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wartleaf ceanothus

wavy leaf ceanothus

Habit Shrubs, evergreen, 1–5 m. Stems erect to ascending, not rooting at nodes; branchlets green to reddish brown, not thorn-tipped, round in cross section, ± flexible to rigid, densely tomentulose. Shrubs, evergreen, 0.3–3.5 m. Stems erect, ascending, arcuate, or prostrate, not rooting at nodes; branchlets green, not thorn-tipped, round or slightly angled in cross section, flexible, villosulous.
Leaves

petiole 1–3 mm;

blade cupped to flat, linear, narrowly oblong, or oblong-elliptic, 12–50 × 6–15 mm, base obtuse to rounded, margins minutely glandular-denticulate, revolute, glands 17–31, apex obtuse, truncate, or retuse, abaxial surface pale green, densely villosulous to tomentulose, adaxial surface dark green, sparsely puberulent and glandular-papillate; pinnately veined.

petiole 1–3 mm;

blade flat or ± folded lengthwise, narrowly elliptic to oblong-elliptic or oblanceolate, 5–24 × 3–13 mm, base obtuse to rounded, margins entire or weakly glandular-denticulate most of length, ± thick, not revolute, usually wavy, sometimes not wavy, teeth 31–42, apex obtuse, abaxial surface pale green to grayish green, villosulous or glabrous and sometimes sparsely puberulent on veins, adaxial surface dark green, glabrous or sparsely puberulent; pinnately veined or faintly 3-veined from base.

Inflorescences

axillary or terminal, racemelike, 2–8 cm.

axillary, umbel-like to racemelike, 1–3.5(–7) cm.

Flowers

sepals, petals, and nectary deep blue.

sepals, petals, and nectary pale to dark blue.

Capsules

2–3 mm wide, lobed;

valves smooth, viscid when young, not or weakly crested.

3–4 mm wide, weakly lobed at apex;

valves smooth, not or weakly crested.

2n

= 24.

Ceanothus papillosus

Ceanothus foliosus

Phenology Flowering Mar–May.
Habitat Rocky ridges, slopes, and flats, chaparral, mixed evergreen forests.
Elevation 20–1500 m. (100–4900 ft.)
Distribution
from FNA
CA; Mexico (Baja California)
[WildflowerSearch map]
[BONAP county map]
from FNA
CA
[WildflowerSearch map]
[BONAP county map]
Discussion

Ceanothus papillosus occurs in the Coast Ranges from San Francisco Bay south to the Santa Ynez Mountains, Ventura County, with disjunct populations in the Santa Ana Mountains, California, and Cerro Bola, in northern Baja California. The name C. papillosus var. roweanus was originally applied to low-growing plants with ascending to spreading, arcuate branches (H. McMinn 1939). M. Van Rensselaer and McMinn (1942) later emended the circumscription to include plants with linear leaves and retuse to truncate leaf apices, but these are found throughout the range of the species. Leaves with obtuse to truncate or retuse leaf apices also can be found on the same plant. Putative hybrids with C. integerrimus and C. oliganthus have been documented (McMinn 1944). Hybrids with C. thyrsiflorus have been named C. ×regius (Jepson) McMinn. Some putatively advanced generation hybrids have narrowly elliptic, weakly papillate leaves with obtuse apices, and sometimes have been misinterpreted as belonging to C. papillosus.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Varieties 3 (3 in the flora).

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Key
1. Leaf blade abaxial surfaces moderately to densely villosulous.
var. medius
1. Leaf blade abaxial surfaces glabrous or sometimes sparsely puberulent on veins.
→ 2
2. Leaf blades ± folded lengthwise, margins wavy, glandular-denticulate.
var. foliosus
2. Leaf blades flat to ± folded lengthwise, margins not to weakly wavy, entire or weakly denticulate near apex.
var. vineatus
Source FNA vol. 12, p. 92. FNA vol. 12, p. 93.
Parent taxa Rhamnaceae > Ceanothus > subg. Ceanothus Rhamnaceae > Ceanothus > subg. Ceanothus
Sibling taxa
C. americanus, C. arboreus, C. arcuatus, C. confusus, C. cordulatus, C. crassifolius, C. cuneatus, C. cyaneus, C. dentatus, C. divergens, C. diversifolius, C. fendleri, C. ferrisiae, C. foliosus, C. fresnensis, C. gloriosus, C. griseus, C. hearstiorum, C. herbaceus, C. impressus, C. incanus, C. integerrimus, C. jepsonii, C. lemmonii, C. leucodermis, C. maritimus, C. martini, C. masonii, C. megacarpus, C. microphyllus, C. oliganthus, C. ophiochilus, C. otayensis, C. palmeri, C. parryi, C. parvifolius, C. pauciflorus, C. perplexans, C. pinetorum, C. prostratus, C. pumilus, C. purpureus, C. roderickii, C. sanguineus, C. sonomensis, C. spinosus, C. thyrsiflorus, C. tomentosus, C. velutinus, C. verrucosus
C. americanus, C. arboreus, C. arcuatus, C. confusus, C. cordulatus, C. crassifolius, C. cuneatus, C. cyaneus, C. dentatus, C. divergens, C. diversifolius, C. fendleri, C. ferrisiae, C. fresnensis, C. gloriosus, C. griseus, C. hearstiorum, C. herbaceus, C. impressus, C. incanus, C. integerrimus, C. jepsonii, C. lemmonii, C. leucodermis, C. maritimus, C. martini, C. masonii, C. megacarpus, C. microphyllus, C. oliganthus, C. ophiochilus, C. otayensis, C. palmeri, C. papillosus, C. parryi, C. parvifolius, C. pauciflorus, C. perplexans, C. pinetorum, C. prostratus, C. pumilus, C. purpureus, C. roderickii, C. sanguineus, C. sonomensis, C. spinosus, C. thyrsiflorus, C. tomentosus, C. velutinus, C. verrucosus
Subordinate taxa
C. foliosus var. foliosus, C. foliosus var. medius, C. foliosus var. vineatus
Synonyms C. papillosus subsp. roweanus, C. papillosus var. roweanus
Name authority Torrey & A. Gray: Fl. N. Amer. 1: 268. (1838) Parry: Proc. Davenport Acad. Nat. Sci. 5: 172. (1889)
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