(a) General.--Except as provided in subsection (b), a shade tree commission shall be composed of three residents of the borough who shall be appointed by the council and shall serve without compensation.

(b) Council option.--The council, by ordinance, may provide that a shade tree commission be composed of five members who shall be residents of the borough, shall be appointed by the council and shall serve without compensation.

(c) Three-member commission.--If a shade tree commission of three members is established by any borough, the council shall appoint one member for a term of three years, one for a term of four years and one for a term of five years. On the expiration of the term of any commissioner, a successor shall be appointed by the council to serve for a term of five years.

(d) Five-member commission.--If a shade tree commission of five members is established by any borough, the council shall appoint members to staggered terms so that one term expires every year. On the expiration of the term of any commissioner, a successor shall be appointed by the council to serve for a term of five years.

(e) Vacancies.--Vacancies in the office of commissioner shall be filled by the council for the unexpired term.