There is a small section of my field that I want to plant with the RR corn, I have the seed. There are already alot of weeds (pigweed mostly, and some grasses) that have germinated in the last few weeks. Should I disk it and plant immediately? Or should I disk it and wait a week or two to give the dormant seeds to start germinating, then plant the corn, and then spray roundup on any weeds that have emerged? I have a 10' boom sprayer and a 2 row planter, so planting/spraying is not a problem.

I'm basically asking if I should give the weeds a head start before roundup, or start with a clean disked ground and spray when the corn/weeds are a few inches high.

The value of RR corn is that you can plant it and spray it after the weeds are up. I'd say get it in the ground. Then spray the weeds later so that you get them all, not just the earlier germinating ones.

Spray now, wait two weeks, disk, plant corn, wait 4 weeks, spray again. You want as much weeds and grass dead as possible.