I have planted Dymondia Margaretae between my walkway stepping stones. It has made a very durable and attractive mat without getting overgrown like grass. I have a 'weed' (see attached photo) that is starting to take over the Dymondia. It starts in an area and ends up making a complete mat. I have tried to pull it out but have not been able to effectively remove the root system as it continues to gain ground. SO, I plan to try a herbicide and apply it with a Q-Tip ONLY to the weed leaf(as I know that the Dymondia will die if I use the herbicides that I have on hand - see below - and spray it on). CAN YOU ID THE WEED? CAN YOU RECOMMEND A HERBICIDE THAT I CAN APPLY TO A TRIAL AREA ONLY ON LEAFS VIA Q-TIP TO SEE IF IT WILL WORK? THANKS.

Herbicides that I have on hand include (I can buy others if I must):

Ortho Weed B Gon Max plus Grabgrass control

Bayer Advanced All-In-One Lawn Weed & Grabgrass Killer

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