Sorry Woodchux, no magic spray known here, and the roots are often just too involved with the "host" for a heavy killer like roundup, but then I'm no spray tech.
However, I DO have a strategy! After several laborious attempts at stripping live, green English Ivy, I gave that nonsense up. No one has enough money to cover the hours and hours that takes. We're talking trees that have English Ivy going fourty, fifty feet up, stalks the size of your forearm.
What you have to do is set up the ivy removal as a two visit job. First visit, cut the stalks at the ground level, then again three or four feet up the trunk and sever it vertically in sections to clear off the flare. This to make sure you get all interconnecting stalks all cleared off at the base. If it is massively thick and green, climb the tree with your hedge shears and take off everything your shears will handle. Top handle saw will do the job, but nice long shears are much faster. Don't get crazy, I've never seen it happen but I imagine a sharp set of shears could sever or badly damage a loaded climbing line.
Step two is wait a
minimum two weeks, a month is much better. The customer has to have faith in you here...
Finally, now that this Ivy is getting dry and brittle the fun begins! Get your rope in well above the Ivy and peel and trim it off the trunk and branches by hand until you get mats of it folding away, don't cut the mats off! Get back above the mats and just start STOMPIN!
Do it right and the nasty, intertwined nature of the Ivy starts to help you. Insert you handsaw just here and there to get the mat folding away around branches, but mostly just go nuts stomping and peeling huge sheets of Ivy off with your feet.
I used to hate English Ivy removals, now I (almost) look forward to the chance to just go ape while dangling from my rope.
Somebody will probably chime in with a good chemical killer for Ivy, so much the better. But, you still have to get the strangulation off the tree, so I hope you enjoy my method as much as I do.
RedlineIt