About Thelesperma megapotamicum (Spreng.) Herter
Thelesperma megapotamicum is a perennial herb or subshrub that reaches 20 to 80 cm (7.9 to 31.5 in) in height. Most of its leaves grow in opposite arrangement, and are pinnately divided into linear to filiform lobes that are 2–4 cm long and up to 2.5 mm wide. Its inflorescence holds multiple flower heads, each held in a cuplike involucre of phyllaries that have purple-tinged, pointed lobes with white edges. Each flower head contains many yellow or orange disc florets, and may sometimes have one or more yellow ray florets, though these ray florets can be absent. Its cypselae measure 5–8 mm long, and are each topped with two barbed awns around 2 mm long. This plant typically flowers from April to October. This species is native to parts of the central and southwestern United States including Arizona, Arkansas, Colorado, Kansas, Nebraska, New Mexico, Oklahoma, South Dakota, Texas, and Wyoming, northern Mexico including Chihuahua and Coahuila, and some countries in South America. It has been introduced to parts of the United States including California, Minnesota, Michigan, Illinois, and possibly Oregon. The USDA Plants database also records it as introduced to Montana and Indiana. In North America, it grows in disturbed sites on sand or clay soil, in oak or juniper woodlands, desert scrub, or yellow pine forests, at elevations ranging from 300 to 2,900 m (980 to 9,510 ft) above sea level. Native American groups including the Hopi and Navajo use this plant to make herbal teas, use it as a medicinal remedy, and produce a yellow dye from it. The Hopi name for this plant is hohoysi. The whole plant can be boiled until the water turns a rusty color to make tea. The Hopi also prepare this plant as sun tea by combining it with water in large glass jars and placing the jars in the sun. This plant is called izeets'ósé in Apache.
