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buck brush, common buckbrush, narrow-leaf buckthorn, sedge-leaf buckthorn, wedgeleaf cuneatus

cupped leaf ceanothus, desert ceanothus

Habit Shrubs, 0.5–3.5 m. Stems erect, ascending, or spreading, not rooting at nodes; branchlets grayish brown to brown, rigid or flexible, glabrate, puberulent, or tomentulose, hairs straight. Shrubs, 1–2 m. Stems erect, not rooting at nodes; branchlets brown to grayish brown, rigid, glabrate or tomentulose, glabrescent.
Leaves

usually both fascicled and not fascicled on same plant, rarely none fascicled;

petiole 1–3 mm;

blade flat to cupped, elliptic, oblanceolate, obovate, or orbiculate, 4–22(–30) × 3–12(–22) mm, base rounded, margins thick, not revolute, entire or denticulate distal to middle, teeth 0–9, apex obtuse, rounded, truncate, or retuse, abaxial surface pale green, glabrate or glabrous, adaxial surface green, glabrous.

not fascicled;

petiole 1–3 mm;

blade flat to ± cupped, elliptic, widely obovate, or suborbiculate, 10–20 × 7–18 mm, base rounded, margins thick, not revolute, usually sharply denticulate, sometimes weakly denticulate to almost entire, teeth 7–15, apex rounded to ± truncate, abaxial surface pale green to yellowish green, puberulent, hairs curly, glabrescent, adaxial surface green to yellowish green, sparsely puberulent, hairs curly, glabrescent.

Inflorescences

axillary or terminal, 0.8–2.5 cm.

axillary, 0.7–2 cm.

Flowers

sepals, petals, and nectary white to lavender or blue.

sepals and petals white to cream;

nectary yellow to green.

Capsules

4–6 mm wide, weakly lobed;

valves smooth, horns subapical, prominent, erect, intermediate ridges absent.

4–6 mm wide, usually not, sometimes weakly, lobed;

valves smooth, horns lateral, usually minute, sometimes absent, spreading, intermediate ridges absent.

2n

= 24.

Ceanothus cuneatus

Ceanothus perplexans

Phenology Flowering Jan–Apr.
Habitat Granitic or metamorphic substrates, rocky slopes, ridges, alluvial fans, chaparral, montane shrublands, pinyon and/or juniper and montane conifer woodlands.
Elevation 500–1900 m. (1600–6200 ft.)
Distribution
from FNA
CA; OR; nw Mexico
[WildflowerSearch map]
[BONAP county map]
from FNA
AZ; CA; Mexico (Baja California)
[WildflowerSearch map]
[BONAP county map]
Discussion

Varieties 4 (4 in the flora).

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

Ceanothus perplexans occurs in southwestern Arizona, on the desert slopes of the San Bernardino Mountains and Peninsular Ranges of southern California, and in Baja California. Ceanothus specimens from Guadalupe Island, Baja California, with entire or weakly denticulate leaf margins have been referred to either C. crassifolius or C. cuneatus, but in their leaf shape and indumentum they more closely resemble C. perplexans.

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

Key
1. Leaf blades of fascicled and non-fascicled leaves elliptic to widely oblanceolate, length usually 2+ times width; sepals, petals, and nectaries usually white, sometimes pale blue or pale lavender.
var. cuneatus
1. Leaf blades of fascicled and non-fascicled leaves widely oblanceolate, widely obovate, or orbiculate, length usually less than 2 times width, or of fascicled leaves elliptic to narrowly oblanceolate (in var. fascicularis); sepals, petals, and nectaries usually lavender to blue, sometimes pale blue, rarely white.
→ 2
2. Leaf blades of fascicled leaves elliptic to narrowly oblanceolate, 9–15 × 3–6 mm, length usually 2+ times width.
var. fascicularis
2. Leaf blades of fascicled leaves widely oblanceolate, widely obovate, or orbiculate, 4–15 × 3–12 mm, length less than 2 times width.
→ 3
3. Leaf blade margins usually entire, rarely 1–4-toothed, apices rounded, truncate, or retuse.
var. ramulosus
3. Leaf blade margins 5–9-toothed, apices rounded to truncate.
var. rigidus
Source FNA vol. 12, p. 99. FNA vol. 12, p. 107.
Parent taxa Rhamnaceae > Ceanothus > subg. Cerastes Rhamnaceae > Ceanothus > subg. Cerastes
Sibling taxa
C. americanus, C. arboreus, C. arcuatus, C. confusus, C. cordulatus, C. crassifolius, 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. 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
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. papillosus, C. parryi, C. parvifolius, C. pauciflorus, 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. cuneatus var. cuneatus, C. cuneatus var. fascicularis, C. cuneatus var. ramulosus, C. cuneatus var. rigidus
Synonyms Rhamnus cuneata C. greggii var. perplexans
Name authority (Hooker) Nuttall: in J. Torrey and A. Gray, Fl. N. Amer. 1: 267. (1838) Trelease: in A. Gray et al., Syn. Fl. N. Amer. 1(1,2): 417. (1897)
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