I see this problem frequently with new construction, usually because rye is often used for soil retention prior to sodding, but the scenario is still very similar. It is also one of the reasons I've developed a disdain for rye. 1) Don't use an herbicide right now. This may be hard to swallow as I imagine you used Annual Rye and it is growing like the weed it is, but your lawn is not established enough to use an herbicide strong enough to kill the rye. For now, keep it mowed down short, and keep it watered until it roots. 2) Again, no herbicide. I love Celsius WG and have used it since it hit the market. It is a great product, and will be useful for you at some point, but under the label restrictions it clearly warns to "use this product on established turf only," and this isn't just to skirt damage claims, the warning is there for good reason. 3&4) "Scalping" is done during dormancy and topdressing is done during active growth. Keep in mind a scalping is just the pruning off of last season's dead growth, so if your sod didn't grow the scalping need should be fairly light. Also, consider rolling the lawn with a water filled drum to smooth it and insure that the roots are making good contact. The fact that it didn't grow after being put down concerns me, as sod is vulnerable to dehydration until it roots. 5) Yes, to an extent. Bermuda is one of the more hardy grasses so I've never seen it killed by scalping it. However, I have seen it stunted by scalping it during the growing season. So again, cut it down now and top-dress later. When it's actively growing, the root system pulls water primarily through a process call Transpirational Pull, which is the release of water through the leaves that creates a pull through the capillaries that reach all the way to the root system. When an actively growing leaf is removed, it interrupts this process and reduces the root systems draw on the soil moisture. Also, make sure to apply a good starter fertilizer this Spring to encourage the root system to root as quickly as possible. Once it is established and you're mowing regularly, you can go after any lingering ryegrass or other weeds without worry. Just remember to always check label restrictions. Here is a link that might be useful: .

Are you going to be happy with the results? Overseeding into an existing stand will result in a hodgpodge lawn of different shades, textures and growth rates. A complete reno may be your best recourse. For best overseeding results: Scalp the lawn. Run a verticutter over the lawn and rake up the debree. Spread your elite KBG seed and then run the verticutter set at a 1/4" depth over the lawn twice at 45 degree angle to each run. This will cause almost as much damage to the lawn as a complete kill and reno, but will result in very good germination of the new seed. Optionally topdress with peat moss. Drop a starter, water appropriately and mow carefully to keep any surviving extablished grass from out-competing the new seed. Good luck.

Reseeding bermuda is not really done in the spring either. You will see a lot of advertising and see giant bags of bermuda seed starting in February but resist the urge. Bermuda seed takes best when the soil is very hot...as in July. What kind of bermuda do you have now? If you have a sodded variety I would suggest you do not seed it under any circumstances. Seeded and sodded varieties are like two different plants. If you mix them, it will always look weedy.

just overseed. there will be a lil brown for 2-3weeks, but the new grass will get going