As long as the tree roots present in the built up area are small, you won't be doing any damage to the tree. If you run into larger roots (pencil size plus), it wouldn't hurt to insure that they are cut cleanly (not torn) and that the cuts are left exposed (not reburied) for a while.

Brandon, what is the best way to kill the established ivy? With the grape vine I have I alternate between pulling it out of the walnuts and spraying round up on it and cutting the stems then tresting em with round up.

Any chance the english ivy is grafted into the tree and will share the poison?

'Any chance the English ivy is grafted into the tree and will share the poison?' Ivy is not a parasite and merely uses the tree as support. It obtains no nutrients from the tree. Make sure that all the ivy stems are cut through at the base of the tree and whatever is on the tree will die. Then you are only dealing with the part of the ivy growing on the ground.

Research shows that glyphosate, once translocated from the foliage down into the roots, does move through the rhizosphere to affect nontarget plants.

Duplicate...

This post was edited by rhizo_1 on Mon, Aug 4, 14 at 8:44

I killed a black locust by trying to kill poison ivy climbing up the tree. I carefully pried the vine away from the tree trunk, cut the vine in several places and dripped two drops of Tordon on the cut part of the vine. Both the tree and the vine died. Maybe it was a coincidence and my locust would have died anyway, but I'm taking the blame. I'd be very careful if I were you.

I misunderstood the OP - I thought they were asking if the the ivy ON the tree would absorb the herbicide. Many people think ivy is parasitic like mistletoe but it isn't. The roots beneath the tree are a different matter.

Significant translocation of glyphosate through soil is rare and most often occurs where excess concentration or over application is used. However, this is a different situation!!! The OP has already pulled up and exposed a bunch or roots. IMO, treating with glyphosate or other herbicide at this point is probably out of the question. Now, I'd probably just use repeated mechanical removal until the ivy gives up, or at least until it is significantly reduced and freshly exposed tree roots are not involved.

I would put a mulch down and when the ivy comes up, treat it with Crossbow. It kills ivy, clover, horsetail, and blackberries way better than RoundUp.
Mike