The county planning commission shall be composed of seven (7) members to be appointed by the board of county commissioners. One member shall be a member of the board of county commissioners and the remaining six members shall be residents of the unincorporated areas of the county. The term of the county commissioner member shall be coextensive with his term of official office, and all other members shall be appointed for terms of six (6) years, except that such terms shall be made overlapping and the respective terms of those first appointed may be less than six (6) years. All members shall serve as such without compensation. Members may be removed by the board of county commissioners for cause after a public hearing held for that purpose and vacancies shall be filled by additional appointments.