<html><head></head><body><div class="yahoo-style-wrap" style="font-family:courier new, courier, monaco, monospace, sans-serif;font-size:16px;"><div dir="ltr" data-setdir="false">I have been around poison ivy all my life and had at least one case of dermatitis from it every year. So I instinctively know what it looks like dormant, as a vine and most other forms. However, in the last week it hit home that there appears to be at least 2 different leaf shapes - a toothed/serrate leaf growing on the ground and a smooth margin when growing on trees. Am I correct?</div><div dir="ltr" data-setdir="false"><br></div><div dir="ltr" data-setdir="false">Do we have poison oak growing in the mid-Atlantic? This question is what made me question the various forms of poison ivy. I know that according to theory the closer to an area that an organism evolves in the more diversity in form. In languages the original home of a language can be found by the diversity of words for a concept.</div><div dir="ltr" data-setdir="false"><br></div><div dir="ltr" data-setdir="false">One interesting experience I have had with poison ivy is that when cutting thick vines on a tree with an axe the axe rang like a bell.</div><div dir="ltr" data-setdir="false"><br></div><div dir="ltr" data-setdir="false">I use jewelweed (Impatiens capensis) fresh or preserved in isopropanol to reduce contact dermatitis. If I know that I have the urushiol oil on me I try to find a flowing stream and wash it off. When I get home or to a faucet I wash (hose off) exposed skin thoroughly. All clothing that has been in contact with it is turned inside out and washed several times. I dust my shoes with baby powder or any easily available fine powder such as white flour to absorb the urushiol.</div><div dir="ltr" data-setdir="false"><br></div><div dir="ltr" data-setdir="false"> Richard Gardner</div></div></body></html>