I keep trying different things... Last year I used a 2%crossbow solution doing a broadcast spray from an ATV. It seemed to set them back last year, but I didn't think it killed them as that field is full of them again this year. This year I've treated a spot with a 5% tryclopyr solution with a backpack sprayer that I did a better job wetting all the leaves and I'm waiting to see the results.. I also did some basal bark treatment with 5% tryclopyr and diesel. Again, waiting to see the results..
For dormant stem basal bark, I plan to use 25% remedy/75% diesel but didn't get to it this past winter..
I'm certainly open to input on this, I'm no expert.
Someone told me Pastureguard so I assumed using Tryclopyr would be sufficient.