Welcome to the World of Poison Ivy, Oak, and Sumac

These nasty plants cause an untold amount of misery for residents of North America. This site is here to teach you how to recognize these plants and avoid the rash that often follows exposure to them. If we are too late to prevent your rash perhaps we can help with advice on dealing with it.

There is a great deal of confusion about poison ivy vs. poison oak, and confusion is hard to avoid since there are two kinds of poison ivy and two kinds of poison oak. This site attempts to explain the four plants, where they grow, and the differences between them.

This is a totally new website as of April 28th, so there might be a few things missing, but there is much new content to explore. The free plant id is still here, but with a few conditions...

The Blog

May 21, 2015

This photo of a monster poison ivy vine was sent in by a viewer. It reminds me of the monster trees that came alive in Harry Potter.

This is very common: a nice open yard with a tree, but the tree is besieged with a massive growth of poison ivy.

May 6, 2015

Last winter I met some folks at a garden show that had invented a product to detect poison ivy, oak and sumac, by turning pink when in contact with the urushiol oil inside those plants.

April 28, 2015

We just launched this all-new version of this website at midnight on April 27, after months of working nights and weekends. We are pretty excited about the new site, as it works really well on phones and tablets, which are at least half of all site visitors.

April 12, 2015

For some reason, people seem to get particularly steamed up about poison sumac. Specifically, they yell at me when I say is it fairly rare and only grows in very wet areas.