Helianthus eggertii Small

Helianthus eggertii is similar to H. strumosus and H. laevigatus; it is distinguished by the distinctive blue coloration of stems and leaves and by the leaves usually 1-nerved, in contrast to the 3-nerved condition typical for the genus. It is listed federally as an endangered species; R. L. Jones (1994) found it to be more common than was previously thought, and it is now in the process of being removed from the federal list.

Perennials, 30–200+ dm (rhi-zomatous). Stems erect, glabrous (distinctively bluish, glacous). Leaves cauline; all or mostly opposite; sessile; blades (1-nerved) lanceolate to lance-ovate, 7–16.5 × 1.5–3.5 cm, bases cuneate, margins entire or serrulate, faces glabrous (abaxial) or strumose (adaxial), gland-dotted. Heads 1–5. Peduncles 1–4 cm. Involucres hemispheric, 10–25 mm diam. Phyllaries 30–38, lance-olate, 12–16 × 3.5–4.5 mm, (margins ciliate) apices acuminate, abaxial faces glabrate, not gland-dotted. Paleae 9–11 mm, entire or ± 3-toothed (apices deltate). Ray florets 10–18; laminae 15–20 mm. Disc florets 70+; corollas 5–7 mm, lobes yellow; anthers dark, appendages dark or ± yellowish. Cypselae 4–6 mm, glabrous; pappi of 2 aristate scales 3–4 mm plus 0–1 deltate scales 0.5–1 mm. 2n = 102.