On a corner lot in any residential district, nothing shall be erected, placed, planted, or allowed to grow in such a manner as materially to impede vision between a height of two and a half and ten feet above the centerline grades of the intersecting streets in the area bounded by the lot lines of such corner lots and a line joining points along said lot lines 15 feet from the point of the intersection of the lot lines.
(Prior Code, Art. 21, § 21-109.1)