Erigeron breweri

A. Gray

Proc. Amer. Acad. Arts 6: 541. 1866.

Common names: Brewer’s fleabane
Treatment appears in FNA Volume 20. Treatment on page 316. Mentioned on page 270, 315, 317.

Perennials, 7–75 cm; taprooted (taproots usually not collected, often weakly developed), roots and caudices woody, branches rhizomelike (3–15 cm; fibrous-rooted), relatively slender, leafless, ascending. Stems usually ascending, sometimes prostrate to procumbent or decumbent (var. jacinteus) (often purple, distal branches stiff, spreading-ascending), hispid (hairs spreading-deflexed, 0.1–0.4 mm), mostly eglandular. Leaves cauline; (ascending) blades narrowly oblong-lanceolate to narrowly obovate, 10–40 × 2–5 mm, margins entire, relatively evenly spaced and sized, hispid, mostly eglandular. Heads 1 or 2–5(–10) in loosely corymbiform arrays. Involucres mostly 4–6 × 9–14 mm. Phyllaries in 3–5 series (all but outermost with stramineous margins and distal, greenish-herbaceous, narrowly rhomboid areas), strigoso- to hispido-hirsute or essentially glabrous, densely minutely glandular. Ray florets 20–62; corollas white or pink, often drying blue, 4–7 mm, laminae weakly coiling. Disc corollas 3.5–5.5 mm (throats slightly indurate, not inflated). Cypselae 2–3 mm, 2-nerved, faces sparsely strigose; pappi: outer of setae, inner of (15–)20–35(–50) bristles.


Varieties 5 (5 in the flora).

Erigeron breweri is treated as a member of E. sect. Linearifolii in G. L. Nesom (1992b), where all of the varieties are mapped in detail.

Selected References



1 Phyllaries glabrous or sparsely hairy, densely glandular > 2
1 Phyllaries strigoso- to hispido-hirsute, sometimes slightly glandular > 3
2 Plants usually 12–40 or 30–60 cm; stems ascending-erect; leaves usually 15–35 mm Erigeron breweri var. breweri
2 Plants 7–15 cm; stems prostrate to procumbent or decumbent; leaves 5–12 mm Erigeron breweri var. jacinteus
3 Plants 20–30 cm; stems often wiry and brittle; phyllaries hispido-hirsute (hairs translucent, spreading, stiff, relatively thick-based), glandular Erigeron breweri var. porphyreticus
3 Plants (30–)40–75 cm; stems not wiry or brittle; phyllaries strigoso- or hispido-hirsute (hairs ascending to ascending-appressed, white), eglandular > 4
4 Phyllaries strigoso-hirsute (hairs relatively thin-based, ascending-appressed, gradually and slightly reduced in density from outer to inner phyllaries), eglandular Erigeron breweri var. bisanctus
4 Phyllaries hispido-hirsute (hairs relatively thick-based, ascending, dense on outermost phyllaries, much less so on mid and inner), eglandular Erigeron breweri var. covillei