298 MINNESOTA BOTANICAL STUDIES 



rush-sedge wet meadow association, or, in the absence of this, 

 where it meets the marsh formation. 



The usual position of the association in relation to other vege- 

 tation groups has been indicated as between the xerophilous upland 

 associations and some one of the lowland associations already 

 described. Toward the uplands the hay meadow very soon fuses 

 with, and is lost in, one of the typical grass associations of the hills, 

 most commonly the bunch-grass association. In the opposite direc- 

 tion the hay meadows may give way at once or through a less con- 

 spicuous transitional belt to either rush-sedge wet meadow associa- 

 tion or to some aspect of the marsh formation. 



Naturally many of the typical meadow grasses are to be found 

 here, and with them numerous herbaceous associates of meadow 

 associations farther eastward as well as some of those species more 

 or less common in the outer stretches of the above meadow associa- 

 tions, as they occur within our sandhills. This association is some- 

 what like the "long-stemmed" grass formation of Pound and Clem- 

 ents. It includes the most of Rydberg's (58) "dry valley" and 

 "meadow" species. 



Composition of the Hay Meadow Association 



DOMINANT species 



Agropyron pseudorepens Elymns canadensis 



Agropyron smithii Koeleria cristata 



Agropyron tenerum Panicum virgatitm 



Agropyron violaceum Spartina cynosiiroides 



Agrostis alba Stipa comata 



Andropogon furcatus Stipa spartea 

 Calamagrostis neglecta 



associated species of VARYING RANK 



Amorpha canescens Drymocallis arguta 



Andropogon scoparius Eatonia ohtiisata 



Anemone cylindrica Equisetnm laevigatum 



Beckmannia erucaeformis Equisetum pratense 



Boltonia asteroides Erigeron bellidiastrum 



Bonteloua cnrtipendula'- Euthamia graminifolia 



Calamovilfa I on gi folia Fragaria virginiana 



Ciciita occidentalism Helianthus subrhomboideiis^ 



Delphinium albescens Lacinaria spicata 



