hi, i have a bunch of small buckthorn popping up and would like to chemically treat a large area with a sprayer. In fall 2022, i cut/painted the stumps with round up, which did a good job, but now on to round 2 with all the new growth. do you have a recommendation on triclopir vs round up? is now (late may) a good time to spray? what percent (concentration) active ingredient should i use when i mix the spray? (should i make it stronger than the label recommends)?