I know it doesn't look like "red-sided", but the Gartersnakes in this region are parietalis, not annectans, at least according to Werler and Dixon (2000) and the Herps of Texas website.
Daniel
27-Aug-2012 02:28
This is a Texas garter (T.sirtalis annectens), not a Red-Sided garter (T.sirtalis parietalis).