(a) For the purpose of selecting committee members, the following districts of the production area are hereby initially established:
District No. 1 (Emmett, Payette, Weiser Area): All territory within the boundaries of Washington, Payette and Gem Counties, in Idaho.
District No. 2 (Oregon Slope): All territory within a boundary following the Snake River northwesterly from its junction with the Malheur River, to the west line of Range 46E; thence south along said west line to the south line of Township 17S, and thence east along said south line to its junction with the Malheur River, and thence northeasterly along the Malheur River to the junction with the Snake River, the point of beginning.
District No. 3 (Ontario, Vale, Jamieson, Brogan): All territory within a boundary starting at the junction of the Malheur River with the Snake River and extending southwestward along the Malheur River to its junction with the south line of Township 17S, E. W. M.; thence westward along this line to its junction with the west line of Range 46E; thence north along this line to its junction with the Snake River; thence northwest along the Snake River to its junction with the north boundary of Malheur County; thence west along the north boundary of Malheur County to the west boundary of the county; thence south along the west boundary of Malheur County to its intersection with the south line of Township 20S; thence east along this line to its junction with the Hyline Canal and Siphon; thence northeast along the Hyline Canal to its intersection with Highway 20; thence east along Highway 20 to Cairo Junction; thence south 1⁄8 mile to the junction of Highway 20 to Oregon Avenue; thence east along Oregon Avenue to its termination at the Snake River; thence north along the Snake River to its junction with the Malheur River, the point of beginning.
District No. 4 (Nyssa-Adrian): All the area of Malheur County, Oregon, south of District No. 3.
District No. 5 (Parma, Wilder, Nampa, and Notus Area): Canyon County, Idaho.
District No. 6 (Homedale, Marsing, Meredian, Melba, Mountain Home, Glenns Ferry and Twin Falls Area): All counties in the Idaho portion of the production area not included within Districts Nos. 1 and 5.
(b) The Secretary, upon the recommendation of the committee, may reestablish districts within the production area and may reapportion committee membership among the various districts: Provided, That in recommending any such changes in districts or representation, the committee shall give consideration to: (1) The relative importance of new producing sections; (2) changes in the relative position of existing districts with respect to onion production; (3) the geographic location of areas of production as they would affect the efficiency of administering this part; (4) other relevant factors: Provided, further, That there shall be no change in the total number of committee members or in the total number of districts.