Lyonothamnus floribundus ssp. aspleniifolius

Lacy, evergreen foliage and cool, honey-brown peeling bark set this California native apart. A large shrub or small tree, to 15 ft, it has large, Sorbus-like, white flower clusters. Best in full sun, with little summer water. Out of the wind, cold hardy and evergreen to 10 to 15° F, USDA zone 8a; exposed to the wind, less cold hardy, to only upper USDA zone 8.

Though first discovered in 1884 by William Lyon and named in part in his honor, it is a Florentine nobleman, Dr. Franceschi, who is credited with introducing this tree into the nursery trade. This pioneering nurseryman upon finding that the seed was difficult to germinate, set out to the Channel Islands with his sons to collect a full-grown specimen with roots and all. Suspected as outlaws by the Coast Guard, they were fired upon until their vessel began to leak. Furiously bailing water, they managed to reach Santa Barbara Harbor with their prize in hand. After planting, their specimen flourished and by 1897, there was sufficient stock of Lyonothamnus floribundus ssp. asplenifolius to list it in their nursery catalogue. A slender, evergreen tree, it can reach 60' with a 20-40' spread, though it is often smaller in the garden. The attractive foliage is deep glossy green, aromatic and fernlike, and divided into deeply notched leaflets. The lower branches tend to brush the ground and the silvery-gray bark shreds off with distinctive charm in long, thin strips to reveal showy, redwood-colored inner bark. From May through June, small, white blossoms occur in large, flat clusters, 8-18" wide, creating cream-colored umbels that cover the tree. Best used in full sun with excellent drainage, it is fast growing in youth and tolerant of some aridity and drought near the coast, where it is best suited. The tree tolerates many types of soil, but requires periodic deep watering in the summer. Often multi-trunked and particularly impressive in groves, the ironwood can be used on steep, rocky slopes where few other trees will grow. When discovered in 1884, it was thought to be the rarest tree in North America. Native only to the Channel Islands, the ironwood shares its limited distribution with Quercus tomentella and Prunus lyonii. The Chumash people used the wood from this tree to make spears. Hardy to 20F. Santa Cruz, Santa Rosa, and San Clemente Islands.