Sunday, July 20, 2008

Poison-ivy: “Leaves of three let it be”

All of us have itches we really shouldn’t scratch. Vaporizing the slow driver in front of me or breaking into my neighbors wine cellar and binging on Bordeaux are itches that plague me repeatedly but that I manage (so far) to avoid scratching.

A Poison-ivy (Toxicodendron radicans) rash is another thing one should avoid scratching. Obviously, the best way to ease this temptation is to avoid having it in the first place. Hence this post. Poison-ivy infests the Mesa Trail this time of year and does not always stay neatly on the side of the trail but in several locations grows between the rocks in the middle of the trail. I have seen many hikers blissfully rubbing ankles with the leaves.

Poison-ivy has and oil called urushiol on the leaves that react most unpleasantly with human skin. Contact with the oil either through touching the plant or touching something has touched the plant (e.g. your dog, your clothes) can also transfer the oil. One should note that it is not just the leaves but also the vines and roots contain this oil.

The rash caused by Poison-ivy can be a small itch or a big itch. It really depends upon your immune system. Some people get a small spot of oil on their skin and they will have a small itchy area. In others, this small exposure will cause a full body reaction. Still others seem to be immune. There are various pharmaceutical products out there to treat a Poison Ivy rash. Best to talk to your Pharmacist to determine the latest greatest. The rash can last from one to three weeks.

Poison-ivy has three green almond-shaped leaves that grow in a cluster, which is the source of the mnemonics “Leaves of three…let it be.” The leaves in our area are straight edges but I have seen pictures where the leaves are crenulated like Poison Oak (west coast), so don’t let that fool you. There is a definite sheen to the leaves that can make them shinny. In the fall the leaves can turn reddish. Note they do not make an appropriate Thanksgiving table display. The oil can remain active for years after the plant is dead so be cautious handling it.


Anonymous said...

great post

Anonymous said...

thanks for post. but don't get frustrated by slow drivers... just slow down yourself and enjoy. what's the rush?? too many fast drivers in colorado!

Anonymous said...

I am part of the Junior Ranger;s Program and we are doing trailwork at the Mesa trail. We saw a lot a poison ivy along the trails.