The Upper Coastal Bend Boll Weevil Eradication Zone shall consist of the following area: all of Austin, Brazoria, Colorado, Fort Bend, Jackson, Matagorda, and Wharton counties, and that part of Waller County lying south of State Highway 159 from the Austin County line north and east to Hempstead, then east on State Highway 6/290 to the Harris County line.
4 Tex. Admin. Code § 3.117