CONTENTS 



PAGE 



Introduction 255 



Location and Physiography 256 



Physiographical History 257 



Climate 259 



Edaphic Factors 259 



Influence of Lake Michigan 260 



General Description of the Area 261 



Associations : General Consideration 262 



The Lower and Middle Beach Associations 266 



The Chlaniydomonas Association 266 



The Cakile-Xanthium Association 269 



The Middle Beach Pool Associations 273 



The Juncus alpinus insignis Association 27s 



The Triglochin palustris Association 274 



The Carex ocderi pumila-Cyperus rivularis Association 274 



The Sabatia-Linum Association 275 



The Juncus balticus liitoralis Association 276 



The Potentilla anserina Association 278 



The Dune Formation 280 



The Dune Associations 282 



The Calamovilfa longifolia Dune Association 282 



The Ammophila arcnaria Dune Association 283 



The Salix syrticola Dune Association 285 



The Prunus pumila Dune Association 286 



The Populus candicans Dune Association 287 



The Elyrnus canadensis Dune Association 287 



The Juniperus Dunes Association 288 



Miscellaneous Dunes 289 



The Populus-Salix Dune Association 289 



The Salix glaucophylla Dune Association 290 



The Panicum virgatnm Dune Association 290 



The Andropogon scoparius Dune Association 291 



The Populus-Salix-Cornus Thicket Dune Association 291 



The Betula alba papyrifera Dune Association 291 



The Relic Dune 292 



The Man-made Dune 292 



The Traveling Dune 293 



The Upper Beach Associations : 



The Artemisia-Panicum Association 293 



