comments:
Try actual glyphosphate. Mix per label in 32 oz spray bottle (Zep are good), every yard needs some. https://a.co/d/07UMeX7C
I use Glyphosate concentrate (41%) on Nandina. Something like this (Amazon link) but in a dropper bottle. Cut the stem like 6" above the ground (so you can keep track of where it is/was), and make the cut mostly horizontal (so the herbicide pools on the cut and doesn't run down the stem). Apply to the fresh cut, wait a minute for the plant to "drink" down the herbicide, then apply some more. If you have a big area of it, just do this for each stem, repeat a few times, the more the better. It's not perfect, I get about 50-75% success rate with this method out in the field - but if it's in your yard it's easy enough to just keep an eye on it, and hit it again if it starts regrowing in a couple months. Glyphosate is not soil active and will not harm nearby plants