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Name: Jennifer
Location: N/A
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I am having difficulty in figuring of which family and genus poison ivy belongs to presently. I have always found it as Rhus radicans but have been researching it and more commonly have found it under the listing of Toxicodendron radicans (L.) Kuntz. I know that this means the nomenclature is from Linnaeus and modified by Kuntz. Has the nomenclature been revised since I learned it as being Rhus radicans and if so, when. I thought that poison ivy belongs to the family Anicardiaceae, genus Rhus, and species radicans. I am confused now and know of no sources current enough to clarify my question. If you could answer my question or refer me to a link that might be helpful, I would appreciate the help.

The generally accepted classification for poison ivy:
family: Anacardiaceae
genus: Toxicodendron
species: Toxicodendron radicans (L.) Kuntze

It is based on the first name given it by Linnaeus in 1753: Rhus radicans Linn. Sp. Pl. 266. 1753.

Kuntze moved it to the genus Toxicodendron in 1891. Toxicodendron radicans (L.) Kuntze in O. Ktze Revis. Gen. Pl. 1: 153. 1891

There are occasionally individuals who use the older name.


Anthony R. Brach

I learned in forestry school in the 60's that poison ivy had been "moved" from the genus Rhus to Toxicodendron, but when I began work as a naturalist in Illinois a decade later all the references called it Rhus again. I do not try to keep up with technical botany so can't tell you "which way the wind is blowing." The family will be the same as sumac, at any rate. I don't have any links at hand, but you might try the NRCS plant data base at, or the National Biological Survey, they have a lot of this sort of thing. It just goes to show, even though scientific nomenclature goes a long way to clearing confusion, people will always find something to argue about.

J. Elliott

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