Nov., 1910.] .4 Floristic Survey of Orchard Island. 



207 



The two bordering formations the marsh-herb on the one side 

 and the forest on the other, merge in the areas between the shrub 

 societies. The presence of seedling Ulmus, Quercus and 

 Gleditsia, in the Hibiscus-Typha society shows clearly that 

 the forest is invading the marsh, and if the higher portion of the 

 mud flat is not again submerged, the shrub zone ma}^ never 

 become more complete than it is now; it may be formed farther 

 down on the shore or it may be entirely replaced by the forest. 

 The incompleteness of the shrub zone is due to the existence of 

 the forest prior to the development of the marsh. 



III. Mesophy tic-forest formation. 

 7. Ulmus-Fraxinus society. 

 Facies. 



Ulmus americana. 



Secondary species. 

 Trees. 



Fraxinus nigra. 

 Hicoria ovata. 

 Hicoria minima. 

 Ulmus fulva. 

 Quercus palustris. 



Lianas. 



Rhus toxicodendron. 

 Vitis vulpina. 

 Parthenocissus quinquefolia. 



Shrubs. 



Cornus stolonifera. 

 Rubus nigrobaccus. 

 Rubus occidentalis. 



Herbs. 



Muhlenbergia diffusa. 

 Agrostis perennans. 

 Syntherisma sanguinalis. 

 Syntherisma linearis. 

 Chaetochloa glauca. 

 Carex tribuloides. 

 Carex vulpinoidea. 

 Carex frankii. 

 Rynchospora alba. 

 Solidago canadensis. 

 Aster paniculatus. 

 Aster sagittatum. 

 Nepeta cataria. 

 Teucrium canadense. 

 Carduus lanceolatus. 

 Arctium minus. 

 Helianthus decapetalus. 



Fungi. 



Agaricus campestris. 



Fraxinus americana. 



Celtis occidentalis. 

 Tilia americana. 

 Gleditsia triacanthos. 

 Morus rubra. 

 Salix nigra. 



Smilax hispida. 

 Solanum dulcamara. 

 Dioscorea villosa. 



Rosa Carolina. 

 Cephalanthus occidentalis. 



Urtica gracillima. 

 Erigeron canadensis. 

 Hedeoma puligioides. 

 Mentha canadensis. 

 Lycopus americanus. 

 Oxalis stricta. 

 Onagra biennis. 

 Solanum nigrum. 

 Epilobium strictum. 

 Verbena urticifolia. 

 Rumex obtusa. 

 Geum canadense. 

 Meibomia viridifiora. 

 Eupatorium ageratoides. 

 Eupatorium purpureum. 

 Bidens bipinnata. 



Lycoperdon wrightii. 



