"Auxiliary soil and plant substance" means any chemical or biological substance or mixture of substances or device distributed in this state to be applied to soil, plants, or seeds for soil corrective purposes; or that is intended to improve germination, growth, yield, product quality, reproduction, flavor, or other desirable characteristics of plants; or that is intended to produce any chemical, biochemical, biological, or physical change in soil; but does not include commercial fertilizers, agricultural minerals, pesticides, soil amendments except biochar, or manures. It shall include the following:
Ca. Food and Agric. Code § 14513