Yes, of course. But I'd spray or at least coat myself with Dawn Dishwashing liquid before I went into the battle with PI.

Not really, and the waxy leaves of ivy repel most herbicides. Standard removal from trees: "First remove ivy from trees and then remove ivy from the ground. If you don't remove it from the ground, it will just grow back up on the trees. trees - Depending on the thickness of the vines, use either loppers or a pruning saw to cut through each vine at shoulder height and at ankle height. Be careful not to wound the bark of the tree when cutting the ivy vines. Strip the ivy away from the tree between the two cuts (some vines may be so big that you will need to pry them away from the tree). Be careful not to damage the bark. Next start pulling up as much ivy as possible and as deep as possible around the base of the tree. Keep extending the pulled area around the base of the tree until the pulled area is at least six feet from the tree's base all the way around"

I have news about the ivy. Two things have changed in the two years since I cut all the ivy trunks around the tree. First, I got a new tool, a vibrating multi-tool, that makes it incredibly easy to cut through the vines. I had previously used a little curved hand saw that was difficult to use on the tough trunks. Second, this venue was so focused on finding a missed bit of ivy that it made me doubt my own certainty that I had done a complete job. I went back to the tree, this time with my new tool. I went around the tree, cutting all the trunks evenly at about six feet high, near the top of my reach. To be clear, there are about 7 to 10 trunks the size of a silver dollar or larger, and there are also maybe twice as many that are smaller. To give an idea, at one point, high up in the tree, the ivy began growing downward, like the vines Tarzan used to swing around the jungle. When we bought the house, it was maybe 10 feet off the ground, and swayed widely in the wind. Over the next 30 years, it grew downward to reach the ground with a vine the thickness of a broom handle. The old tool was a curved saw and it was a difficult tool to use in the tight nooks and crannies. The new tool made it easy to make several cuts, as needed, just to completely clear out the mess. In the past two years, the vegetation on the ground has changed a little and so it was a bit easier to see what was going on. The big change, however, was the new tool. In the end, I did find one small bit of ivy, maybe the diameter of a quarter, that was snaking through the middle of two twin trunks. I really had my fingers crossed as I cut that one bit that looked to be the culprit. It worked! I wanted to wait to be sure, but the ivy is now clearly almost dead. There are very few remaining green leaves, a few more remaining brown leaves, and on the ground, it looks more like fall than springtime. What I find amazing is that the small single ivy trunk that I missed was able to supply the entire plant with it's needs for a connection with the ground. I literally took away probably 95% of it's trunk system, leaving only one small connection. I might have thought that the different entwining trunks would each supply one portion of the plant. Instead, that single point of connection to the ground seems to have found a way to share it's connection with all the other disconnected trunks arising toward the sky. Where the ivy trunks were deeply intertwined, I think that they must have somehow grown together, such that they were sharing resources. When all but that single small trunk was severed, that single small trunk was somehow able to provide enough for the entire, huge mass of airborne leaves, and was able to connect with the other trunks which had clearly been severed. These trunks were on all sides of the tree, but sort of interwoven. Still, that means that water from the single remaining trunk somehow connected with other trunks, which then went on to connect with even more trunks until the entire plant was again connected to the ground! That is one tough plant! I do recall this scenario at the time of the original cuts, two years ago. At first, the ivy began to die, a little. Some leaves turned yellow and fell off. I was expecting it to continue all the way, as I had seen many times. Yet, somehow, after a few weeks of losing leaves, the loss of leaves stopped, and then the worst thing happened: new growth was obvious! So the story ends like this: yes, there was a single, small missed piece of trunk. With my new tool, I really cleaned up the trunk of a lot more deadwood, and in the process, was able to cut that final missed piece. The loss of that final connection to the ground now has the entire ivy nearly dead. Having that success with the tree closest to my home, and easiest to explore, I geared up to re-visit the Douglas Fir. It is on a steep slope, and difficult to approach. Again, I think I may have found one, tiny missed trunk, and I severed it. I also cleaned up a lot so that the ivy trunks were easier to visualize. It has not been as long since I made the new cuts, but it does seem that the leaves are in the very beginning stages of turning brown and falling off. Fingers crossed! Time will tell, but I think I have finally finished a job I began two years ago, and I'm ultimately relieved.

MIke, most of the ivy that populates the PNW is Irish ivy, Hedera hibernica. But it is very similar to and almost impossible to differentiate from English ivy, Hedera helix. And has an almost identical growth habit. When growing "wild" here, it tends not to smother the trees it grows on, simply because it doesn't get that tall. 60-80' up for sure but not much above that. And the Doug firs that seem to be a preferred host can easily get double that. But I have seen it engulf a disused or abandoned garden and climb much smaller growing ornamental trees and smother them. And dozens of large shrubs. In fact, a neighbor has a large (20'+) rhododendron in a yard she no longer bothers to maintain and it is being rapidly consumed by the ivy. And blackberries........both likely 'planted' by visiting birds.