Iowa Code § 200.13
The secretary shall publish at least annually, in such forms as the secretary may deem proper, information concerning the sales of commercial fertilizers, together with such data on their production and use as the secretary may consider advisable. The secretary shall report semiannually the results of the analysis based on official samples taken of commercial fertilizers sold within the state as compared with the analyses guaranteed under section 200.5 and section 200.6, together with name and address of the manufacturer or distributor of such commercial fertilizer at the time the official sample was taken. A copy of this semiannual report will be mailed by the secretary to each corresponding county extension director in the state.
Iowa Code § 200.13