This almost hairless plant has stems 16–40-inches tall crowded with slender leaves and topped with a dense cluster of radiating, short branches that bear heads of purple, thread-like flowers. Note the narrow leaves and tall, nearly hairless stems.

FLOWER: July–August. Flower heads have 15–25 disk flowers with purple thread-like lobes (no petal-like ray flowers). The flower head is bell-shaped to cylindrical with phyllaries pressed against the flower head and with pointed tips, hairless, or with few hairs.

LEAVES: Alternate. Blades linear, lance-shaped, hairless, 2–4-inches long (5–10 cm) by 1/8–5/16-inch wide (3–8 mm) with pointed tips and entire (smooth) margins. Blades have tiny pits on bottom (use hand lens).

HABITAT: Moist sandy, gravelly soils, stream sides, ditches, roadsides; shortgrass, rolling prairies.

ELEVATION: 3,700–4,900 feet.

RANGE: AZ, CO, NM, OK, TX.

SIMILAR SPECIES: 2 species of Vernonia occur in NM. Missouri Ironweed, V. missurica, in much the same habitat and range, has hairy stems and leaves 3/4–2-inches wide (18–50 mm).

NM COUNTIES: Eastern NM plains in low-elevation, moist habitats: Chaves, Curry, De Baca, Guadalupe, Quay, Roosevelt, San Miguel, Union.