The Southern Blacklands Boll Weevil Eradication Zone shall consist of the following area: all of Anderson, Brazos, Burleson, Freestone, Grimes, Harris, Houston, Leon, Liberty, Madison, Robertson, Walker, Camp, Wood, Upshur, Marion, Harrison, Gregg, Smith, Cherokee, Rusk, Panola, Shelby, Nacogdoches, San Augustine, Sabine, Angelina, Trinity, San Jacinto, Polk, Tyler, Jasper, Newton, Hardin, Orange, Jefferson, Chambers, Galveston, Washington, Montgomery, Coryell, Mills, Lampasas, San Saba, Llano, Gillespie, Kendall, Blanco, Burnet, Bell, Williamson, Travis, Hays, Comal, Guadalupe, Gonzales, Fayette, Caldwell, Bastrop, Lee, Milam, and Falls Counties; that part of Limestone County south of Highway 84 from the McLennan County line east to the Freestone County line; that part of Waller County north of Highway 159 from the Austin County line north and east to Hempstead, then east on Highway 6/290 to the Harris County line; and that part of McLennan County south of Highway 84.