Sticking with weed killers, and a product I HATED using...........
https://www.syngenta.com.au/product/.../sprayseed-250
That stuff is vile, probably the most toxic product I have ever used and one that hopefully wont haunt me in my later years.
This stuff is similar to Slasher in that it burns the foliage and will burn your skin as well. A colleague once got it close to his eye and caused him unimaginable grief. I would say never, ever use this if you have the choice.