Thank you for the follow up. I fertilized once, a month ago with a fertlizer formulated for Texas- Lesco 15-5-10. I added impact sprinklers on timers 3 weeks ago, 40 minutes every 3 days. It has been 102F the last 11 days, fyi. I have not been mowing to keep the 2inch height it has remained the last 3 weeks.

I guess my question would be, under natural conditions, how long would you estimate a 2-foot square dead spot to recover to lush after round up?

The weeds were a mixture of dense broadleaf that just seemed to be best handled by going nuclear in a dozen spots about 2 feet wide and 2-3 feet long.

I suppose the high heat slowed the activity and it is just very slowly closing the gaps?

With temps above 100 you should be watering deeply once every 5-7 days. With impact sprinklers that might mean you have to water for 4-6 hours in each watering zone. Here's more on watering.

Watering: Deep and infrequent is the mantra for watering. This is for all turf grass all over the place. Deep means 1 inch all at one time. Put some cat food or tuna cans around the yard, and time how long it takes your sprinkler(s) to fill all the cans. Memorize that time. That will be the time you water from now on. My hose, sprinkler and water pressure takes 8 full hours to fill the cans. Your time will likely be less. I like gentle watering. As for watering frequency, that depends on the daytime air temperature. With temps in the 90s, deep water once per week. With temps in the 80s, deep water once every 2 weeks. With temps in the 70s, deep water once every 3 weeks. With temps below 70, deep water once a month. Note that you have to keep up with quickly changing temps in the spring and fall. This deep and infrequent schedule works in Phoenix and in Vermont, so it should work for you. The reason for deep and infrequent is to grow deeper, more drought resistant roots and to allow the soil to dry completely at the surface for several days before watering again. If it rains, reset your calendar to account for the rainfall.

2 inches is too high for bermuda to become dense. Thin bermuda allows weeds to get started. Reset your mower to the lowest setting to get it to thicken up. If you get scalping, we can help you with that.

For broadleaf weeds the best approach is to use Weed-b-Gon or Weed-b-gon Chickweed, Clover, and Oxalis Killer. There's no danger of that stuff killing the bermuda. The WBG CCO is the nuclear option for those broadleafs.

Give it at least 6 weeks, 10 in this heat

Thanks to all. I'll give it time and better measure watering. As far as cutting, I have the mower raised all the way up. Seems the only way to keep it lush green. When I lower it the grass browns. I never scalp it, just thought Bermuda liked to be cut tall to protect the roots from scorching sun. Thanks for the input.

I had good results using info provided by both dc and reeljake. You can feed your bermuda to force growth. I feed every two weeks and have gotten some really good results. If you are allowing your lawn to grow upwards of two inches, that it where it is using the energy. The lower you mow, the further your lawn will spread, if given the proper amount of food and water. If you can afford to add in a growth regulator (Primo Maxx or T-Nex) your lawn will get really thick and spread fast.

It seems counter intuitive but it really works. The grass has to exert energy, when you limit the upward growth, it uses the energy to grow laterally.

Bermuda is the one grass type that runs counter to your intuition. The seed won't even sprout until late June to July in most of the country. It loves the heat.

Got that right, Bermuda does not want it's roots shaded in any way. Unfortunately I've heard that 'shade your roots' thing for years down here in St. Aug land. Does not apply to Bermuda at all--Full sun & 110F is right where it wants to be.