Marah fabacea, commonly known as California manroot or bigroot, is a perennial vine native to California’s diverse habitats, including riparian zones, chaparral, and lower montane forests. It thrives in areas with seasonal water flow, such as streams and washes, and can be found at elevations up to 5249 feet (1600 meters). This vigorous plant has stout, climbing stems that can reach lengths of up to 20 feet (6 meters), supported by spiraling tendrils. From late winter to early spring, it produces yellowish-green to white flowers that are modest in size and not particularly showy. The fruit is large, spherical, and covered in spines, resembling a medieval mace. The plant’s extensive root system features large, starchy tubers.

California manroot is valued for its ability to stabilize soil and provide cover in restoration projects. It is not typically used in ornamental horticulture due to its aggressive growth and large, inedible fruit. In cultivation, it requires minimal care once established, tolerating drought and a variety of soil conditions, though it prefers well-drained soils. It can be grown in full sun to part shade. Gardeners should be aware that the plant can become invasive and difficult to remove due to its deep and extensive tuber system. There are no popular garden cultivars of this species. Historically, the tubers were used by Native Americans to immobilize fish, a testament to their toxic properties.CC BY-SA 4.0