At this size, you don't have much in the way of herbicide options and mechanically cultivating, pulling the weeds, or covering with newspaper and mulch are your best options. 2,4-D is used on very small corn, but tends to cause the stalks to bend and makes them brittle once the corn is over a few inches high. Last thing you want is to have the stalks break off just when the ears are almost ready to eat! You can apply it if you keep your spray nozzle very low and try to minimize how much gets onto the base of the stalks, but you may still end up with some brittle ones that will break in the wind. Tomatoes are very sensitive to the vapors of 2,4-D as are some other broadleaf garden vegetables, so don't use if they are near. Other broadleaf herbicides available to homeowners will also likely damage the corn at this stage. Grass killers will also kill your corn, they are out. The herbicide version of Preen contains trifluralin, which kills weeds when they germinate. If you cleaned the weeds out, you could put it down to prevent future flushes of weeds. Just mix it into the top inch or so of soil or water it in with about 1/2 inch of water. Trifluralin is sensitive to sunlight and degrades quickly if not worked into the soil. Corn is sensitive to trifluralin and it will stunt the roots if the corn is planted in treated soil. Once it is emerged and growing, it shouldn't affect the plants but I've never tried that and you might find out otherwise. In a raised bed, I'd just pull the weeds when the soil is moist, then put down a good layer of mulch to prevent future ones. Good luck!

I'm sure the master texas_weed already covered your questions, but Celcius was a god send for me. This is the first year I'm properly taking care of my bermuda, nothing was done since it was sodded 2 years ago. Weeds were insane, especially Dallisgrass & Poa plus my neighbors yards are covered in weeds. Celcius knocked it all out within 2 weeks after one application but I did go a little heavy on application so got a little yellowing but nothing major.. and yes you will save money, if you break it down its about 50% cheaper than any big box store product(kills more types of weeds as well). Make sure you use an surfacant of some sort, I just used a standard non-inonic, but I hear MSO has benefits but someone else would have to chime in about that...

Here is the SDS for Celsius WG https://www.backedbybayer.com/~/media/BackedByBayer/msds/en/Celsius_WG_Herbicide.ashx If you have health and safety concerns call the number on page 1.

I also struggled big time last year with my fall seeding for the reasons you mentioned - I'm in Greensboro by the way. Typically it goes a lot smoother, but Mother Nature sometimes throws a curveball. I have not yet tried seeding in February, though I may give it a shot this year due to a Poa infestation. My back yard is shaded and so that will help with the heat and also with weed control, Bermuda and Crabgrass don't thrive there. Tenacity is a selective pre-emergent in the sense that it will not affect Fescue and KBG germination, but it is also very limited in what weeds it will prevent. For example, Bermuda is not listed on the label as . You would need to use Tenacity at seeding time and every 20 days thereafter until it's safe to use a serious pre-emergent like prodiamine, typically 60 days from germination. Then apply prodiamine for the summer. If you're not seeding, then go directly to prodiamine applied in March at the 5 month rate. It's kick-ass.