Answer: Round Up is a vegetation killer - if you use it on your lawn, you will kill the lawn as well as the weeds. If you have more weeds than turfgrass you might want to start all over with a clean slate by rototilling everything up. Or, you can try to rehabilitate your turf by killing the weeds and then overseeding. In Spokane, Kentucky Bluegrass or Perennial Rye are the turfs of choice. WSU cooperative extension has lots of publications for managing home lawns. Here's their website:
You can click on the various links for help in choosing and maintaining turfgrasses. Good luck with your lawn!
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