Trixis californica

Trixis californica
Close-up of Trixis californica in Palm Canyon, California.
Conservation status
Secure (NatureServe)
Scientific classification
Kingdom:	Plantae
(unranked):	Angiosperms
(unranked):	Eudicots
(unranked):	Asterids
Order:	Asterales
Family:	Asteraceae
Subfamily:	Mutisioideae
Tribe:	Mutisieae
Genus:	Trixis
Species:	T. californica
Binomial name
Trixis californica Kellogg

Trixis californica , (American Threefold, and also Trixis), is a perennial shrub or subshrub of the Asteraceae family, the sunflower, aster, daisy family. It is found in the Southwestern United States: in the states of California, Arizona, New Mexico and Texas, and also in Mexico in the states of Baja California, Chihuahua, Coahuila, Durango, Nuevo León, Sinaloa, Sonora, Tamaulipas, and Zacatecas.

Trixis californica is one of 22 species of the genus Trixis that occur in North America, Central America, the West Indies, northern Argentina, Uruguay, and southern Brazil.

Description

Trixis californica is a sprawling shrub with bright yellow flowers that are aggregated in a flowerhead ("capitulum") of ca. 15 flowers. The inflorescence is terminal, usually panicle or corymb; rarely, the flowerheads are borne solitary at the tips of branches. Leaves are lance-shaped (lanceolate), dark green, 2–11 cm long, and 0.5–3 cm wide. This species occurs from sea level to 5000 feet elevation; found on rocky hillsides, in thorn scrub, and in deserts, especially in washes, and amongst other bushes or brush.

Sonoran Deserts

Though usually flowering February to October, depending on winter conditions, Trixis californica can flower nearly year-round. In the western Sonoran Deserts, it is exclusive to washes and is found growing only amongst other plants. In Southern California it is in the it is found mainly in the Creosote Bush scrub community of the Colorado Desert. In the Yuma Desert, east of the Colorado River, it is in the same scrub community which covers much of southwestern Arizona.

It ranges in nearly all Arizona counties, map-[1], except mostly absent in northeast counties.

References

• USDA, NRCS: United States Department of Agriculture Plants Profile: Trixis californica
• Anderson, C. 1972. A monograph of the Mexican and Central American species of Trixis (Compositae). Memoirs of the New York Botanical Garden 22(3): 1–68.
• C.Michael Hogan, ed. 2010. Trixis californica . Encyclopedia of Life

Images

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  Trixis californica - single plant form

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  Trixis californica - plant with blooms

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  Trixis californica - single flowerhead close-up

External links

• USDA PLANTS Profile - Trixis californica
• Jepson Manual treatment - Trixis californica
• Lady Bird Johnson Wildflower Center: Trixis californica profile
• NAZ Flora: Trixis californica Photos-synopsis
• Trixis californica - U.C. Photo Gallery