50 



Trees 



Abies balsainea Populus bahamijera 



Acer pennsylvanicum Populus grandidentata 



Acer rubrum Populus tremuloides 



Acer saccharum Prunus pennsylvanica 



Betula papyrijera Prunus mrginiana 



Fagus grandijolia Thuja occidentalis 



Fraxinus nigra Tsuga canadensis 



Pinus strobus Ulmus americana 



Summary 



1. The effect of inundation upon upland vegetation (beech- 

 maple forest and lowland forest) was studied above a beaver dam 

 in Carp Creek (an area of approximately 9700 square meters), 

 in the vicinity of Douglas Lake, Michigan, during the second 

 summer of its construction. 



2. The original vegetation was affected seriously. All herbace- 

 ous vegetation with two exceptions was eliminated following the 

 flooding; no shrubs except seedlings or very small saplings, on 

 large logs at or in the water, were to be found, and 77% of all 

 the trees in the empounded area were dead or dying. 



Kansas State Agricultural College 

 Manhattan, Kansas. 



Explanation of plate 



A. The west end of the dam contrasting the unattacked area In the background 



with that worked over in the foreground. 



B. Upstream over the dam. The large hemlock near the left is now in 1.3 meters 



of water. 



C. Appearance towards the upper end of the pond. 



Photographs A by F. C. Gates; B by H. K. Gloyd; and C by Edward Breakey. 



AN ECONOMICAL HERBARIUM CASE 



E. D. Merrill 



I was recently obliged to provide storage space for a large 

 and rapidly increasing herbarium, in connection with my efforts 

 to build up at the University of California a general Indo- 

 Malaysian and Chinese reference collection. Within a period 

 of less than two years material in excess of 40,000 mounted 



