a channel or miniature valley cut by concentrated runoff, through which water commonly flows only during and immediately after heavy rains or during the melting of snow —note 1. gullies may be branching or linear, long, narrow, and of uniform width —note 2. the distinction between gully and rill is one of depth: a gully is sufficiently deep that it would not be obliterated by normal tillage operations; a rill is of lesser depth and would be smoothed by ordinary farm tillage This definition last updated 10/27/2008