Arctostaphylos crustacea


Leafl. W. Bot. 1: 74. 1933 ,.

Common names: Brittleleaf manzanita
Synonyms: Arctostaphylos tomentosa subsp. crustacea (Eastwood) P. V. Wells
Treatment appears in FNA Volume 8. Treatment on page 440. Mentioned on page 406, 409, 441.

Shrubs, erect, 1–3 m; burl present; twigs sparsely to densely short-hairy, sometimes glandular or long-hairy. Leaves bifacial in stomatal distribution; petiole 2–5 mm; blade dull light green abaxially, shiny dark green adaxially, oblong-ovate to oblong-lanceolate, 2–5 × 1.5–2.5 cm, base truncate to ± lobed, margins entire (sometimes toothed), sometimes cupped or ± revolute, abaxial surface smooth, glabrous or sparsely or finely tomentose, adaxial surface smooth, ± glabrous (sometimes densely tomentose). Inflorescences panicles, 2–8-branched; immature inflorescence pendent, rarely ascending, branches spreading, axis 1–2.5 cm, 1+ mm diam., sparsely to densely short-hairy, sometimes glandular, or long-hairy eglandular; bracts not appressed, proximal leaflike, distal often scalelike, from scalelike and awl-like to broadly leaflike and deltate to lanceolate, 3–8 mm, apex acute, surfaces glabrous or hairy. Pedicels 2–5 mm, glabrous or short-hairy. Flowers: corolla white, conic to urceolate; ovary white-hairy or glabrous. Fruits depressed-globose, 6–10 mm diam., glabrous or sparsely hairy. Stones distinct.


Subspecies 6 (6 in the flora).

Arctostaphylos crustacea comprises populations from central California and the Channel Islands in areas moderated by summer maritime fog. One subspecies is widespread, from the San Francisco Bay area to the Channel Islands; the others are limited in distribution.

Selected References



1 Twigs, abaxial surface of leaf blades, and immature inflorescence axes densely glandular- hairy Arctostaphylos crustacea subsp. subcordata
1 Twigs, abaxial surface of leaf blades, and immature inflorescence axes glabrous or hairy, sometimes glandular (not densely glandular-hairy) > 2
2 Twigs short-hairy and with longer hairs > 3
2 Twigs usually short-hairy (without longer hairs) > 4
3 Leaf blades ± glabrous or sparsely short-hairy abaxially. Arctostaphylos crustacea subsp. crustacea
3 Leaf blades densely short-hairy abaxially (and sometimes adaxially). Arctostaphylos crustacea subsp. crinita
4 Leaf blades tomentose abaxially. Arctostaphylos crustacea subsp. insulicola
4 Leaf blades glabrous abaxially > 5
5 Ovaries glabrous. Arctostaphylos crustacea subsp. eastwoodiana
5 Ovaries densely hairy. Arctostaphylos crustacea subsp. rosei