Arjona patagonica

Arjona patagonica is a flowering plant species in the family Schoepfiaceae, native to southern South America. It was scientifically named by Jacques Bernard Hombron and described by Joseph Decaisne in 1853 in the second volume of "Voyage au Pôle Sud et dans l'Océanie sur les corvettes l'Astrolabe et la Zélée." Although Honoré Jacquinot is credited on the title page, only Hombron is recognized as the authority for A. patagonica. In 1878, Carl Skottsberg placed A. patagonica in his section Euarjona alongside A. tuberosa.

The species is distributed across various regions of Argentina and Chile. In Argentina, it has been collected in the provinces of Buenos Aires, Chubut, La Pampa, Mendoza, Neuquén, Río Negro, San Juan, Santa Cruz, and Tierra del Fuego. In Chile, it is found in the Araucanía, Coquimbo, Libertador Bernardo O'Higgins, Magallanes, and Valparaíso regions.

Arjona patagonica has historical significance as a food source for the Ona people, who referred to it as "téen." The plant's tubers are an important dietary component for them, serving as one of their primary carbohydrate sources. The tubers measure 5 to 9mm in width and up to 20cm in length, shrinking to 2mm in diameter during flowering in spring. They are best harvested in the fall months of March and April. The tubers contain mostly water and some polyphenols. Additionally, the plant is consumed by livestock but is considered nutritionally poor in terms of palatability, digestibility, and crude protein content according to the 1987 Lara & Cruz system.