Environmental Description:  Sites encompass the bottoms and toeslope terraces of small, high-order, more-or-less high-gradient mountain streams at elevations less than 760 m (2500 feet). Hydrologic regime is probably similar to that reported for Passage and Mill creeks in the Massanutten Mountains, where annual water table fluctuations are dramatic and small-scale fluvial landforms greatly influence species distributions (Hupp 1982, 1986, Olson and Hupp 1986). The lowest terraces of these narrow bottoms are probably flooded briefly once a year, while higher terraces are inundated only during rare, catastrophic floods. Slope ranges from 0-10° and aspect is variable. Microtopography is complex and includes floodplains, terraces, fans at tributary hollow mouths, and various bank features. Coarse woody debris, boulders, and cobbles transported by flood events are usually prominent components of the surface substrate. Soils are highly variable and range from well-drained to poorly drained. Soils collected from plot-sampled stands were strongly acidic (mean pH = 5.2) with moderately low base status.