Poison oak is something you do not want to take home from a hike. Being able to recognize and avoid poison oak is critical trail knowledge for all levels of hikers. It is blooming bigger and glossier than I have ever seen it on our trails before. Here is some info on this very dangerous plant, and some tips on helping you if you think you have been exposed to its oil.

Source: wikipedia

“T. diversilobum is found in California (also the original name of Los Angeles; Yangna or Iyaanga/poison oak place),[2] the Baja California peninsulaNevadaOregonWashington, and British Columbia.[3] The related T. pubescens (eastern poison oak) is native to the Southeastern United States. T. diversilobum and T. rydbergii (western poison ivy) hybridize in the Columbia River Gorge area.[4]

It thrives in shady and dappled light through full and direct sunlight conditions, at elevations below 5,000 feet (1,500 m).[4] The vining form can climb up large shrub and tree trunks into their canopies. Sometimes it kills the support plant by smothering or breaking it.

The photos below are from a recent hike up to Las Trampas Ridge…Check out the flowering Poison oak and make sure to avoid it on your next mountain outing!


Glossy leaves of 3…this is poison OAK. Do not touch. One millionth of a molecule can start the rash, especially if you are allergic like me. The rest of the photos are non toxic. 🙂