In carrying out the provisions of this chapter, the secretary, or the employees designated by him for the purpose, may:
a. Require the attendance before him, or any of them, of any person from whom reports have been requested, or of any employee of such person;
b. Administer oaths to, and take testimony of, any such person, or his employee; and
c. Require the production by such person, or his employee, of any books, records and other documentary evidence relating to the farm products about which reports have been requested.