FLORISTIC FEATURES OF A PRAIRIE. PROVINCE 



381 



B. Consoeies Sagittaria.. 



Sagittaria latifolia, Polygommi amphihii. 



The ponds of the saucer-shaped region of Grove's Field are 

 practically identical in physical character, varying somewhiat in 

 depth of water, though net exceeding four feet. In some of these 

 ponds, a few species, mostly rare, appear and are not found in 

 other nearby ponds. Only one pond is present in the alluvial 

 basin region. It is of the same type as those in the upland 

 (Groves Field). 



East end of alluvial basin. Iris versicolor. Sagittaria latifolia. 



INVASION, COMPETITION, AND SUCCluSSION. 

 Forest I>'va>siox of Prairie Along Squaw Creek. 



Bordering the nai*row strip of timber along Squaw creek nar- 

 row tributary ravines cut into the morainal deposit ad.iacent to 

 the flood-plain. Bordering- the forest along the flood-plain are 

 colonies of willow and cottonwood just outside the zones of elm 



