preparing for sod

I am preparing @ 350 + sq.ft.of earth for sod. Scattered throughout that area are these grass plugs of what looks like bahia grass,and when I till/ariate the earth with a hand tiller they come up easy enough. The tines on this tiller are about 5-1/2 inches long. My question is this: How deep do those roots run on those grass plugs? Do I need to spray round up on those plugged areas to? another words I would hate for them to over take/strangle the sod roots. Or, will cleanly pulling them up be just fine?
Thank you

I'm not familiar with that type of grass, but if it is a plant that would take over your new lawn, then I sure use the Round-Up. I'd wait a couple of weeks or so to see if any new sprouts came up of seeds, then spray again. You might have to repeat this more times.