Ceanothus masonii

McMinn

Madroño 6: 171. 1942.

Common names: Mason's ceanothus
EndemicConservation concern
Treatment appears in FNA Volume 12. Treatment on page 103. Mentioned on page 97.

Shrubs, 0.6–2 m. Stems erect to ascending, not rooting at nodes; branchlets dark-brown, rigid, ± tomentulose. Leaves not fascicled; petiole 1–2 mm; blade flat, usually elliptic or oval, sometimes suborbiculate, 7–21 × 4–13 mm, base rounded to ± cuneate, margins not revolute, denticulate most of length, teeth 9–17, apex obtuse, rounded to truncate, abaxial surface pale green to grayish green, strigose on veins, glabrate, adaxial surface dark green, glabrous. Inflorescences axillary, 1–2.5 cm. Flowers: sepals, petals, and nectary deep blue to purple. Capsules 3–4 mm wide, not lobed; valves smooth, horns apical, minute, not rugose, intermediate ridges absent. 2n = 24.


Phenology: Flowering Feb–Apr.
Habitat: Soils derived from serpentine, chaparral, pine forests.
Elevation: 100–500 m.

Discussion

Ceanothus masonii occurs only at a few localities on Bolinas Ridge, Marin County. With the exception of its leaf morphology, it bears a close resemblance to C. gloriosus var. exaltatus.

Selected References

None.

Lower Taxa

None.

"thick" is not a number.

... more about "Ceanothus masonii"
pale green +  and grayish green +
glabrate +  and strigose +
perigynous +  and epigynous +
Rounded (?) +  and Truncate (?) +
Clifford L. Schmidt† +  and Dieter H. Wilken +
McMinn +
rounded +  and more or less cuneate +
Ceanothus sect. Cerastes +
3-veined +  and veined +
not gland-dotted +
0.7 cm7 mm <br />0.007 m <br /> (2.1 cm21 mm <br />0.021 m <br />) +
3[-5]-veined +  and pinnate +
spinulose +, spinose +, serrate +  and entire +
denticulate +, dentate +, crenulate +, crenate +  and serrulate +
suborbiculate;oval;elliptic;flat +
4mm;13mm +
not thorn-tipped +
not lobed +
0.3 cm3 mm <br />0.003 m <br /> (0.4 cm4 mm <br />0.004 m <br />) +
Mason's ceanothus +
100–500 m. +
Soils derived from serpentine, chaparral, pine forests. +
not rugose +
minute +
free +  and adnate +
0 cm0 mm <br />0 m <br /> (0.05 cm0.5 mm <br />5.0e-4 m <br />) +
unisexual +  and bisexual +
1 cm10 mm <br />0.01 m <br /> (2.5 cm25 mm <br />0.025 m <br />) +
deciduous +  and persistent +
denticulate +
intrastaminal +
superior +  and inferior +
not fleshy +
perigynous +  and epigynous +
adnate +  and distinct +
6 +  and 5 +
Clawed (?) +, Obovate (?) +  and Spatulate (?) +
0.1 cm1 mm <br />0.001 m <br /> (0.2 cm2 mm <br />0.002 m <br />) +
Flowering Feb–Apr. +
2-4-carpellate +
intermediate +
pink +, usually white +  and cream blue or purple +
distinct +
spreading +  and incurved +
6 +  and 5 +
keeled;lanceolate;deltate +
Endemic +  and Conservation concern +
not rooting +
erect +  and ascending +
Ceanothus masonii +
Ceanothus subg. Cerastes +
species +
paniclelike +  and racemelike +
not gland-tipped +
unarmed +  and armed +
polygamous +, dioecious +  and synoecious +