Iowa Administrative Code
Agency 21 - Agriculture and Land Stewardship Department
Chapter 43 - Fertilizers and Agricultural Lime
Rule 21-43.23 - Review of Product Registrations

Fertilizer and soil conditioner registrations may be reviewed to determine that the product meets claims for which registration was granted. If credible cause can be demonstrated that product claims have not been substantiated, registration may be canceled and a provisional registration may be issued until minimum requirements for registrations of fertilizers and soil conditioners again have been satisfied.