Ceanothus, 273, fig. 102. 1942.
Shrubs, 1–3.5 m. Stems erect to ascending, not rooting at nodes; branchlets grayish brown to brown, ± flexible to rigid, tomentulose. Leaves not fascicled; petiole 0–2 mm; blade flat to ± cupped, widely elliptic to obovate, 5–13 × 4–10 mm, base cuneate, margins revolute, sometimes wavy, coarsely denticulate near apex, teeth 3–5, apex truncate, retuse, or cuspidate, abaxial surface green, tomentulose, adaxial surface green, glabrous or sparsely puberulent. Inflorescences axillary or terminal, 0.6–1.8 cm. Flowers: sepals and petals white; nectary tan to brown. Capsules 4–6 mm wide, weakly lobed; valves smooth, horns minute or absent, intermediate ridges absent.
Phenology: Flowering Jan–Apr.
Habitat: Rocky slopes, chaparral.
Elevation: 500–1100 m.
Calif., Mexico (Baja California)
Ceanothus otayensis is known from the Otay and San Miguel Mountains, southern San Diego County, with at least one locality in northern Baja California. McMinn described C. otayensis as a hybrid between C. crassifolius and C. perplexans. However, neither of the putative parents occurs sympatrically with C. otayensis, and its populations do not display the increased variation expected from hybridization.
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