Poison oak confirmed growing along a popular Bay Area hiking trail
iNaturalist: manzanita1997
Native Plants
Knowing exactly where poison oak grows along a trail you hike lets you spot its shiny three-leaf clusters before your ankles brush against them.
Someone out on Black Point Trail in Clayton, California snapped a photo of Pacific poison oak and logged it on iNaturalist, and other observers confirmed the identification enough to mark it 'research grade.' That confirmed sighting adds to a growing public record of exactly where this rash-causing native shrub pops up, which helps hikers, land managers, and fellow plant nerds know what to watch for on that trail.
Key Findings
Observation reached 'research-grade' status on iNaturalist, meaning the community-verified identification meets data quality standards for scientific use
Location pinpointed to Black Point Trail in Clayton, California, a specific and reusable trail-safety data point
Confirms presence of Toxicodendron diversilobum, a native California species known for causing contact dermatitis
chevron_right Technical Summary
A citizen scientist confirmed a research-grade sighting of Pacific poison oak along Black Point Trail in Clayton, California, adding a verified data point to a public map of where this itch-inducing native plant grows.
Abstract Preview
Original paper
Pacific poison oak (Toxicodendron diversilobum) observed in Black Point Trail, Clayton, CA, US
Research-grade observation of Pacific poison oak in Black Point Trail, Clayton, CA, US.
open_in_new Read full abstractAbstract copyright held by the original publisher.
Species Mentioned
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Toxicodendron diversilobum, commonly named Pacific poison oak or western poison oak, is a woody vine or shrub in the sumac family, Anacardiaceae.