In all counties of this State containing a city having more than seventy thousand population, according to the then most recent United States official census, there is hereby levied and imposed an annual license fee upon all motor vehicle junk yards which are located within fifty feet of the right of way of any state highway or county road or which shall be visible from any such highway or road, such license to be graduated according to the area occupied by each such motor vehicle junk yard at the rate of one hundred and fifty dollars per acre. Such license fee shall be due and payable on or before July first of each year.