80 STUDIES IN THE VEGETATION OF THE STATE 



in meadows and swamps. Its clusters of white flowers ap- 

 pear about June 1 and continue for forty days. The Indian 

 hemp is a perennial with deep, thick roots, from which propa- 

 gation results; hence its tendency to form clumps. Dry, 

 grassy banks of streams are the favored haunts of A. cannabi- 

 num. Dissemination is as for the milkweeds. Physalis longi- 

 folia is a tall, bushy perennial inhabiting mostly the Carex 

 facies of the wet meadow. It averages four to ten individu- 

 als per quadrat. 



The remaining plants of the early estival floral aspect are of 

 importance principally because of their presence. They 

 neither add to the aspect nor the floral covering. With per- 

 haps one exception, Physalis heterophylla, which occurs 

 rarely throughout the prairie, all are ruderal or adventitious 

 species. Agrostis alba, Phleum pratense, and Poa pratensis 

 form a zone a few meters in width on the west of the wet 

 meadow. Plantago major and P- rugellii occur in the drier 

 parts of the wet meadow. They are perennial plants with 

 short, thick rootstalks, forming open rosettes which "freeze 

 out" during the winter. The flowers of these plantains are 

 aianthous, anemophilous, proterogynous, and xenogamous. 

 The long, exserted stamens appear several days after the 

 stigmas. Potentilla monspeliensis is a dicyclic herb growing 

 below the tall, wet meadow facies. It forms open rosettes, 

 the inner leaves of which are protected with the broad stip- 

 ules and bases of the outer ones. 



During excessive precipitation, soil from neighboring cul- 

 ture formations is transported to parts of the sedge meadow. 

 These deposits are soon covered over with a dense growth 

 consisting of such ruderals as Solanum caroUnense, Lactuca 

 pulchella, Chaetochloa viridis, C. glauca, Ghcnopodium al- 

 bum, Amaranthus graecizans, and Convolvulus sepium. The 

 common tumbling weed, Amaranthus graecisans, and also 

 the following spurges. Euphorbia glyptosperma, E. nutans, 

 and E. maculata, grow abundantly on the mounds in the 



