What are the most common plants that can cause rashes when touched in North America? What are the most important ones to be aware of and avoid?
Before coming to the US I was only familiar with the nettle. I've heard about poison ivy, but I had no idea what it looked like, how common it was, or how bad a sting could be. Since then I learned to identify poison ivy and poison sumac and avoided them, but I got stung by something which was neither of the two (the severity of the sting was comparable to the nettle).
So, from a practical point of view, which stinging plants should one be aware of when hiking in North America?