Endemic to California, this tree was widely used by the First People -- food, tokens for games, more. Its natural habitat is five- to seven-year floodplains -- holding the soil as it steps down toward the stream, each step evidence of a deeper flood. It is now used as rootstock for the imported English Walnut (J. regia), which otherwise succumbs to an endemic soil pathogen. [And Luther Burbank developed a hybrid of the two, which he called the Paradox, also used as a rootstock.] The wood of this tree, called claro walnut, is much prized for furniture -- dark wood with an interesting grain pattern. It has been called rare and endangered -- google for more info. Check out the Winter 2020 Bay Nature article by Mary Ellen Hannibal! Herb Dengler Trail, Jasper Ridge. 6/29/2021, 10:29 am.