Jepson Flora Project: Jepson Interchange    

 
link to manual TREATMENT FROM THE JEPSON MANUAL (1993) previous taxon | next taxon
Jepson Interchange (more information)
©Copyright 1993 by the Regents of the University of California

    THIS PAGE IS NO LONGER UPDATED
    AND IS MAINTAINED FOR ARCHIVAL PURPOSES ONLY
  • Up-to-date information about California vascular plants is available from the Jepson eFlora.

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]

RHAMNUS

BUCKTHORN

Shrub, small tree
Stem: branches alternate, flexible; twigs sometimes thorn-tipped
Leaves sometimes clustered on short-shoots, deciduous or evergreen, petioled; stipules deciduous; blade 1-ribbed from base, entire or not
Inflorescence: umbel or flowers solitary, axillary
Flower bisexual or unisexual, generally < 3 mm; hypanthium at base fused to, developing around ovary in fruit, above base deciduous; sepals 4 or 5; petals 0, 4, or 5; stamens 4 or 5; ovary appearing partly inferior, chambers 2–4, each 1–2-ovuled, style lobes 2–4
Fruit: drupe, 2–4-stoned
Species in genus: 125 species: temp, few tropical
Etymology: (Greek: name for plants of this genus)
Reference: [Wolf 1938 Rancho Santa Ana Bot Gard Monogr 1]
Some of value in medicine or as dyes.

Native

R. tomentella Benth.

HOARY COFFEEBERRY

Shrub < 6 m
Stem: bark gray or red; twigs velvety; terminal buds not covered with scales
Leaves evergreen; petiole 3–10 mm; blade 20–70 mm, ovate to narrowly elliptic, thick, base acute to rounded, tip acute, rounded, or with a small point, margin entire to toothed, sometimes rolled under, lower surface tomentose, veins prominent
Inflorescence 5–60-flowered; pedicels < 20 mm
Flower bisexual; hypanthium 1–2 mm; sepals 5; petals 5
Fruit 3-stoned, 10–15 mm, black
Ecology: Chaparral, woodlands
Elevation: < 2300 m.
Bioregional distribution: s Klamath Ranges, North Coast Ranges, Cascade Range Foothills, Sierra Nevada (except n High Sierra Nevada), Sacramento Valley, San Francisco Bay Area, South Coast Ranges, Southwestern California, East of Sierra Nevada, Mojave Desert
Distribution outside California: to Nevada, New Mexico, Baja California
Several subspp. distinguishable, but intermediates are common.

Native

subsp. cuspidata (Greene) Sawyer


Stem: twigs red, hairs of 2 lengths
Leaf: blade 20–60 mm, elliptic, upper surface green, tip abruptly narrowed to a point, margin dentate to dentate-serrate
Ecology: Chaparral, montane woodlands
Elevation: 600–2300 m.
Bioregional distribution: c&s Sierra Nevada, Tehachapi Mountain Area, Transverse Ranges, nw Peninsular Ranges, San Jacinto Mountains, East of Sierra Nevada, Mojave Desert
Flowering time: Apr–Jul
Synonyms: R. californica subsp. cuspidata (Greene) C. Wolf
Plants at high elevations sometimes deciduous
Horticultural information: DRN, DRY, SUN: 2, 3, 7, 14, 15, 16, 17, 18, 19, 20, 21.

previous taxon | next taxon
bioregional map for RHAMNUS%20tomentella%20subsp.%20cuspidata being generated
 


Retrieve Jepson Interchange Index to Plant Names entry for Rhamnus tomentella subsp. cuspidata
Retrieve dichotomous key for Rhamnus
Overlay Consortium of California Herbaria specimen data by county on this map
Show other taxa with the same California distribution | Read about bioregions | Get lists of plants in a bioregion
Return to the Jepson Interchange main page
Return to treatment index page
Glossary


University & Jepson Herbaria Home Page |
General Information | University Herbarium | Jepson Herbarium |
Visiting the Herbaria | On-line Resources | Research |
Education | Related Sites
Copyright © by the Regents of the University of California