Okla. Stat. tit. 2, § 2-8-26.1: State preemption – Exception for taxation

A. The Legislature hereby occupies and preempts the entire

field of legislation in this state touching in any way the

regulation and enforcement of the registration, labeling, sale,

storage, transportation, distribution, notification of use, and use

of seeds to the complete exclusion of any order, ordinance or

regulation by any municipality or other political subdivision of

this state.

B. No political subdivision shall regulate the registration,

packaging, labeling, sale, storage, distribution, use or application

of seeds. No political subdivision shall adopt or continue in

effect local orders, ordinances, or regulations in this field,

except for those relating to taxation relating to registration,

packaging, labeling, sale, storage, distribution, use or application

of seeds. Local legislation in violation of this section is void

and unenforceable.