77 



Plate 30.— Classification: SYSTEM Lacustrine, subsystem Littoral, class Emergent Wetland, SUBSYSTEM Nonpersistent, water 

 REGIME Permanently Flooded, WATER chemistry Fresh, SOIL Unknown. The dominant plant is pickerelweed [Pontederia 

 cordata). (Washington County, Maine; June 1978; Photo courtesy of P. B. Reed) 



