Every year I put down pre-emergent's and when the barrier gets broken from
the lawn service I get crab grass. So I was thinking since there is no way
to stop the seeds from germinating that the only way to get rid of it
permanently is to let the seeds germinate, then kill it with roundup BEFORE
the grass matures enough to produce and drop seeds.

Does this sound like a good way to get rid of it permanently? I figure the
challenge I have is that when it grows I don't stop it from maturing and
dropping seeds.

I know I'll have brown spots until I seed and water at the end of the
summer.

Thanks!

Eddie G