Not less than 75 percent of the directors of a bank shall, during their whole term of service, be citizens of the United States. Every director of a bank shall be the owner and holder of shares of stock in the bank or parent bank holding company. Every director shall hold such shares in his or her own name, unpledged and unencumbered in any way except statutory lien which might attach in favor of such corporation. No person convicted of a felony or a crime involving moral turpitude shall serve as a director. At least 51 percent of the directors of every bank shall be residents of the state. Any director at any time violating any of the provisions of this section shall be removed from office by the board of directors or by the superintendent when the facts are made known to the superintendent.