Poison ivy, Rhus radicans or Toxicodendron radicans, is an undeniable plant menace in home landscapes. I’m allergic to its plant oils, as you may be. It’s the plant we all love to hate. Purdue experts ...

Based on: Rhus Dermatitis from Rhus. Toricodendron, Radicans and Diversiloba (Poison Ivy), Its Pathology and Chemotherapy. By James B. McNair. University of Chicago Press, 1923. Price $4.00.

Figure 1. Poison ivy (Rhus radicans) is a woody shrub or vine found throughout the United States. Red-tinged leaves grow in groups of three and have smooth, fine-toothed, or lobed margins, and small, ...

- climbing plant common in eastern and central United States with ternate leaves and greenish flowers followed by white berries; yields an irritating oil that causes a rash on contact ...

- climbing plant common in eastern and central United States with ternate leaves and greenish flowers followed by white berries; yields an irritating oil that causes a rash on contact ...