''There is also a page with the title Poison Oak with a captial 'O.'

The name Poison oak refers to various species of the toxicodendron genus that grow in North America.

• Western Poison-oak (Toxicodendron diversilobum or Rhus diversiloba) is found only on the Pacific Coast of North America, ranging from southern Canada to Baja California.
• Atlantic Poison-oak (Toxicodendron pubescens or Rhus toxicarium) grows mostly in sandy soils in eastern parts of the United States.