The poison ivy crop sure is healthy around here. When we moved in to our little house by the edge of the woods, poison ivy was growing up the trees in thick, hairy vines. Dave donned his Tyvec suit (very fashionable), chopped through it with an ax and threw it deep into the woods. Knight in shining armor stuff here, as far as I'm concerned, because I am pretty darn allergic to the stuff.
I have followed up with more chemical weed killer than I would like to admit, but make no apologies. When your kid starts to blister from the stuff, you do what you need to do. I have, however, been experimenting with a more natural weed killer. So far, the results have been really good and I will keep a bottle of my concoction with me in my gardening bag from now on. It seems to kill most anything you spray it on, so spray carefully. But the good news is that I don't worry to much about my "helpers" helping me.
4 c. white vinegar
1/2 c. salt
16 drops liquid dish washing soap
Spray on plants liberally. Repeat every couple of days if needed, or after a rain.