Status: Native
Synonyms:
Rhus radicans Linnaeus var. rydbergii (Small ex Rydberg) Rehder
Rhus rydbergii Small ex Rydberg
Toxicodendron rydbergii can assume different morphology depending on its
location. It can be a vine-like Ivy, as the name suggests. The viney growth pattern occurs as it grows over rocks. More commonly in the Gila Wilderness,
it is erect and few-branched up to a few feet tall with trifoliate, shiny, dentate leaves. Large stands with this morphology occur along creeks and rivers in the area. The flowers are inconspicous and are in small axillary clusters. The fruit is a yellow drupe.
Most people have an allergic reaction to poison ivy, becoming sensitized by repeated exposure. The reaction is a contact dermatitis, with a severe form consisting of weeping open blisters. The more severe reactions require treatment by a physician, while milder ones can be treated with over the counter medications. The offending agent in the plant is the chemical Urushiol. The appearance of the rash may be delayed by a few days after exposure in some people so that it may be difficult to figure out the cause of the reaction.
Please click on an image for a larger file.
Toxicodendron rydbergii, photo Russ Kleinman, Burro Mtns., Saddlerock Cyn., June 18, 2007
Toxicodendron rydbergii, photo Russ Kleinman, Andy Anderson & Richard Felger, Little Creek, May 11, 2008
Toxicodendron rydbergii, viney growth pattern, photo Russ Kleinman, Burro Mtns., Saddlerock Canyon, Sept. 14, 2008
Toxicodendron rydbergii, winter appearance, photo Russ Kleinman, Pinos Altos Range, McMillen Campground, January 18, 2010
Toxicodendron rydbergii, closeup of drupes, broad leaf scars with five vascular bundles, and buds on winter twig, photo Russ Kleinman, Pinos Altos Range, McMillen Campground, January 18, 2010
Toxicodendron rydbergii, field macro of drupe, photo Russ Kleinman, Pinos Altos Range, McMillen Campground, January 18, 2010
Toxicodendron rydbergii, closeup of winter twig, photo Russ Kleinman, Pinos Altos Range, McMillen Campground, January 18, 2010
Toxicodendron rydbergii, field macro of buds and leaf scars on winter twig, photo Russ Kleinman, Pinos Altos Range, McMillen Campground, January 18, 2010
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