4 Tex. Admin. Code § 9.4
The department hereby adopts by reference Rules for Testing Seeds of the Association of Official Seed Analysts, as to procedures, methods, and tolerances for seed testing, except that in enforcement, no tolerance will be allowed for balloonvine, castorbean, field bindweed, hedge bindweed, itchgrass, serrated tussock, or tropical soda-apple. A tolerance of one will be allowed for cocklebur. A tolerance of one will be allowed for nutsedge tubers in a two-pound sample. If nutsedge tubers are found in excess of this tolerance, an additional 50 pounds will be required for testing. The tolerance of one nutsedge tuber will be allowed in this 50-pound sample. The tolerance allowed for pure live seed will be the same as for germination. A laboratory test used for labeling purposes must be made by the department, the official state seed laboratory of another state, or a Registered Seed Technologist/Society of Commercial Seed Technologist member laboratory. Information relative to obtaining copies of the material adopted by reference may be obtained by contacting the Texas Department of Agriculture, Seed Quality Program, P.O. Box 629, Giddings, Texas 78942. A copy is also available for public inspection at the Texas Department of Agriculture, Seed Quality Program, W. H. (Bill) Pieratt Building, Giddings, Texas.
4 Tex. Admin. Code § 9.4