At all grade crossings of public highways with railroads outside the corporate limits of any municipality, the highway authority having jurisdiction of such highways shall remove, or cause to be removed from the highway all removable obstructions to view at such grade crossings, such as unauthorized signs and billboards, brush and shrubbery, and shall trim, or cause to be trimmed, all hedges and trees upon the highway for a distance of not less than 300 feet from each side of such crossings.
     No person shall place, or cause to be placed, any sign or signal on a public highway within a distance of 300 feet of any grade crossing, except official traffic control devices authorized in an Act in relation to the regulation of traffic, approved July 9, 1935, as now or hereafter amended, any signs or signals required by law or the Illinois Commerce Commission for the protection of such crossings.
     Any person who violates any of the provisions of this Section shall be guilty of a petty offense and fined not less than $10 nor more than $100 for each offense.