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Toxicodendron diversilobum
Toxicodendron diversilobum (Torr. & A. Gray) Greene
Pacific Poison Oak, Western Poison Oak
Anacardiaceae (Sumac Family)
Synonym(s): Rhus diversiloba, Toxicodendron radicans ssp. diversilobum
USDA Symbol: todi
USDA Native Status: L48 (N), CAN (N)
An erect or spreading shrub or a climbing vine with 3-parted leaves and brown or whitish berries. Western Poison Oak is not a true oak, but a close relative of Poison Ivy (Toxicodendron radicans). Poison Ivy also has 3-part compound leaves, but the leaflets are not lobed and have more slender, pointed tips. Poison Ivy replaces Poison Oak east of the Pacific Coast region. Poison Oak is so widespread and common in California that it almost qualifies as the state shrub. Anyone spending time in the lowlands and foothills of the state should learn to recognize the plant and avoid it at all costs. Livestock and deer commonly browse the plant without ill effect.
From the Image Gallery
No images of this plant
Plant Characteristics
Duration: PerennialHabit: Shrub , Vine
Leaf Retention: Deciduous
Leaf Arrangement: Alternate
Leaf Complexity: Trifoliate
Leaf Shape: Obovate , Ovate
Leaf Venation: Pinnate
Leaf Margin: Lobed
Fruit Type: Drupe
Size Notes: Shrub-like, up to about 10 foot tall, or vine-like, up to about 75 feet long.
Leaf: Reddish-green early then green, brilliant red or yellow in fall.
Fruit: Grayish-white.
Bloom Information
Bloom Color: Yellow , GreenBloom Time: Mar , Apr , May
Bloom Notes: Flower inconspicuous.
Distribution
USA: CA , NV , OR , WACanada: BC
Native Distribution: Washington to Baja California, east to Arizona.
Native Habitat: Shady to open woods, streambanks, thickets in damp bottomlands.
Benefit
Warning: All parts toxic.Interesting Foliage: yes
National Wetland Indicator Status
Region: | AGCP | AK | AW | CB | EMP | GP | HI | MW | NCNE | WMVE |
Status: | FAC |
Web Reference
Webref 62 - Burke Herbarium Image Collection (2020) University of WashingtonWebref 30 - Calflora (2018) Calflora
Webref 23 - Southwest Environmental Information Network (2009) SEINet - Arizona Chapter
Additional resources
USDA: Find Toxicodendron diversilobum in USDA PlantsFNA: Find Toxicodendron diversilobum in the Flora of North America (if available)
Google: Search Google for Toxicodendron diversilobum
Metadata
Record Modified: 2023-05-25Research By: TWC Staff