WILDFLOWERS OF NEW MEXICO

This compact 2–12-inch tall and wide plant with multiple stems looks like a 3-leaf clover, but its solid yellow flowers and sharp, sour taste place it in the Oxalis family. Tiny hairs lie flat against the stem. Note the cluster of 1–5 flowers and densely hairy seed capsules. The flavorful leaves of Oxalis species can cause painful poisoning if over-eaten.

FLOWER: March–October. Hairy flower stalks extend above the leaves; 1–5 flowers are clustered in an umbel (stems radiate from a single point) with small, narrow bracts at base; flowers have 5 petals, each 1/4–1/2-inch long (5–12 mm). The fruit is a 3/8–1-inch long (8–25 mm), hairy, narrow capsule.

LEAVES: Basal and alternate on stem. Three heart-shaped leaflets crown a slender stem (petiole) up to 1 1/2-inches long (38 mm) and covered with tiny hairs. Note the inconspicuous, leaf-like stipules at the base of each leaf stem. Leaves tend to fold up in the heat.

HABITAT: Sandy, gravelly soils of grassy openings, disturbed areas; grasslands, pinyon-juniper, ponderosa forests.

ELEVATION: 4,300–9,300 feet.

RANGE: Widespread in every state except CA, NV.

SIMILAR SPECIES: Flora Neomexicana III a: Field Keys (Allred, 2012) lists 3 yellow Oxalis species in NM with O. dillenii and O. stricta lumped into O. albicans. Other authors separate the species or lump then differently. The look-alike Common Yellow Woodsorrel, O. stricta, sometimes lumped with O. dillenii, usually has a single stem from the base and lacks stipules at the base of the leaves. Creeping Ladies’ Sorrel, O. corniculata, with stems that root at the nodes and purple spotted leaves, is an escaped ornamental scattered statewide. O. pilosa occurs in the mountains of Hidalgo County. Other woodsorrels are pink to violet.

NM COUNTIES (incl. O. albicans): In the western half of the state and scattered elsewhere in NM in mid- to high-elevation habitats: Bernalillo, Catron, Cibola, Colfax, Dona Ana Eddy, Grant, Hidalgo, McKinley, Rio Arriba, Roosevelt, San Juan, San Miguel, Sierra, Socorro, Torrance, Union, Valencia.