Yeppers. It sure looks like it to me

Bummer. Thanks Wantonamara.

Probably poison oak. But just as horrible.

Now, the quest to kill it. Ugh. Thanks Plantmaven

I have some also. How do people kill theirs.

Well Mara, you may not want to use Round Up, but when I lived on an acre not far from where I live now the place was overrun by poison ivy and I am highly allergic. I'd use loppers to cut it off at the bottom and spray the stump with RU. That way it didn't come back. My husband would haul it away. He wasn't allergic to it.

Probably the vinegar treatment discussed on another thread would take care of it..

Here is a link that might be useful: Health issues linked to RU

There is one way to kill that plant. Get yourself a gallon zip-lock bag. Make sure you are well protected before stuffing it into the bag. Then add stump killer and make sure it can drink the stump killer. As long as it has the liquid to drink it should drink until it dies all the way back.
It does need to be killed now before it takes over your fence. Take care in disposing the plant as all parts are poison. Round up will kill it back but will do nothing to the roots. Digging up the compete plant will slow it down but unless you get all of the roots it will come back.

Normally I leave it alone. There is not alot of it out here but I am getting some under a tree by the house.

I found this interesting site. It appears fairly in depth. Amonium sulphamate sounds interesting but is unavailable in the USA but available throughout Europe. Cheap and way less toxic.

Here is a link that might be useful: Poison Ivy be gone site

I had a patch under some oaks several years ago and like Roselee, I lopped it off then sprayed RU on the stems for several days in a row and it never came back.

There is an RU made especially to kill poison ivy.