Nebraska has spent a long time in the severest drought category available, with no sign of let up. On the Plains we should be accustomed to such boom and bust cycles of moisture. Below is an image of some native plant root depths -- click on the image to expand.
Further benefits include keeping soil in place while increasing soil fertility (which means less fertilizing), groundwater purification and storm water management, carbon sequestration, and of course the big one: major benefit to wildlife. Wait, and this: a lower maintenance garden that's thriving. Oh shoot, have another: when I'm standing in my garden as compared to my lawn, it actually feels a few degrees cooler (I'm serious).