Best HEAT and DROUGHT tolerant cover crop

[SMT1994]

For reference we’re in the Texas panhandle, south of Amarillo- Lubbock to be exact. The summers here seem to get more brutal every year, with all of July this year being over 95F every day, with the last part of June staying 105F up to 110F. It’s just miserable. Our winters aren’t usually terrible, but we can occasionally get a freak week with single digits and wind- although that’s not typical and high twenties with little precipitation are more typical I need an option for a grazing pasture/cover crop that will LIVE THROUGH THE SUMMERS. Everything just dies, even with deep watering in the establishment stages. In the fall we have good success with wheat and a chicks mix that has radish and some other stuff, but once March hits it’s a race to keep anything alive while the awful heat and lack of rainfall come in quickly. So, it’s not as important for me that the crop will live multiple years, as I don’t mind planting something different for fall/winter, as it is more important that the crop is drought and heat hearty so that it is prolific enough for grazing in the hot months! Thanks!

 

[DotToDot]

I know this isn’t exactly what you’re asking, but what are you doing for your chickens to keep them cool?

 

[SourRoses]

Chia seed is one of the only things I can think of. It's hard to meet all of your requirements because most things that can survive drought are not considered crops, nor do they grow quickly.
Anything you do plant will have to start in spring and get nice and established before the drought begins. Having deep roots and tough woody growth is a big part of how such plants survive. You would need to water it if there is not enough rain in spring.

But the nice thing is that established plants help keep moisture in the soil through shade and structural support. So I would do a mixed planting with choices included just to support the area.
First thing are trees. There are some very fast growing ones, Poinciana are the first that come to mind, as they can reach mature status in just a few years. You could buy them partly grown and nurse them in pots until spring. Trees do the most good when arrayed towards the afternoon sun. You could design the area so there's a meadow of sorts in the center.
Next come the bushes. There are a lot of tough bushes, some just for a barrier and some for food. I would pick a variety of tough ones. Bushes would do the most good in a line at the outer edge in the direction your water runs off from minor floods. Of course the water above the soil will still run off, but what's absorbed beneath the surface will be held back by an established root structure and contribute to your property.
Even some tough flowering plants can help, Zinnia (original, not fancy) is the only thing I've had impress me with it's toughness through Florida summers.

Once you've brought life back to the soil, it will be a lot easier to grow something that constitutes a crop.
I would look for a source of leaves and mulch in your area. There was some service recommended on here once where you sign up to have free mulch / tree trimmings dumped at your place by arborists and the like. Forget what it's called. You need a lot of organic matter to help keep the moisture in place.

Have a look at what's grown in Mexico in the same growing zone as you. That's why I suggest Chia, because I know it's tough and grown where it's arid.

Just about anything is still going to need some water, it's more a question of how often. So you may have to rig up some irrigation, but if you need to conserve there are some options like drip or plant specific waterers.