You can refer to our IPM report (page 12) from a few years ago for suppression control. The challenge will be that it is in the grass, but unfortunately to gain control you may need to kill off those sections with plans to re-seed once its managed. We are getting into the time of year to effectively spray for it. The chemical names listed will most likely only be available for professionals, but you can still search for active ingredients at a home improvement store or online.

As to not have to wait a 3 year period of constantly spraying chemicals, you could also attempt to dig up those areas and try to get as many roots as possible. Unfortunately if there are roots left, it will re-grow. Possibly a combinations of digging, replacing soil, and re-seeding or sodding those sections and then target spraying any plants that pop back up could be a more manageable project. 

Let us know if we can offer more assistance. 

Emily