Are you following the advice in the Bermuda Bible? It was written by a lifelong Bermuda sod farmer, and is excellent advice for the homeowner with Bermuda. Google it!

It talks about fertilizer, what is a good fertilizer that I can pick up that has the 34-0-0 or 39-0-0?

I use ammonium sulfate (or sulfate of ammonium) on my bermuda lawn. It's 21-0-0, so you'll need to use a little more than 39-0-0. You want 1 lb of nitrogen per 1000 sq ft. Divide the first number listed on the bag of fertilizer (N) into 100 to calculate how much fertilizer you need in lbs. My lawn is almost exactly 1000 sq ft so I use almost 5 lbs (100 / 21 = 4.76 lbs). I have to say though, I'm not so sure that's your main problem. Are you sure it's getting enough water? Are you watering deeply and infrequently. If not what is your watering shcedule? How much sun does the corner get? Can you take a picture of the stringy weed and post it?

I'm with cwrebel on this. I'm ready to almost guarantee this is a problem with watering (too frequently) and shade (too much).

I've been working with a guy in Phoenix for years on his lawn. He's watering once per week and fertilizing with Milorganite and soybean meal every month or so. The lawn looks much better now but he has to do extra stuff to keep it that way. We're finally getting to the crux of the problem for him. He has most of the nutgrass out, but he's really resisting filling in a low spot in the front yard and transitioning to St Augustine in the back. This might be the year for him.