Section 73.6. Slowly available plant nutrients

(a) No fertilizer label may bear a statement that implies the presence of a slowly available plant nutrient unless the nutrient is identified on the label.

(b) If a fertilizer label implies that nitrogen is slowly available, for example, organic nitrogen, the guaranteed analysis shall indicate the percentage of water-insoluble nitrogen in the material.

(c) If the label states the amount of organic nitrogen present in a phrase such as ‘‘25% of the nitrogen from ureaformaldehyde (Ureaform),’’ the water-insoluble nitrogen guarantee may be not less than 60% of the nitrogen so designated.

(d) If the water-insoluble nitrogen is less than 15% of the total nitrogen, the label may not bear designations such as ‘‘organic,’’ ‘‘ureaform’’ or similar terms.

(e) The phrases ‘‘coated-slow release fertilizer’’ and ‘‘coated-slow releast’’ are acceptable descriptive terms for products for which a testing program has substantiated the claim. Water-insoluble nitrogen shall be guaranteed at 15% of the total nitrogen level for slow release materials.

(f) The Association of Official Analytical Chemists Test Method as prescribed in Methods of Analysis shall be used to substantiate the presence of slow release materials. It is permissible to eliminate grinding during sample preparation.

The provisions of this § 73.6 adopted July 28, 1972, effective July 29, 1972, 2 Pa.B. 1435; amended February 9, 1979, effective February 10, 1979, 9 Pa.B. 498. Immediately preceding text appears at serial page (6734).