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
For up-to-date information about California vascular plants, visit the Jepson eFlora.



Dieter H. Wilken

Shrub, tree, generally dioecious or flowers bisexual and unisexual, ± resinous, sometimes milky, generally aromatic
Leaves simple or compound, alternate, deciduous or evergreen; stipules 0
Inflorescence: raceme or panicle; flowers generally many
Flower generally unisexual, radial; sepals 5, base generally ± fused; petals 5, generally > sepals, free; stamens 5 or 10, reduced and sterile in pistillate flowers; ovary superior, vestigial or 0 in staminate flowers, subtended by ± lobed, disk-like nectary, chamber generally 1, ovule generally 1, styles 1–3
Fruit drupe-like, glabrous, sticky, or short-hairy; pulp ± resinous, sometimes aromatic
Genera in family: 70+ genera, ± 850 species: tropical, warm temp; some ornamental (Rhus, Schinus ), some cultivated for fruit (Anacardium , cashew; Mangifera , mango)
Reference: [Brizicky 1962 J Arnold Arbor 43:359–375]
TOXIC: many genera produce contact dermatitis.



Shrub, tree, vine, generally dioecious
Leaves generally ternate or pinnately compound, ± resinous; leaflets 3–9, lateral generally opposite, thin to ± leathery, entire, toothed, or lobed
Inflorescence: raceme or panicle, axillary, ± open; flowers pedicelled
Flower: stamens 5, sterile or reduced in pistillate flowers; styles ± fused, stigmas 3
Fruit generally spheric, becoming papery or leathery, cream to brown; pulp resinous
Species in genus: 6 species: Am, eastern Asia
Etymology: (Latin: poisonous tree)
Reference: [Gillis 1971 Rhodora 73:161–237,370–443]
TOXIC: resin on leaves, stems, fruits causes severe contact dermatitis; one of the most hazardous plants in CA.


T. diversilobum (Torr. & A. Gray) Greene


Shrub (sometimes tree-like) 0.5–4 m or vine < 25 m
Stem: twigs glabrous to sparsely hairy, gray- to red-brown
Leaf: petiole 1–10 cm; leaflets generally 3(5), ± round to oblong, thin to ± leathery, becoming bright red in autumn, base truncate to rounded, tip obtuse to rounded, margin entire, wavy, or slightly lobed, upper surface glabrous, ± shiny, lower sparsely short-hairy; terminal leaflet 1–13 cm, 1–8 cm wide; lateral leaflets 1–7 cm, 1–6 cm wide
Inflorescence drooping, spreading, or erect; pedicels 2–8 mm; bractlets < 1 mm
Flower: sepals, petals generally ovate, yellow-green
Fruit 1.5–6 mm diam, spheric to slightly compressed, becoming leathery, glabrous to finely bristly, creamy white; pulp white, black-striate
Chromosomes: 2n=30
Ecology: Canyons, slopes, chaparral, oak woodland
Elevation: < 1650 m.
Bioregional distribution: California Floristic Province, sw edge Mojave Desert
Distribution outside California: to British Columbia, Baja California
Flowering time: Apr–May
Synonyms: Rhus d. Torr. & A. Gray

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bioregional map for TOXICODENDRON%20diversilobum being generated
N.B. The distribution depicted here differs from that given in The Jepson Manual (1993)
YOU CAN HELP US make sure that our distributional information is correct and current. If you know that a plant occurs in a wild, reproducing state in a Jepson bioregion NOT highlighted on the map, please contact us with that information. Please realize that we cannot incorporate range extensions without access to a voucher specimen, which should (ultimately) be deposited in an herbarium. You can send the pressed, dried collection (with complete locality information indicated) to us (e-mail us for details) or refer us to an accessioned herbarium specimen. Non-occurrence of a plant in an indicated area is difficult to document, but we will especially value your input on those types of possible errors (see automatic conversion of distribution data to maps).

Retrieve Jepson Interchange Index to Plant Names entry for Toxicodendron diversilobum
Retrieve dichotomous key for Toxicodendron
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
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