53. Arctostaphylos imbricata Eastwood, Proc. Calif. Acad. Sci., ser. 4. 20: 149. 1931.
San Bruno Mountain manzanita
Arctostaphylos andersonii var. imbricata (Eastwood) J. E. Adams ex McMinn
Shrubs, prostrate or mat- or mound-forming, 0.1-1 m; burl absent; twigs densely fine-hairy with long, gland-tipped hairs. Leaves: petiole to 2 mm; blade light green, dull, orbiculate to orbiculate-ovate, 2.5-4 × 2-3 cm, base auriculate-clasping, margins entire, plane, surfaces papillate, ± scabrous, sparsely glandular-hairy. Inflorescences panicles, 3-5-branched; immature inflorescence pendent, (branches densely clustered, ± sessile), axis 0.5-1 cm, 1+ mm diam., densely fine-hairy with long, gland-tipped hairs; bracts appressed, leaflike, ovate, 5-10 mm, apex acute, surfaces glandular-hairy. Pedicels 3-5 mm, densely glandular-hairy. Flowers: corolla white, urceolate; ovary densely glandular-hairy. Fruits depressed-globose, 6-7 mm diam., glandular-hairy, (± viscid). Stones distinct. 2n = 26.
Flowering winter-early spring. Maritime chaparral on sandstone outcroppings; of conservation concern; 100-200 m; Calif.
Arctostaphylos imbricata occurs on San Bruno Mountain in San Mateo County. It is in the Center for Plant Conservation’s National Collection of Endangered Plants.