JACKS BRANCH (Stephens County). Jacks Branch rises a mile south of Eureka in southwestern Stephens County (at 32°33' N, 99°05' W) and runs north-northeast for six miles to its mouth on Pecan Creek, just east of Farm Road 1853 (at 32°37' N, 99°03' W). The creek traverses an area of rolling hills where clay and sandy loams support scrub brush, mesquite, cacti, and grasses.