I conducted a reverse Google Image search and scoured the Internet for "ouch" plants.
I got a lesson the other day in not touching a certain type of plant—-the stinging nettle!
Thankfully, upon touching it, attempting to pick off a leaf to wipe something gross of the dog we've been dog sitting, I had some hand sanitizer on me, which I promptly anointed the stinging area with. There was also a nice fresh water spigot nearby, which my hand availed itself of.
I thought it was just a standard plant in the dog park. The leaves looked innocent enough. Thank the gods and goddesses I’m not allergic!
The leaves and younger stems of this vicious herbaceous plant are fitted with stinging hairs tipped with delightful formic acid and other "fun" irritants. If touched, the needle-like hairs inject the stinging acid into the skin, triggering a burning, tingling sensation and itchy rash.
Thankfully the symptoms don't usually persist longer than twenty-four hours.
Interestingly, the cooked plant is safe to eat and is popular in some places as a vegetable or used to make nettle tea.