WILDFLOWERS OF NEW MEXICO

The bushy, 1 1/2–3-foot tall stems grow all summer then burst into bloom with monsoon rains. Note the soft, woolly hairs that cover both the plant stem and the pinnately compound leaves with 5–6 pairs of leaflets.

FLOWER: August–November. Showy 1-inch wide (25 mm), yellow flowers have 5 crinkly, oval petals and bloom in a loose, spike-like cluster at the end of a 3–6-inch long (7.6–15 cm) stem; anthers reddish. Fruit is a slender, flat pod 1 1/2–2 3/8-inches long (3.8–6 cm), 1/4–3/8-inch wide (6–10 mm), slightly and hairy.

LEAVES: Alternate. Leaves 2 3/8–4-inch long (6–10 cm) with 5–6 pairs of oblong leaflets, each 1–2-inches long (2.5–5 cm) by 3/8–3/4-inch wide (10–20 mm), along the central rib; surfaces covered with soft hairs. Note the gland on the stem between the paired leaflets.

HABITAT: Dry, rocky, sandy soils, roadsides, disturbed areas; desert grasslands and scrub, prairies.

ELEVATION: 4,000–5,500 feet.

RANGE: AZ, NM, TX.

SIMILAR SPECIES: 6 Senna in NM, 4 with pinnate leaves, but 3 have very limited ranges. The soft hairs and number of leaflets distinguish this species. Twin-leaf Senna, S. bauhinioides, in so. NM, has twin oval leaflets. Two-leaf Senna, S. roemeriana, in the eastern half of NM, has twin lance-shaped leaflets.

NM COUNTIES: Southern NM in low-elevation, arid habitats: Dona Ana, Eddy, Grant, Guadalupe, Hidalgo, Lincoln, Luna, Otero, Socorro.