Plains Fleabane

Erigeron modestus is a polyploid complex apparently incorporating genes from E. flagellaris, E. tracyi, elements of E divergens, and the Mexican E. pubescens Kunth; arbitrary identifications may be necessary. In most of its range in Texas, E. modestus is not sympatric with any of those other taxa. Forms flowering in early season (Mar–Apr) often have stems red at the bases, dentate basal leaves 30–60(–100) × 5–10(–18) mm, and single, relatively large heads (involucres 9–12 mm diam, ray florets 50–170, corollas 6.5–11 mm) on ebracteate peduncles 5–15 cm. Later season plants have nearly intricately branched stems with more numerous, much smaller, diffusely arranged heads.

Perennials (sometimes flowering early and appearing annual or biennial), 8–40 cm; usually taprooted (taproots woody or lignescent, early season forms sometimes fibrous-rooted), caudices usually woody, sometimes branched. Stems (often multiple from bases; of previous year often persistent) ascending to spreading (proximally reddish in early season, sometimes proximally woody or lignescent), loosely strigose to villous (proximal hairs sometimes spreading), often sparsely glandular. Leaves basal (often withering by late flowering) and cauline; blades oblanceolate to spatulate, 20–50(–100) × 3–7(–18) mm, gradually reduced distally, margins entire or with 1–2(–3) pairs of teeth, faces loosely strigose (hairs ascending), eglandular. Heads 1(–3+, –50 in later season, branches at first from midstem or proximally, later more distal). Involucres 3–4.5 × 6–9(–12) mm. Phyllaries in 2–3 series, sparsely to moderately hirsute, minutely glandular. Ray florets 24–65(–170); corollas white, often with abaxial midstripe, often drying lilac, 4–7(–11) mm, laminae not coiling or reflexing. Disc corollas 1.7–3.1 mm (throats indurate and slightly inflated). Cypselae 1.1–1.4 mm, 2-nerved, faces sparsely strigose; pappi: outer of setae, inner of (5–)12–17 bristles. 2n = 27, 36.

Erigeron lobatus A. Nelson var. warnockii Shinners; E. plateauensis Cronquist; E. warnockii (Shinners) Shinners

Erigeron modestus is a North American species of flowering plant in the family Asteraceae known by the common name plains fleabane. It native to northern Mexico (Coahuila, Chihuahua, Nuevo León) and the southwestern and south-central parts of the United States (Arizona, New Mexico, Texas, Oklahoma, Kansas).

Erigeron modestus is a branching perennial herb up to 40 centimeters (16 inches) tall, producing a woody taproot. The leaves are spatula-shaped and up to 10 cm (4 inches) long near the bottom of the plant but narrower and shorter farther up the stem. Flower heads sometimes can have as many as 170 white ray florets surrounding numerous yellow disc florets.