As the title mentions, this is an Texas Blue Indigo snake
The Texas Blue Indigo (Drymarchon melanurus erebennus) is a Protected, non-venomous snake native to Texas and portions of Mexico.
It is one of the largest snakes in North America.
The Blue Indigo its massive size (6-8' in length, though I've seen one very close to 10') and overwhelming strength to kill their pray using brute force and their powerful jaw strength (ie: not a constrictor).
They frequently eat rattlesnakes, and we highly endorse that, especially around the house and barn areas!
If you see one, count yourself lucky! With the rapid growth in South Texas, 95% of their home range here has been disturbed and threatened, sadly.