30 



The Botanical Survey of Nebraska 



killing back many of the shrubs, especially RJnis glabra which 

 was encroaching upon the grassland from the shelter of the more 

 moist ravines and protected slopes. The dominance of Andro- 

 pogon scoparius and the general structure of the prairie vegeta- 

 tion is shown in the following list quadrats carefully selected near 

 the station and listed in September. It is clear that at this time 

 certain prevernal and vernal blooming species had disappeared. 



Species 



Andropogon scoparius 



individuals 



bunches 



Andropogon furcatus 



individuals 



bunches 



Bouteloua curtipendula .... 



individuals 



bunches ■ 



Eragrostis pectinacea 



individuals 



bunches 



Sorghastrum avenaceum 



individuals. 



bunches 



Amorpha canescens 



Brauneria pallida 



Ceanothus ovahis puhescens . 



Euphorbia corollata 



Kuhnia eupatorioides 



Lygodesmia jiincea 



Lespedeza capitata 



Liatris punctata 



Petalosleinon purpurea 



Rosa arkansana 



Ulmus americana (seedling) 



Remarks 



Bunches t to 6 inches in diam. 



Bunches 2 to 4 inches in diam. 



Bunches from 2 to 6 inches in 

 diam. 



Bunches from i to 4 inches in 

 diam. 



Bunches only i to 2 inches in 

 diam. 



The shrub station is dominated by Corylus americana and RJnts 

 glabra. These with Symphoricarpos symphoricarpos, small trees 

 of Cercis canadensis and Primus americana form rather dense 

 thickets from 5 to 8 feet in height. Several woody lianas such 

 as Celastrus scandens, Vitis vulpina, and Ampelopsis qiiinque- 

 folia are present in sufficient numbers to add considerably to the 

 mass of vegetation. The following list, tabulated in September, 

 shows the variety and abundance of species of shrubs, small 



36 



