| I had the same problem here. I tried using round-up and just spot
treating the poison ivy leaves.
I had one of those long wands on my sprayer that I could reach the leaves with. It mostly worked. It stopped new growth but each year I saw it return ... just not as bad or as much as the previous year.
In the end, I just pulled that last remaining vines that seemed
determined to return. You have to be very careful not to miss
and spray the lilac or you will end up with a few dead branches. See the control section for more information. If you have any large
vines you can just cut segments out which will kill the top and use brush-b-gone and paint the lower segment.
I tend to take the slow road around here. I start by stopping any
new growth. Then in a few years I come back and remove the old
vines. I have found I am not as sensitive to the old dead growth .
If I only had a few plants or vines, I would just pull it. I
had more plants around this property than I could count so I have to take the slow road :) | 
