The regulation, planting, care and control of shade and ornamental trees and shrubbery upon or in the highways (except county highways), parks or parkways of the borough shall be exercised and be under the authority of the Shade Tree Commission. The commission, to be known as the "Shade Tree Commission of the Borough of Rumson," shall consist of no fewer than five (5) members no more than seven (7) members appointed by the Mayor and shall serve without compensation.