7 CFR § 810.1004 - Grades and grade requirements for oats.

Grade	Minimum limits—		Maximum limits—
	Test weight per bushel (pounds)	Sound oats (percent)	Heat-damaged kernels (percent)	Foreign material (percent)	Wild oats (percent)
U.S. No. 1	36.0	97.0	0.1	2.0	2.0
U.S. No. 2	33.0	94.0	0.3	3.0	3.0
U.S. No. 3 1	30.0	90.0	1.0	4.0	5.0
U.S. No. 4 2	27.0	80.0	3.0	5.0	10.0
U.S. Sample grade—
U.S. Sample grade are oats which:
(a) Do not meet the requirements for the grades U.S. Nos. 1, 2, 3, or 4; or
(b) Contain 8 or more stones which have an aggregate weight in excess of 0.2 percent of the sample weight, 2 or more pieces of glass, 3 or more crotalaria seeds (Crotalaria spp.), 2 or more castor beans (Ricinus communis L.), 4 or more particles of an unknown foreign substance(s) or a commonly recognized harmful or toxic substance(s), 8 or more cocklebur (Xanthium spp.) or similar seeds singly or in combination, 10 or more rodent pellets, bird droppings, or equivalent quantity of other animal filth per 1 1/8 to 1 1/4 quarts of oats; or
(c) Have a musty, sour, or commercially objectionable foreign odor (except smut or garlic odor); or
(d) Are heating or otherwise of distinctly low quality.

1 Oats that are slightly weathered shall be graded not higher than U.S. No. 3.

2 Oats that are badly stained or materially weathered shall be graded not higher than U.S. No. 4.