^ 



edge. This gradual sloping may have resulted from frequent inundation and 

 deposition of sandy alluvial soil. 



The meadow is bounded on the west and east by forests of Pseudotsuga 

 menziesii and Pinus ponderosa . The northern edge, at the base of a steep, 

 rocky slope, is fringed by Betula and Alnus . Clumps of Betula , Alnus , and 

 isolated Pinus ponderosa occur in the western third of the meadow. A grassy 

 community with clumps of heavily-browsed Amelanchier alnifolia and other 

 shrubs forms a band across the northern third of the meadow. Much of the 

 remainder of the meadow is dominated by Agropyron repens and Poa pratensis . 

 Transect No. 1 was placed in this latter community type (see table 7). 

 Transect No. 2 sampled a community type dominated by Plantago lanceolata and 

 Poa pratensis . Although not included in the transect, clumps of Agrostis 

 alba are present in this community. Transect No. 3 was placed in a community 

 type dominated by Filago arvensis and Bromus tectorum . Over 60% of this 

 community type consists of bare ground, indicative of the poor water-holding 

 capacity of the sandy soil. Young Populus trichocarpa seedlings are invading 

 the meadow near its western and eastern edges. A fringe of scattered Populus 

 trichocarpa and Pinus ponderosa delineates the southern edge of the meadow. 



Upstream Meadow . This meadow (see figure 8) lies 11,300-12,800 feet 

 upstream from the falls. It is about 480 m long, and has a maximum width of 

 30 m. Elevations range from about 2,006 to 2,012 feet (msl). A small stream 

 lined with Populus trichocarpa , Acer glabrum , Betula , and Alnus incana 

 divides the meadow into halves. The northern edge of the meadow, which abuts 

 a steep rock cliff, is lined with Betula , Alnus incana , and Acer glabrum . 

 Tanacetum vulgare , Melilotus alba, and Centaurea maculosa dominate the bank 



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