(a)Name. The name of the viticultural area described in this section is "Texoma". For purposes of part 4 of this chapter, "Texoma" is a term of viticultural significance.(b)Approved Maps. The appropriate maps for determining the boundaries of the Texoma viticultural area are two United States Geological Survey, 1:250,000 scale, topographic maps. They are titled:(1) Sherman, Texas; Oklahoma, 1954, revised 1977; and(2) Texarkana, Tex.; Ark.; Okla.; La., 1953, revised 1972.(c)Boundary . The Texoma viticultural area is located in Montague, Cooke, Grayson, and Fannin Counties, Texas. The boundary is defined as follows:(1) The beginning point is the northwest corner of Montague County (at the Red River, which is also the Texas-Oklahoma State line) on the Sherman map. From this point, the boundary line:(2) Follows the Red River eastward along the Texas-Oklahoma State line, passes onto the Texarkana map, and continues to the northeast corner of Fannin County; then(3) Continues southward along the eastern Fannin County line to a point approximately three miles west of Petty, Texas, where a power line shown on the Texarkana map crosses the county line; then(4) Continues southwest in a straight line for approximately 13 miles to the intersection of State Routes 34/50 and State Route 64 at Ladonia, Texas; then(5) Follows State Route 34 west to its intersection with State Route 68; then(6) Continues west-southwesterly in a straight line from that intersection to the intersection of U.S. Highway 69 and State Route 78 at Leonard, Texas, on the Sherman map; then(7) Continues northwest on U.S. Highway 69 for approximately 6 miles to the intersection of U.S. Highway 69 and State Route 121 at Trenton, Texas; then(8) Continues westerly in a straight line to the intersection of State Routes 160 and 121, and then continues west on State Route 121 to its intersection with U.S. Highway 75 at Van Alstyne, Texas; then(9) Continues south along U.S. Highway 75 to the Grayson County line; then(10) Continues west along the southern Grayson County line and then the southern Cooke County line to the county line's intersection with Interstate 35; then(11) Continues north along Interstate 35 to its intersection with State Route 922 in Valley View, Texas; then(12) Follows State Route 922 west for approximately 17 miles to Rosston, Texas; then(13) Continues west-southwest from Rosston in a straight line for approximately 19 miles to the intersection of U.S. Highway 287 and State Route 101 at Sunset, Texas; then(14) Follows U.S. 287 northwest approximately 17 miles to the western Montague County line; and(15) Continues north along the western Montague County line to the beginning point at the northwest corner of Montague County.T.D. TTB-38, 70 FR 72716, 12/7/2005