youth [streams] . The first stage in the hypothetical development of a stream, at which it has just entered upon its work of erosion and is increasing in vigor and efficiency, being able everywhere to erode its channel and having not reached a graded condition. It is characterized by (1) an ability to carry a load greater than the load it is actually carrying; (2) active and rapid downcutting, forming a deep, narrow, V-shaped valley (gorge or canyon) with a steep and irregular gradient and rocky outcrops; (3) numerous waterfalls, rapids, and lakes; (4) a swift current and clear water; (5) a few short, straight tributaries; (6) an absence of floodplains as the stream occupies all or nearly all of the valley floor; and (7) an ungraded bed.