Phyllaries in 4-5 series, sparsely strigose, sometimes sparsely minute-glandular. Ray florets 25-45; corollas white with abaxial lilac midstripe , 6-7 mm, laminae not coiling or reflexing. Disc corollas 4.8-5.6 mm. Cypselae 3.5-4.5 mm, 5-6-nerved, faces glabrous; pappi: outer of setae, inner of 25-35 bristles. 2n = 18. Flowering May-Jul. Nearly barren detrital clay hillsides or benches, shale-derived soils (often seleniferous) of the Chinle or Baca formations, usually n- or e-facing slopes, ponderosa pine and piñon-juniper woodlands; of conservation concern; 2200-2400 m; Ariz., N.Mex.