A stake consists of two planar panels joined on a longitudinal axis and angularly disposed with respect to one another. Lower portions of the panels converge to a tip on the axis, and an axial tang is formed at the top of the stake. An inwardly directed flange is formed near the top of each panel, the flanges being disposed substantially in a common plane, generally perpendicular to the panels. The flanges and the tang facilitate driving of the stake into a substrate by use of a power hammer, and the driven stake resists both upward and lateral displacement. It is especially adapted for the securement of edging for restraining paving and landscaping materials.