WILDFLOWERS OF NEW MEXICO

No doubt why this sprawling, bushy, densely leafy plant, reaching 18-inches tall, is called “Sundrops” when it’s covered with yellow flowers. Note the conical, tapering buds. The disk-like stigma, which extends beyond the stamens, denotes the Calylophus group, formerly a separate genus.

FLOWERS: March–November. The 2–3-inch diameter (5–7.5 cm) flowers have 4 yellow, rounded, crinkly petals, to 1 1/4 inches (30 mm) wide, and a floral tube 1/2 to 2 1/2 inches (12–63 mm) long; buds are round and conical, often with red markings, tapering to a point with tiny free sepal tips to 1/8-inch (3 mm) long. Flowers fade to pinkish-orange.

LEAVES: Alternate, linear to lance-shaped (depending on subspecies), reaching 2-inches (5 cm) long and 1/16–1/2 inch wide (1–12 mm), margins entire to toothed. The whole plant may be smooth or with spreading (not flat-lying) hairs (depending on subspecies). No small leaves clustered in the axils.

HABITAT: Sandy, gravelly, clay, gypsum, limestone soils; plains, desert grasslands and scrub, oak pinion-juniper woodlands.

ELEVATION: 3,500-7,500 feet.

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

SIMILAR SPECIES: 3 subspecies of O. hartwegii in NM. Subsp. pubescens has long, spreading hairs on stem and leaf margins; subsp. fendleri has leaves without hairs; subsp. filifolia has narrow leaves (1 mm wide), common at White Sands. Six species of yellow Oenothera (Calylophus) in NM. Toumey’s Sundrops, O. toumeyi, in the southern mountains in NM, has clusters of small leaves in the axils, and buds with free sepal tips to 1/2-inch (12 mm) long. The widespread Yellow Sundrops, O. serrulata, and Berlandier’s Sundrops, O. berlandieri, have square buds.

NM COUNTIES: Nearly statewide (absent Colfax, Mora, Taos cos.) in low- to mid-elevation arid habitats.

NOTE: The Calylophus genus, which has club-shaped stigmas, are now lumped with Oenothera species, which have cross-shaped stigma lobes.