FLORISTIC FEATURES OF A PRAIRIE PROVINCE 3 77 



vicinity though in the lowland ruderals well adapted to the moist 

 halbitat usually completely supplant the original flora. 



A nearby plum-elm thicket in an unmowed ravine on the other 

 side of this hill has caused the grass to disappear from the earth 

 and it is replaced by grove plants. Here is a tendency toward 

 preliminairy forest formations. 

 II Meadow or Wet Prairie. 

 Panicum-Agrostis Formation. 



Location: Between highland and marshes, extends up ra- 

 vines bordering streams. 

 Soils : Alluvial, sandy to clay loaim. 



Fig. 152. — Pond in alluvial basin. 



Arrangement : Copious, gregarious-copious. 



The more important species are : 

 Andropogon provincialis, Sorgasirmn nutans, Panicjiyn Scnhne- 

 rianum., Panicum virgatum, Agrostis alha, MuhJenbergia race- 

 mosa, Spartina cynosuroides, Sium cicutaefoUum, Ciciita ma- 

 cidata, Gerardia aspera, Gerardia tenuifoUa, Petalo sternum 

 pnrpureum, Petalo sternum candiduyn, Fragaria virginiana var. 

 illinoense, Erigeron annuus, Rosa pratincola, Senecio aureus, 

 Thalictrwm dasycarpum, Anemone canadensis, Phlox m^acidata, 

 Pedicidaris canadensis, Pedicidaris lanceolate, Lythrum ala- 

 turn,, Habenaria leucophaea, Steironema ciliatum, Steiro- 

 nema lanceolatum; Steironema quadrifoUum, Lippia lanceo- 



