Ceanothus arboreus

Greene

Bull. Calif. Acad. Sci. 2: 144. 1886.

Common names: Island ceanothus
Synonyms: Ceanothus arboreus var. glaber Jepson
Treatment appears in FNA Volume 12. Treatment on page 88. Mentioned on page 81.

Shrubs, sometimes arborescent, evergreen, 2–7 m. Stems erect, not rooting at nodes; branchlets brown, not thorn-tipped, round or slightly angled in cross-section, flexible, tomentulose. Leaves: petiole 8–25 mm; blade not aromatic, flat to cupped, widely ovate to elliptic, 25–80 × 20–40 mm, herbaceous, not resinous, base rounded, margins serrulate, teeth (35–) 40–65, apex acute to obtuse, abaxial surface pale green, usually densely tomentulose, rarely glabrate, adaxial surface green, dull, glabrous or sparsely puberulent; 3-veined from base. Inflorescences axillary or terminal, paniclelike, conic, 5–12 cm. Flowers: sepals and petals pale blue to blue; nectary blue to dark blue. Capsules 6–8 mm wide, ± lobed; valves rugose, ± viscid, weakly crested. 2n = 24.


Phenology: Flowering Feb–May.
Habitat: Rocky slopes, ridges, chaparral, oak woodlands, closed-cone pine woodlands.
Elevation: 60–600 m.

Distribution

V12 876-distribution-map.jpg

Calif., Mexico (Baja California)

Discussion

Ceanothus arboreus is restricted to Santa Catalina, Santa Cruz, and Santa Rosa islands, California, and Guadalupe Island, Baja California. Plants with glabrate leaves on Santa Cruz and Santa Rosa Islands have been called C. arboreus var. glaber.

Selected References

None.

Lower Taxa

None.

"thin" is not a number.

... more about "Ceanothus arboreus"
glabrate +  and tomentulose +
puberulent +  and glabrous +
perigynous +  and epigynous +
Acute (?) +  and Obtuse (?) +
Clifford L. Schmidt† +  and Dieter H. Wilken +
Greene +
rounded +
3-veined +  and veined +
not resinous +
not gland-dotted +
2.5 cm25 mm <br />0.025 m <br /> (8 cm80 mm <br />0.08 m <br />) +
3[-5]-veined +  and pinnate +
spinulose +, spinose +, serrate +  and entire +
denticulate +, dentate +, crenulate +, crenate +  and serrulate +
not aromatic +
widely ovate;elliptic +
20mm;40mm +
not thorn-tipped +
angled +  and round +
0.6 cm6 mm <br />0.006 m <br /> (0.8 cm8 mm <br />0.008 m <br />) +
Island ceanothus +
Calif. +  and Mexico (Baja California) +
60–600 m. +
Rocky slopes, ridges, chaparral, oak woodlands, closed-cone pine woodlands. +
free +  and adnate +
0 cm0 mm <br />0 m <br /> (0.05 cm0.5 mm <br />5.0e-4 m <br />) +
terminal +  and axillary +
unisexual +  and bisexual +
conic +  and paniclelike +
5 cm50 mm <br />0.05 m <br /> (12 cm120 mm <br />0.12 m <br />) +
deciduous +  and persistent +
blue;dark blue +
intrastaminal +
superior +  and inferior +
not fleshy +
perigynous +  and epigynous +
adnate +  and distinct +
6 +  and 5 +
Clawed (?) +, Obovate (?) +  and Spatulate (?) +
0.8 cm8 mm <br />0.008 m <br /> (2.5 cm25 mm <br />0.025 m <br />) +
Flowering Feb–May. +
2-4-carpellate +
Bull. Calif. Acad. Sci. +
pale blue +  and blue +
distinct +
spreading +  and incurved +
6 +  and 5 +
keeled;lanceolate;deltate +
not rooting +
3-veined +  and veined +
Ceanothus arboreus var. glaber +
Ceanothus arboreus +
Ceanothus subg. Ceanothus +
species +
paniclelike +  and racemelike +
gland-tipped +
crested +
unarmed +  and armed +
polygamous +, dioecious +  and synoecious +