Alkali Sunflower

Helianthus laciniatus reaches the northern extent of its range in New Mexico and Texas; it is relatively common in the Chihuahuan Desert areas of Mexico. It is similar to H. ciliaris; it usually has hairy stems as well as denser leaf indument that includes a greater number of subsessile, glandular hairs.

Perennials, 50–120(–200) cm. Stems erect, usually strigose or hispid to glabrate. Leaves cauline; opposite or alternate; sessile; blades (green or grayish, 1- or 3-nerved) lanceolate, 5–9 × 0.5–3.5 cm, bases ± cuneate, margins entire or irregularly toothed to lobed, faces strigose to strumose, gland-dotted (adaxial sometimes glaucous). Heads 1–9. Peduncles 4–13 cm. Involucres hemispheric, 10–24 mm diam. Phyllaries 16–21, lanceolate, 6–7.5 × 1.8–2.5 mm (often subequal), (margins ciliate) apices acute, abaxial faces hispidulous or strigose to glabrate, gland-dotted. Paleae 7–7.8 mm, entire or 3-toothed (apices obtuse to acute, hispid-ciliate to glabrate). Ray florets 14–20; laminae ca. 8–11 mm. Disc florets 40+; corollas 4.8–5.8 mm, lobes reddish; anthers purplish, appendages reddish (style branches yellow). Cypselae 2.7–3.5 mm, glabrate; pappi of 2(–3) aristate scales 1.4–2.5 mm. 2n = 34.

Helianthus crenatus R. C. Jackson; H. heiseri R. C. Jackson

Helianthus laciniatus is a North American species of sunflower known by the common name alkali sunflower. It is found in the southwestern United States (southeastern Arizona, southern New Mexico, western Texas) and north-central Mexico (Chihuahua, Coahuila, Nuevo León, Durango). It is fairly common in the Chihuahuan Desert.

Helianthus laciniatus is a perennial herb up to 200 cm (almost 7 feet) tall. Most of the leaves are on the stem rather than clumped together close to the ground, each leaf is up to 9 cm (2.7 inches) long. One plant usually produces 1-9 flower heads. Each head has with 14–20 yellow ray florets surrounding 40 or more red or purple disc florets. The plant grows in dry, alkaline desert soils.

Helianthus laciniatus là một loài thực vật có hoa trong họ Cúc. Loài này được A.Gray mô tả khoa học đầu tiên năm 1849.