Helianthus winteri is described from Fresno and Tulare Counties in the southern Sierra Nevada foothills of California. It is distinguished from H. annuus by its woody trunk, year-round blooming, and morphological characteristics. It occurs in open, ungrazed foothill woodlands and annual grasslands on well-drained, granitic soils, generally on lower-elevation, south-facing foothill slopes east of the San Joaquin Valley.
Stebbins, John C.; Winchell, Chris J.; and Constable, John V. H.
"Helianthus winteri (Asteraceae), a New Perennial Species From the Southern Sierra Nevada Foothills, California,"
Aliso: A Journal of Systematic and Evolutionary Botany:
1, Article 4.
Available at: http://scholarship.claremont.edu/aliso/vol31/iss1/4