Prairie Fleabane

Annuals, biennials, or short-lived perennials, 30–70 cm; fibrous-rooted, caudices simple, sometimes lignescent, sometimes producing rhizomes that bear leaf tufts at upturned ends. Stems erect or ascending, sparsely to moderately strigose to strigillose or hirsuto-strigillose (hairs usually ascending, rarely spreading, 0.1–1.2 mm), eglandular. Leaves basal (usually persistent through flowering) and cauline; basal blades spatulate to broadly or narrowly oblanceolate to linear, (10–)30–150(–170) × 5–15(–21) mm, cauline usually gradually reduced distally, continuing to near heads, margins entire or shallowly to deeply serrate or crenate, faces glabrous or glabrate to sparsely strigose or strigoso-hirsute, eglandular. Heads 10–200+ in loosely corymbiform to paniculiform-corymbiform arrays (on distal branches). Involucres (2–)3–4 × 5–12 mm. Phyllaries in 2–4 series, glabrous, strigose, or sparsely hirsute, sometimes minutely glandular. Ray florets 50–100; corollas white, less commonly pinkish or bluish, 4–6 mm, laminae coiling. Disc corollas 1.5–2.5 mm (throats sometimes slightly indurate and inflated). Cypselae (0.5–)0.9–1.2 mm, 2-nerved, faces sparsely strigose; pappi: outer crowns of setae or scales, inner 0 (rays) or of 8–15 bristles (disc).

Erigeron annuus (Linnaeus) Persoon subsp. strigosus (Muhlenberg ex Willdenow) Wagenitz

Erigeron strigosus is a species of flowering plant in the family Asteraceae known by the common names prairie fleabane, common eastern fleabane, and daisy fleabane.

Erigeron strigosus is native to eastern and central North America as far west as Manitoba, Idaho and Texas. It has also become naturalized in western North America as well as in Europe and China as a somewhat weedy naturalized species.

Erigeron strigosus is an annual or biennial herb reaching heights of up to 80 cm (32 inches). It has hairy, petioled, non-clasping, oval-shaped leaves a few centimeters long mostly on the lower part of the plant. One plant can produce as many as 200 flower heads in a spindly array of branching stems. Each head is less than a centimeter (0.4 inches) wide, containing 50–100 white, pink, or blue ray florets surrounding numerous yellow disc florets.

Varieties Erigeron strigosus var. calcicola J. R. Allison - Alabama, Georgia, Tennessee Erigeron strigosus var. dolomiticola J. R. Allison - Alabama Erigeron strigosus var. strigosus - much of North America; introduced in China Erigeron strigosus var. septentrionalis (Fernald & Wiegand) Fernald - much of North America; introduced in Europe