Toxicodendron vernix (L.) Kuntze
Family: Anacardiaceae
poison sumac, swamp sumac
[Rhus vernix L.]
Toxicodendron vernix image
Mary Ann Feist  
Toxicodendron vernix image
Aaron Carlson  
Toxicodendron vernix image
Mary Ann Feist  
Etymology: Toxicodendron: means "poison tree"
Plants: perennial shrub up to 20' tall, often branching from the base
Leaves: alternate, pinnately divided into 7-13 toothless, smooth leaflets
Fruits: grayish-white berry
Habitat: swamps, shade
Hazardous: Careful, this plant is hazardous!
Conservation Status: Native
Sedge meadows (including Central Poor Fens), calcareous fens, marshes, shrub carr and brushy swamps, swampy lakeshores; swamps of tamarack, tamarack-black ash, red maple-white pine, mixed conifers, tamarack-white cedar-birch, red maple-green ash, tamarack-black spruce, tamarack-white cedar-black spruce.  Almost always associated with tamarack.

The distribution of poison-sumac in Wisconsin is intriguing and probably tied to glacial history.  It is common in the Southeast Glacial Plains, especially in the Kettle Moraine region but becomes very rare and local northeast of Lake Winnebago.  It is common in rich swamps in Outagamie and Waupaca Cos. and in the numerous wetlands of the Central Sands and Central Sand Hills.  Populations in the Driftless Area are (or were) restricted to relic bogs (Hansen, 1933), many of which have been destroyed.  Increased collecting of this species has shown that it occurs farther northwest in the state than previously thought and in more counties south of the Tension Zone.

This is a beautiful species, especially in fall, with glossy leaves and ascending branches that have a tropical look.  Although many people claim to have gotten a rash from poison-sumac, it almost always grows deep in wetlands where few hikers venture.  Poison-sumac seems to prefer high-quality wetlands and appears to decline when its associate ash species succumb to emerald ash borer.  Clearly, more research is needed to understand the phytogeography and ecology of this plant.

Toxicodendron vernix image
Aaron Carlson  
Toxicodendron vernix image
Mary Ann Feist  
Toxicodendron vernix image
Aaron_Carlson  
Toxicodendron vernix image
Aaron_Carlson  
Toxicodendron vernix image
Aaron_Carlson  
Toxicodendron vernix image
Aaron_Carlson  
Toxicodendron vernix image
Aaron_Carlson  
Toxicodendron vernix image
Aaron Carlson  
Toxicodendron vernix image
Aaron Carlson  
Toxicodendron vernix image
Aaron_Carlson  
Toxicodendron vernix image
Aaron_Carlson  
Toxicodendron vernix image
Aaron_Carlson  
Toxicodendron vernix image
Mary Ann Feist  
Toxicodendron vernix image
Toxicodendron vernix image
Botanical Illustration  
Toxicodendron vernix image
Toxicodendron vernix image
Toxicodendron vernix image
Aaron Carlson  
Toxicodendron vernix image
Toxicodendron vernix image
Botanical Illustration  
Toxicodendron vernix image
Toxicodendron vernix image
Toxicodendron vernix image
Hugh H. Iltis  
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Toxicodendron vernix image
Robert W. Freckmann  
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Toxicodendron vernix image
Robert W. Freckmann  
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Toxicodendron vernix image
Robert R. Kowal  
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Toxicodendron vernix image
Robert R. Kowal  
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Toxicodendron vernix image
Paul Skawinski  
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Toxicodendron vernix image
Paul Skawinski  
Toxicodendron vernix image
Toxicodendron vernix image
Aaron Carlson  
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Kenneth J. Sytsma  
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Toxicodendron vernix image
Caroline A. Creevey  
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Toxicodendron vernix image