(70 ILCS 1835/5.11) (from Ch. 19, par. 705.11)
    Sec. 5.11.
    To restrict the height of any object of natural growth or structure or structures within the vicinity of any airport or within the lines of an approach to any airport and, when necessary, for the reduction in the height of any such existing object or structure, to enter into an agreement for such reduction or to accomplish same by condemnation.
(Source: P.A. 76-1788.)