California buckeye can grow to be 12-40 feet tall. It has thin grey bark that is often covered with lichens. The leaves are dark green, palmately compound with 5 to 7 leaflets. Each leaflet is 2.4-6.7 inches long, with finely-toothed margins. The flowers are sweet-scented, white to pale pink, borne on erect panicles 6-8 inches long. Most of the flowers in each cluster are male and, thus, incapable of producing seeds; only two or three at the tip are fertile and will produce the actual buckeyes, which ripen in the fall. The fruit is a fig-shaped husk 2-3 inches long, containing a large, round, orange-brown seed.

With bold, pink flowers, it may very well be the most striking of the prairie wildflowers.