The county commissions of class two counties shall have the power and it is hereby made their duty, upon the petition of a majority of the resident property owners adjoining such road or roads, by order of record, to set aside a strip of land not less than six feet in width, along and from each side of every public road or highway of fifty feet or more in width now or hereafter laid out as a public road, within a distance of two miles of the corporate limits of any city, for the purpose of having planted and cared for shade and ornamental trees and providing for and maintaining footpaths on said strip of land.