This plant was locally common in loose sandy loam soils of the dry lake bed of Lake Travis at several of the LCRA parks visited today, both in Travis and Burnet Cos.
The plants were from 1 to 3 ft tall/wide. The larger stem leaves were >10 cm long.
I'm going to add a common name for this, just because it's so cool: "Hogwort" (from the North Central Flora).