Now that berries are fruiting and plants are looking lush and growing happily in the sun, a lot of red flagging can be found along high traffic areas of the park. This flagging indicates nearby Poison Oak, Toxicodendron diversilobum.
Poison Oak growing in direct sun is the easiest to identify.
Its waxy, ‘puffy’ leaves stand out among the rest of the foliage.
With moderate-full shade, Poison Oak may never develop leaves.
The vines can be easily identified, though, if you know what to look for.
The branches coming off the vine typically are stubby, warty and light tan in color.
Poison Oak can also grow similarly to native blackberry, trailing along the ground.
Please be aware that if Poison Oak has never caused a reaction for you, this does not mean you are immune.
Two crews have been exposed to Poison Oak on the site and experienced varied reactions, from none at all to severe. Each time a person is exposed, their immunity to the oil (urishiol) is weakened. If you have not had a reaction after exposure, it means you haven’t been exposed to it enough for your body to produce a reaction yet. Whether or not the plant has leaves, or whether or not it is still living/growing, does not determine if the oil is present.
Washington Conservation Corps Maury Island 