Carnegiea gigantea, Giant Saguaro

Southwest Desert Flora

Home to the plants of the Sonoran, Chihuahuan and Mojave Deserts

Cirsium ochrocentrum, Yellowspine Thistle

Jatropha cuneata, Physicnut

Physicnut or Limberbush has white, whitish or yellowish flowers. The flowers may be solitary as in this photo and in small clusters off of fascicles. Jatropha cuneata Physicnut or Limberbush has medium size 3-lobed fruits called capsules. The flowers and fruit bloom and set in spring through summer. Jatropha cuneata Physicnut or Limberbush has green leaves, alternate, simple and deciduous. The plants are actually without leaves for most of the year. The leaves are fascicles on short shoots and the leaf shape is obovate-spatulate. Jatropha cuneata Physicnut or Limberbush are large heavily branched shrubs with spreading branches. The stems very in color from; grayish, yellow to reddish to reddish-brown. Stems and leaves are hairless. The young shoots exude watery yellow latex and red sap in older shoots. Jatropha cuneata Physicnut or Limberbush are native to Arizona and Mexico and may grow up to 6 feet or more. Plants bloom from July to August and prefer elevations from 1,000 to 2,000 feet in elevation. Plants prefer dry mesas, rocky limestone mesas, sandy areas, slopes and bajadas. Jatropha cuneata

Scientific Name: Jatropha cuneata
Common Name: Physicnut

Also Called: Desert Limberbush, Leatherplant, Limberbush, Physicnut, Spanish (Sangre de Drago, Piñocillo, Batácora, Torote Prieto, Torote Amarillo, Matacora).

Family: Euphorbiaceae, Spurge or Euphorbia Family

Synonyms: ()

Status: Native

Duration: Perennial

Size: Up to 6.5 feet (2m)

Growth Form: Shrub; stems heavily branched, spreading, stems yellow to yellow-brown (gray), woody-succulent, glabrous, young shoots exude watery yellow latex and red in older shoots.

Leaves: Green; alternate, simple, deciduous, plants without leaves much of the year, leaves fascicles on short shoots, leaf blade obovate-spatulate, leaf margins entire, leaf surfaces glabrous, if the leaves are lobed they are usually palmate.

Flower Color: White, cream or pale yellow corolla, inflorescences on short shoots, cymes or flowers solitary; dioecious; fruiting late spring and summer, fruits are capsules.

Flowering Season: July to August

Elevation: 1,000 to 2,000 feet (0 to 600 m).

Habitat Preferences: Dry mesas, rocky limestone mesas, sandy areas, slopes and bajadas.

Recorded Range: Jatropha cuneata is rare in the United States where it is found only in Arizona and only in Pima County, mostly in Organ Pipe Cactus National Monument and in Yuma County, in the Cabeza Prieta National Wildlife Refuge. It is also found in western Mexico and throughout Baja California.

North America & US County Distribution Map for Jatropha cuneata.

U.S. Weed Information: No information available.
Invasive/Noxious Weed Information: No information available.
Wetland Indicator: No information available.
Threatened/Endangered Information: No information available.

Genus Information: The genus Jatropha consists of herbs, subshrubs, shrubs or trees. In North America there are about 14 species in the southwestern United States in AZ, NM and TX and in 1 species in Florida. Worldwide, The Plant List lists 188 accepted species names and a further 127 scientific names of infraspecific rank for the genus.

In the Southwestern United States: Arizona has 4 species of Jatropha, California, Nevada and Utah have 0 species, New Mexico has 1 species and Texas has 3 species. All data is approximate and subject to taxonomic changes.

Comments: Jatropha cuneata, or Physicnut as it is commonly called is found only in Arizona in Pima and Yuma Counties.

The type species for Arizona, (J. arizonica) is from the Santa Rita Mountains, Pima and Santa Cruz County, (Pringle).

In Southwest Desert Flora also see Ragged Nettlespurge, Jatropha macrothiza.

The genus Jatropha is a derivation of two Greek words; "iatros" for doctor or physician and trophe for food. The species epithet "cuneata" is from Latin "cuneatus, cuneata and cuneatum", meaning "pointed like a wedge" and "tapering".


The Flora of North America reports that the stems of Physicnut or Limberbush have been used in basket making. Additionally, the stems are used for basket making by the Seri people in Sonora, Mexico.

In 2007, Goldman Sachs cited Jatropha curcas as one of the best candidates for future biodiesel production.

The by-products of making biodiesel, may be used for fish or animal feed after detoxification.

According to Kearney and Peebles, 1960, a similar related species J. spathulata is said to have been in Mexico medicinally and for the manufacture of various articles from the tough, flexible stems.

Date Profile Completed: 06/27/2019
Kearney, Thomas H., Peebles, Robert H., 1960, Arizona Flora, University of California Press, Berkley and Los Angeles, California.
U.S. Dept. of Agriculture, Natural Resources Conservation Service on-line database and USGS ITIS search, (accessed 06/27/2019)
The Plant List (2013). Version 1.1. Published on the Internet; (accessed 06/27/2019).
Bijan Dehgan, FNA | Family List | FNA Vol. 12 | Euphorbiaceae | 8. Jatropha cuneata Wiggins & Rollins, Contr. Dudley Herb. 3: 272, plate 62, fig. 1. 1943. | Flora of North America North of Mexico. 16+ vols. New York and Oxford.
Seiler, John; Jensen, Edward; Niemiera, Alex; and Peterson, John, Virginia Tech; Dept of Forest Resources and Environmental Conservation; Kearney’s Sumac; on-line accessed 06/27/2019
SEINet synonyms, scientific names, geographic locations, general information, (accessed 06/22/2019).
'Jatropha', Wikipedia, The Free Encyclopedia, 10 May 2019, 18:21 UTC, [accessed 27 June 2019]