(1) Plant nutrients, other than nitrogen, phosphorus and potassium, when mentioned in any form or manner shall be registered and shall be guaranteed on the label. Guarantees shall be made on the elemental basis. Sources of the elements guaranteed shall be shown on the label. Proof of availability shall be provided the director upon request. Except guarantees for those water soluble nutrients labeled solely for hydroponic or continuous liquid feed programs, the minimum percentages which will be accepted for registration are as follows:

(2) Guarantees or claims for the plant nutrients listed in subsection (1) of this section are the only ones which shall be accepted by the department. Proposed labels and directions for the use of the fertilizer shall be furnished to the department with the application for registration upon request. Any of the above listed elements which are guaranteed shall appear in the order listed immediately following guarantees for the primary nutrients of nitrogen, phosphorus and potassium.

(3) A warning or caution statement may be required on the label for any commercial fertilizer containing more than 0.1% boron or more than 0.001% molybdenum. The following are examples of possible warning or caution statements:

(a) Boron:

(i) This fertilizer contains boron which may be injurious to certain crops. Contact your local county agent or field consultant for specific information.

(ii) warning: This fertilizer carries added borax and is intended for use only on alfalfa. Its use on any other crops or under conditions other than those recommended may result in serious injury to the crops.

(b) Molybdenum: caution: This fertilizer is to be used only on crops which respond to molybdenum. Crops high in molybdenum are toxic to grazing animals (ruminants).