Leaves of Three, Let it Be

August 11, 2020

Photographer: Rob Sheridan 
Summary Author: Rob Sheridan 

Part of those warm summer and early fall outings across North America is an awareness of the presence of Toxicodendron radicans or poison ivy. The Toxicodendron species sap contains urushiol, an oil that helps these plants retain water but triggers a painful allergic dermatitis in susceptible individuals. Many grazing animals will eat Toxicodendron species without consequence. However, most humans suffer painful allergic contact reactions to even modest amounts of urushiol, following contact with any part of the plant. Avoidance is facilitated by quick recognition: Leaves of three, let it be! Photo taken on August 19, 2019.

Photo Details: Camera NIKON COOLPIX AW120; Software COOLPIX AW120V1.0; Exposure Time 0.0040s (1/250); Aperture ƒ/4.4; ISO equivalent 320; Focal Length (35mm) 56.