A.
On a corner lot in all zoning districts, no fence, wall, hedge, planting or structure shall be erected, placed, planted or allowed to grow in such a manner as to obstruct vision between a height of 2 1/2 feet and 10 feet above the center-line grades of the intersecting streets in the area bounded by the street lines of such corner lots and a line joining the points along said street lines 25 feet from the point of intersection.
B.
In the case of arterial streets intersecting with other arterial streets or railways, the corner cutoff distances establishing the triangular vision clearance space shall be increased to 50 feet.