Duration: Perennial

Nativity: Native

Lifeform: Forb/Herb

General: Herbaceous perennials, to 50 cm tall, stems erect, sometimes purplish, herbage glabrous, broken stems with clear latex, plants with a tuber-like root.

Leaves: Large, alternate, palmately 7-9 lobed, orbicular in outline, 15 cm broad or less, the lobes irregularly toothed, each tooth tipped with a slender bristle, blades sometimes dark purple in color, petioles 3-12 cm long, glabrous, stipules dissected into several finely-branched fringes up to 1 cm long.

Flowers: Dioecious, showy, pistillate flowers bright pink, petals 5, up to 10 mm long, sepals about as long as the petals, the margins spinulose-dentate, staminate flowers with 5 petals 8-12 mm long, sepals 4-6 mm long, with entire margins, the outer stamens shorter than the inner one, stamens 8-10, the filaments united below into a column, anthers in 2 whorls, the lower whorl of 5 and the upper one of 3-5, inflorescences borne in densely flowered cymes, the branches sometimes purplish, sparsely puberulent, the peduncles 1-6 cm long.

Fruits: Capsules obtusely 3-lobed, 10-13 mm long and wide, (as large or larger than the flowers), glabrous, with a small appendage near the hilum (carunculate). Seeds buff with brown or red spots, 7-9 mm long.

Ecology: Found on mesas and plains; 3,500-7,500 ft (1067-2286 m); flowering May-October.

Distribution: AZ, sw NM, s TX; south to n MEX.

Notes: This is a charismatic plant you won-t forget once you recognize it and is distinct from other species in the southwest. The large, palmately lobed, bristle-toothed leaves coming out of an erect stem with pink flowers really stands out. It emerges from a large storage root and is poisonous.

Ethnobotany: There is no use recorded for this species, but other species in this genus have uses. But this plant is poisonous.

Etymology: Jatropha comes from the Greek iatros for doctor and trophe for food, while macrorhiza means large root.

Synonyms: Jatropha arizonica, Jatropha macrorhiza var. septemfida

Editor: LCrumbacher 2012, FSCoburn 2015