88 STUDIES IN THE VEGETATION OF THE STATE 



secure wind dissemination directly by means of rolling pani- 

 cles, pappus modifications, etc. 



The distribution of the facies having been taken up in the 

 structure of the formation needs no further comment here. 

 It should be noted, however, that in the higher prairies the 

 Andropogons form a low, scanty herbaceous covering with 

 only here and there a culm. In the meadows, on the contrary, 

 the forked heads of Andropogon furcatus, the close panicles 

 of Chrysopogon avenaceus, and the bearded spikes of Elymus 

 canadensis* control the aspect. The large, purplish pani- 

 cles of Panicum vi/rgatuin are observed toward the center of 

 draws and in moist parts of meadows. Since these are all 

 tall grasses and generally closely aggregated, there is little 

 to be seen of the few, mostly over-topped,. secondary species; 

 with one exception, Elymus canadensis, these grasses are 

 Footstalk formers and all are pleiocyclic. The Andropogons 

 and Chysopogon enjoy, at least to some extent, dissemination 

 by means of the wind. Spartina cynosuroides is controlling 

 only in parts of the wet meadow where its tall, coarse culms 

 (1^-3 meters) are noticeable on account of their size. The 

 slough grass is perennial with thick, scaly rootstalks. 



Aster multiflorus is present, with two exceptions, in every 

 quadrat from I-XXVII; 275-300 is perhaps a fair average, 

 but not infrequently as many as 2,000 individuals may be 

 enumerated within the five-meter square. The dense, white 

 flowered aster is normally a xerophyte, but it also occurs 

 in low prairies and meadows and with nearly the same abun- 

 dance as in the higher situations; in the latter, however, 

 the patches are usually of greater extent and the individuals 

 more hirsute and reduced in size and leaf surface. As would 

 be expected, the patches are hardly at all noticeable until 

 anthesis, when they give to the floral covering a character- 

 istic white color for almost two months. Aster multiflorus 

 is perennial by rootstalks and also develops small, rather 

 closed rosettes. 



'Elymus canadensis is an estival bloomer refsrred to this place for conTeiiienee. 



