The first year I worked in this particular garden; I spotted what may, or may not have been poison ivy, deep in the shade of a couple of yews. Since it was small and out of the way, and I could prune the shrubs without coming in contact with it, I decided to let it be. 
Well that worked for the first year or two and then it suddenly seemed to take off. It got distinctly bigger and started sending out runners as though it was trying to convert from a small herbaceous plant into a major vine, which is apparently a thing with Poison Ivy.
You can see the one trailer running along the base of the forsythia and out towards the left into the rest of the garden.
Clearly I couldn’t keep ignoring it anymore as it was getting out to where someone (most likely me) was going to come in contact with it during the gardening season.
I went a little overboard with protection, and even though it was the middle of summer I wore long sleeves, supplemented by plastic bags over my gardening gloves, full length jeans, and rubber boots. ‘Just because you’re paranoid, doesn’t mean they aren’t out to get you.’ At any rate, I’ve seen what poison ivy can do, and I didn’t want to experience that for myself. The precautions worked, and I got the poison ivy safely cleared and into a garbage bag. I figured best not to have it go into the compost and risk exposing someone else.
Poison Ivy is very changeable which is part of the difficulty in identifying it. So I figured the more photos the better and before I removed the plant, I went on the web to confirm my identification of the plant, and found these websites really helpful: www.wikihow.com/Identify–Poison–Ivy
msue.anr.mus.edu/news/identifying_poison_ivy_isnt_always_easy_to_do
There are also a number of quizzes that are fun, if frustrating, but again they are good reminders of how changeable poison ivy is in its looks.
www.poison-ivy.org/poison-ivy-quiz
the roaming naturalist.com/2013/06/04/poison-ivy-quiz/
Close-up of the culprit for the curious.
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