Juglans hindsii of the plant is as a distinct species. Some botanists and the 1993 edition of "The Jepson Manual" had classified it as "Juglans californica" subsp. "hindsii", a subspecies of "Juglans californica" (Southern California black walnut). Juglans hindsii Juglans hindsii, commonly called the Northern California walnut and Hinds' black walnut, is a species of walnut tree endemic to Northern California. It is commonly called claro walnut by the lumber industry and woodworkers, and is the subject of some confusion over its being the root stock for English walnut orchard stock. The historical range of "Juglans hindsii" is from the San Joaquin
Juglans californica "J. californica" grows in riparian woodlands, either in single species stands or mixed with California's oaks ("Quercus" spp.) and cottonwoods ("Populus fremontii"). "Juglans californica" can be either a large shrub with 1–5 trunks, or a small, single-trunked tree. The main trunk can fork close to the ground, making it look like two trees that have grown together, then diverged. It has thick bark, deeply channeled or furrowed at maturity. It has large, pinnately compound leaves with 11–19 lanceolate leaflets with toothed margins and no hair in the vein angles. It has a small hard nut in a shallowly grooved, thick