Index- plants in this Family
Anacardiaceae / Cashews
Eastern Poison Ivy (Toxicodendron radicans)
Eastern Poison Ivy is also known as Poison Ivy. Formerly considered in the genus Rhus - R. radicans.

Plant Type: This is a vine, it is a perennial. Sometimes running along the ground and slightly erect and somtimes more like a shrub it is most common form is as a vine clinging to trees with numerous small rootlets.
Leaves: The leaves are alternate. Leaves can be as wide as 20 cm (8inches). Each leaf is divided with three leaflets which are somtimes irregularly toothed. The junction of the petioles is often redish. The leaves are often shiny but somtimes dull.
Flowers: The flowers have 5 Regular Parts and are up to 0.3cm wide (0.12 inches). They are green or yellowish. Blooms first appear in late spring and continue into early summer.
Fruit: Small (about 0.5cm (0.2") green turning white, berry like in loose cluster.
Habitat: Open woods and borders.
Range: From the Rocky Mountains east.

      Color Photo     More Info      Classification

Ads on this page help pay for this site but if you see one that seems inappropriate here such as one that is counter to the pro environmental theme please let me know which Ad and I will block it.
Report a Bad Ad

This dreaded and very common vine is most often recognized by its leaves of three and the distinctive aerial rootlets. In the fall there are white berry like fruits that are eaten by birds and bright red leaves. It often climbs high on the trunk of a tree decorating it with brilliant scarlet after frost.

Warning: This plant contains the volatile oil urushiol which is highly irritating to many if not most people. The urushiol is in all parts of the plant and is very stable. People have had reactions to dry specimens over a century old.(Foster & Duke) It can be carried on smoke and inhaled which can be fatal for highly allergic people. Some people seem to be totally unaffected by it and others appear to develop a tolerance after exposure. Euell Gibbons recommended, in his book Stalking the Wild Asparagus that one eat a leaf each day as they begin to emerge in the spring starting with a tiny new leaf. This, it is supposed, will make one immune to the plant. It is an old tale and may work. Now you should be able to get commercial preparations that have the same effect and may be safer. Even if you feel you are totally unaffected by Poison Ivy you should still avoid it. Your immunity may change and you could pass the oil on to a third party via your skin or clothes. Flesh, fabric and any other type of surface that contacts the plant should be washed with soap or alcohol as soon as possible. The oil is not particularly easy to remove and, as stated above, will, if not removed, persist for a very long time. The juice of certain plants, such as Jewelweed, Impatiens capensis have a reputation for removing the oil effectively.

See the links below this image for other images. (1)
© Daniel Reed   E-mail      Image use policy

These images open in a new window. You may need to resize the window to view the entire image.
Posion Ivy - close view of flowers  © Daniel Reed

Ads on this page help pay for this site but if you see one that seems inappropriate here such as one that is counter to the pro environmental theme please let me know which Ad and I will block it. Report a Bad Ad

More Info:  
The Search below may provide more information about this species. Some of URLs may have been used as a source for this page not otherwise cited. Most of the information not cited comes from multiple sources that can be found in the Books page. The USDA plant links are provided by: USDA, NRCS 1999. The PLANTS database ( National Plant Data Center, Baton Rouge, LA 70874-4490 USA. You can check species names at ITIS Advanced Search to see if they meet the current ITIS taxonomic criteria.

By: Newcomb, Lawrence and Illustrated by Morrison, Gordon. 1977, Little, Brown and Company, ISBN:0-316-60442-9

One of the best general guides to wildflowers of the North Eastern and North Central United States. Newcomb's key is an excellent, simple method for identifying plants. Newcomb has drawings for almost every plant mentioned that are excellent aids to identifying the species. Though only the more common plants are covered this is often the first book I pick up when trying to identify a wildflower.

Wildflo wers of Tennessee the Ohio Valley and the Southern Appalachians
By: Dennis Horn and Tavia Cathcart and Thomas E. Hemmerly and David Duhl. , ISBN:1551054280

This is perhaps the best of many field guides covering this region. Featuring 446 excellent color photographs (located with the text) and mentioning as similar to those illustrated are another 800 or so species for a total coverage of over 1,200 species. The start of each family section includes line drawings of some of the species showing important features. The text includes the usual description, bloom season, range, habitat and additionally includes information such as medical uses and lore and how the species was named. This is the official field guide of the Tennessee Native Plant Society.

Angiosperms / Flowering Plants
Dicots / Two Seed Leaves



Welcome / Glossary / Books / Links / Feedback / Image use policy - Wildflowers of the Southeastern United States, Page updated on 5/7/2003 6:21:42 PM.