21—40.7 (199) Labeling of seeds with secondary noxious weeds. In addition to the labeling requirements for all agricultural seeds, such seeds containing secondary noxious weeds shall contain on their labels, the following information:
The name and approximate number of each kind of secondary noxious weed seed per pound in groups 1, 2, 3 and 4 below, when present singly or collectively in excess of:
	  1. 	 Eighty seeds or bulblets per pound of Agrostis species, Poa species, Bermuda grass, timothy, orchard grass, fescues (except meadow fescue), alsike and white clover, reed canary grass and other agricultural seeds of similar size and weight or mixtures with this group.
	  2. 	 Forty-eight seeds or bulblets per pound of rye grass, meadow fescue, foxtail millet, alfalfa, red clover, sweet clover, lespedeza, smooth brome, crimson clover, Brassica species, flax, Agropyron species and other agricultural seeds of similar size and weight or mixtures within this group or of this group with 1.
	  3. 	 Sixteen seeds or bulblets per pound of proso, Sudan grass and other agricultural seeds of similar size and weight or mixtures not specified in 1, 2 or 4.
	  4. 	 Five seeds or bulblets per pound of wheat, oats, rye, barley, buckwheat, sorghum (except Sudan grass), vetches, soybeans and other agricultural seeds of a size and weight similar to or greater than those within this group.
All determinations of noxious weed seeds are subject to tolerances and methods of determination prescribed in the rules and regulations under this chapter.