Vascular Plants - Anacardiaceae - Toxicodendron:
Toxicodendron diversilobum
Page Author: David Giblin
Pacific poison-oak 
Blooms: April-July
Habit: shrub,vine
Duration: perennial
Origin: Native
Conservation Status: Abundant; of no concern.

Distribution: Mainly west of the Cascades in Washington; British Columbia south to California, east to Nevada.
Habitat: Open woods at low elevations.
Species Description:

General: Glabrous to pubescent shrubs or climbing vines 1-15 m. tall.
Leaves: Leaves trifoliate; leaflets ovate to obovate, sinuate to deeply lobed, rounded to acute, 3-7 cm. long.
Flowers: Inflorescence of loose, axillary panicles; flowers mostly imperfect, dioecious, 1-2 mm. long; calyx 5-parted, pubescent to glabrous, about half the length of the petals; petals 5, spreading; staminate flowers with 5 exerted stamens, the filaments attached to the rim of a fleshy, flat disk; ovary superior, style 1, stigmas 3.
Fruits: Fruit drupe-like, globose, glabrous, about 5 mm. long.
Accepted Name:
Toxicodendron diversilobum (Torr. & Gray) Greene
Synonyms:
Rhus diversiloba Torr. & Gray
Toxicodendron radicans (L.) Kuntze ssp. diversilobum (Torr. & Gray) Thorne

Treated in Flora of the PNW as:
Rhus diversiloba
Additional Resources:

PNW Herbaria Specimens: View list of all Toxicodendron diversilobum specimens in the Consortium of Pacific Northwest Herbaria database.

WTU Herbarium Specimens: View list of Toxicodendron diversilobum specimens in the WTU Herbarium database.

Washington Flora Checklist: Toxicodendron diversilobum treatment.

E-Flora BC: Toxicodendron diversilobum atlas page.

CalPhotos: Toxicodendron diversilobum images.

USDA Plants Database: Toxicodendron diversilobum.
Additional photographs of Toxicodendron diversilobum:
(click on a thumbnail to view larger photo)

Ben Legler, 2004

Ben Legler, 2004

Ben Legler, 2004

Ben Legler, 2004

Ben Legler, 2005

Ben Legler, 2005

Ben Legler, 2005

Ben Legler, 2005

Ben Legler, 2005

Ben Legler, 2005

Ben Legler, 2005

G. D. Carr, 2008

G. D. Carr, 2008

G. D. Carr, 2008

G. D. Carr, 2006

G. D. Carr, 2006

G. D. Carr, 2006

G. D. Carr, 2002

M. A. Carr, 2004

M. A. Carr, 2004

Rod Gilbert , 2003

Rod Gilbert

Rod Gilbert

Rod Gilbert , 2005

G. D. Carr, 2010

Regina Johnson, 2011

Regina Johnson, 2011

Regina Johnson, 2011

Regina Johnson, 2012

Regina Johnson, 2012

Regina Johnson, 2014

Fred Weinmann, 2013
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Washington Native Plant Society
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