The agricultural commissioner of the county in which any district is situated, may, without fee or charge, supervise and direct, in accordance with the best known accepted methods as determined by the board of directors, all inspection, eradication, fumigation, and other activities undertaken by the district. The agricultural commissioner shall employ any and all assistants required in and about any such work, and the district shall bear and pay all expenses incurred in and about the work. Alternatively, the board of directors may employ a manager to carry out those duties and may employ such personnel as are
necessary.