2. LYONOTHAMNUS A. Gray.
A tree or shrub, with scaly bark exfoliating in long strips, stout terrete pubescent ultimately glabrous branchlets, and scaly, acuminate buds. Leaves opposite, long-petiolate, lanceolate, acuminate, rounded or cuneate at base, entire, finely crenulate-serrate or serrulate lobulate below the middle, or sometimes irregularly pinnately parted into 3—8 linear-lanceolate remote lobulate segments, coriaceous, transversely many-veined, dark green above, paler and more or less pubescent below, persistent; stipules lanceolate, acute, minute, caducous. Flowers on slender pedicels, in broad compound terminal pubescent cymose corymbs, with minute acute persistent bracts and bractlets; calyx-tube hemispheric, with 1—3 bractlets, tomentose on the outer surface, the lobes nearly triangular, slightly keeled, apiculate, persistent; disk 10-lobed, with a slightly thickened margin; petals 5, orbicular, sessile, white; stamens 15, inserted in pairs opposite the petals and singly opposite the sepals; filaments subulate, incurved, as long as the petals; anthers oblong, 2-celled, the cells opening longitudinally; carpels 2, inserted in the bottom of the calyx-tube, forming a superior glandular, hairy ovary; styles 2, spreading; stigmas capitate, truncate; ovules 4 in each cell, suspended; micropyle superior; raphe ventral. Fruit of 2 woody ovoid glandular-setulose carpels, dehiscent on the ventral and partly dehiscent on the dorsal suture. Seeds ovate-oblong, pointed at the ends; seed-coat light brown, thin and membranaceous; hilum orbicular, apical; raphe broad and wing-like; cotyledons oblong, acuminate, twice as long as the straight radicle directed toward the hilum.
Lyonothamnus is represented by a single species found only on the islands off the coast of southern California.
Lyonothamnus, in honor of its discoverer, William S. Lyon.
1. [Lyonothamnus floribundus] A. Gray. Ironwood.
Leaves 4′—8′ long, ½′ wide when entire, or 4′ wide when pinnately divided, when they unfold covered below with hoary deciduous tomentum, at maturity dark green and lustrous above and yellow-green, glabrous or pubescent below, with an orange-colored midrib. Flowers in June and July, ⅛′—¼′ in diameter, in clusters varying from 4′—8′ across. Fruit ripens in August and September, 3/16′ long.
A bushy tree, rarely 30°—40° high, with a single straight trunk 8′—10′ in diameter, and slender branchlets at first pale orange color and coated with deciduous pubescence, becoming at the end of their first season bright red and lustrous; usually shrubby, with several tall stems, or in exposed situations a low bush. Bark ⅓′ thick, dark red-brown, and composed of numerous thin papery layers, forming after exfoliating long loose strips persistent on the stem. Wood heavy, hard, close-grained, bright clear red faintly tinged with orange.
Distribution. Steep slopes of cañons in dry rocky soil; on the islands of Santa Catalina, Santa Cruz, San Clemente, Santa Rosa, California; most abundant and of its largest size on the northern shores of Santa Cruz; on Santa Catalina much smaller and rarely arborescent.
Now occasionally cultivated in California.