The Times - Serving Waitsburg, Dayton and the Touchet Valley

The USDA's Natural Resources Conservation Service recognizes fifteen species of poison ivy, poison oak and poison sumac throughout the known world and five of those grow natively in North America.

These plants are found in wooded areas and tend to blend with more innocuous ground cover. While they aren't technically poisonous, the urushiol in them does incite allergic reactions in most who come in contact with their leaves, stems or roots.

The effects take hold from exposure to all parts of the plant, especially the sap, to someone with an allergy vary from swelling and redness to a rash that...