Juglans hindsii hindsii" x "Juglans regia"). "Paradox" rootstock is a hybrid, produced from a Northern California black walnut tree pollinated by an English walnut. The Northern California walnut is cultivated by specialty California native plant nurseries. It is used as an ornamental tree in traditional and wildlife gardens, and for habitat gardens, natural landscaping projects, and climate compatible drought tolerant gardens. The tree is also planted in habitat restoration projects. The wood of "Juglans hindsii" is commonly called claro walnut by the lumber industry and woodworkers. It is highly figured with a rich brown color and striking grain patterns, especially in the
Juglans hindsii ("Quercus" spp.) and Fremont cottonwood ("Populus fremontii") trees. "Juglans hindsii" has only one confirmed native stand remaining. It is listed as Seriously Endangered on the California Native Plant Society Rare Plant Inventory. The IUCN classification is a Vulnerable species. It is threatened by hybridization with orchard trees, urbanization, and habitat conversion to agriculture. "Juglans hindsii" is a medium-sized tree of short bulky proportions. It grows up to tall, has a single erect trunk, commonly without branches for , and a crown that can be wider than the tree is tall. Trunks commonly reach in diameter near the base of the