u/Honest-Anything8226

My yard has patches of these creeping weeds, which I believe are morning glory seedlings. Earlier this year, I killed all the existing grass and weeds with herbicide and then planted buffalo grass seed. The buffalo grass is now growing well and is about 1–2 inches tall, but these weeds have come back.

The weeds seem to have deep, extensive roots and are very difficult to pull by hand. Does anyone have recommendations for controlling or killing these weeds without harming the newly established buffalo grass? Any advice would be appreciated.