(a) Name. The name of the viticultural area described in this section is “Texas High Plains.”

(b) Approved maps. The appropriate maps for determining the boundary of the Texas High Plains viticultural area are six U.S.G.S. topographical maps of the 1:250,000 scale. They are titled:

(1) “Clovis, New Mexico; Texas” 1954, revised 1973.

(2) “Brownfield, Texas; New Mexico” 1954, revised 1973.

(3) “Hobbs, New Mexico; Texas” 1954, revised 1973.

(4) “Plainview, Texas” 1954, revised 1974.

(5) “Lubbock, Texas” 1954, revised 1975.

(6) “Big Spring, Texas” 1954, revised 1975.

(c) Boundary. The Texas High Plains viticultural area is located in Armstrong, Bailey, Borden, Briscoe, Castro, Cochran, Crosby, Dawson, Deaf Smith, Dickens, Floyd, Gaines, Garza, Hale, Hockley, Lamb, Lubbock, Lynn, Motley, Parmer, Randall, Swisher, Terry and Yoakum Counties, Texas. The boundary is as follows:

(1) Beginning on the Hobbs, New Mexico; Texas, map at the intersection of the Texas-New Mexico border and U.S. Route 180 east of Hobbs, New Mexico;

(2) The boundary follows U.S. Route 180 east through Seminole, Texas and onto the Big Spring, Texas, U.S.G.S. map where it intersects with the 3,000 foot contour line in the town of Lamesa, Texas;

(3) The boundary then follows the 3,000 foot contour line in a generally northeasterly direction across the U.S.G.S. maps of Big Spring and Lubbock, Texas;

(4) The boundary continues along the 3,000 foot contour line onto the map of Plainview, Texas, where it follows a generally northwesterly direction until it intersects with State Highway 217 approximately 12 miles east of Canyon, Texas;

(5) The boundary then follows State Highway 217 west to Canyon, Texas, leaves State Highway 217 and proceeds in a straight line in a northwesterly direction until it intersects with U.S. Route 60, still within Canyon, Texas;

(6) The boundary then follows U.S. Route 60 in a southwesterly direction onto the U.S.G.S. map of Clovis, New Mexico; Texas, where it intersects the Texas-New Mexico border;

(7) The boundary then follows the Texas-New Mexico border south, across the U.S.G.S. map of Brownfield, Texas; New Mexico, to the beginning point on the Hobbs, New Mexico; Texas, U.S.G.S. map.