TREATMENT FROM THE JEPSON MANUAL	previous taxon | next taxon Jepson Interchange (more information)
	©Copyright 1993 by the Regents of the University of California Print edition is available from the University of California Press

	The second edition of The Jepson Manual (2012) is available from the University of California Press
	See also the Jepson eFlora, which parallels the Second Edition

RHAMNACEAE

BUCKTHORN FAMILY

John O. Sawyer, Jr. (except Ceanothus)

Shrub, vine, tree, generally erect, often thorny
Leaves simple, generally alternate, often clustered on short-shoots, generally petioled, generally stipuled; blade often 1–3-ribbed from base
Inflorescence: cyme, panicle, or flowers solitary in axils
Flower generally bisexual, radial; hypanthium subtending, surrounding, or partly fused to ovary; sepals 4 or 5; petals 0, 4, or 5, clawed; stamens 4 or 5, alternate sepals, attached to hypanthium top, each generally fitting into a petal concavity; ovary superior or partly inferior, chambers 2–5, each 1–2-ovuled, style lobes or parts 1–3
Fruit: capsule, drupe
Genera in family: 55 genera, 900 species: especially tropical, subtropical; some cultivated (Ceanothus ; Colletia , anchor-plant; Gouania ; Phylica ; Rhamnus ; Ventilago ; Ziziphus )
Reference: [Brizicky 1965 J Arnold Arbor 45:439–463]

CEANOTHUS

CALIFORNIA-LILAC

Clifford L. Schmidt

Shrub, small tree, prostrate to erect, thorny or not
Stem: branches generally arranged as leaves
Leaves alternate or opposite, deciduous or evergreen, petioled; blade 1–3-ribbed from base, margin entire or not
Inflorescence: generally panicle-like aggregations of umbel-like, 3-flowered clusters
Flower generally < 5 mm; hypanthium surrounding fleshy disk below ovary base, in fruit thick, not splitting; sepals generally 5, lanceolate-deltate, incurved, colored like petals, persistent; petals generally 5, hooded, white to deep blue; stamens generally 5, opposite petals; ovary superior, 3-lobed, chambers 3, each 1-ovuled, style parts 3
Fruit: capsule, ± spheric, 3-valved
Seeds 3, ± 3 mm, 1 surface convex
Species in genus: 45 species: North America, especially w
Etymology: (Greek: thorny plant)
Reference: [Rensselaer & McMinn 1942 Ceanothus Santa Barbara Bot Gard 1–308]
Hybridization common (named hybrids not recognized here); hybrid forms may not key adequately.

Native

C. megacarpus Nutt.

Plant < 4 m
Stem: twigs round, gray to red-brown, ± tomentose, becoming gray
Leaves evergreen; stipules persistent, warty; petiole < 7 mm; blade elliptic to obovate, 1-ribbed from base, firm, tip generally notched to truncate, margin entire, upper surface flat, dull-green, glabrous, lower canescent between veins
Inflorescence raceme-like, < 2 cm
Flower white or pale lavender except disk; ovary dark
Fruit 8–12 mm; ridges 0
Ecology: Dry, shrubby slopes, canyons near coast
Elevation: < 750 m.
Bioregional distribution: Central Coast, Outer South Coast Ranges, Channel Islands.

Native

var. insularis (Eastw.) Munz

ISLAND CEANOTHUS

Plant erect
Leaves generally opposite, < 4 cm
Fruit: horns generally 0 or minute, on side or near tip
Ecology: UNCOMMON. Habitats of sp.
Elevation: < 600 m.
Bioregional distribution: Channel Islands
Synonyms: C. i. Eastw
Horticultural information: DRN, DRY, SUN: 7, 14, 15, 16, 17, 19, 20, 21, 22, 23, 24.