Rudbeckia laciniata L., wild goldenglow. 

 Helianthus tuber osus L., Jerusalem artichoke. 

 Cacalia atriplicifolia L., Indian plantain. 



VIII. THE LAKE CLIFF ASSOCIATIONS 



The shore of Lake Michigan, north of Chicago, exhibits a series of 

 high clay cliffs cut in the moraine. These differ in slope according to the 

 character of the soil and in their vegetation according to whether or not 

 they are being attacked by waves at the present time. The earliest 

 plant associations consist of the antecedent vegetation which has slumped 

 from the upland together with shrubs and perennial herbs with means 

 of rapid vegetative propagation which enable them to compete with 

 the unstable substratum. Only the plants peculiar to the pioneer 

 stages of the succession are included in the following list, as those of the 

 beach and the mixed oak forest differ very little from corresponding 

 associations upon the sand dunes {q.v.). The ravines opening upon the 

 shore have the vegetation of the lake cHffs upon their exposed slopes 

 and that of the mesophytic forest {q.v.) and flood plain {q.v.) upon the 

 more protected areas. 



Trees and Shrubs 

 Pinus Strobus L., white pine. 

 Juniperus virginiana L., red cedar. 



" communis L., common juniper. 

 Thuja occidentalis L., arbor vitae. 

 Salix discolor Muhl., pussy-willow. 



" glaucophylla Bebb, glaucous willow. / 



Populus tremuloides Michx., aspen. 



" grandidentata Michx., large-toothed aspen. 

 " balsamifera L., balsam poplar. 

 Corylus americana Walt., hazelnut. 

 Ostrya virginiana (Mill) K. Koch., hop-hornbeam. 

 Car pinus caroliniana Walt., ironwood. 

 Betula alba papyrifera Spach., white birch. 

 Amelanchier canadensis (L.) Medic, service-berry. 

 Rosa blanda Ait., wild rose. 



" humilis Marsh., wild rose. 

 Prunus virginiana L., chokecherry. 

 Acer Negundo L., box-elder. 

 Rhus typhina L., staghorn sumach. 



" glabra L., smooth sumach. 



" Toxicodendron L., poison-ivy. 

 Ceanothus americana L., New Jersey tea. 

 Shepherdia canadensis (L.) Nutt., buffalo-berry. 

 Elaeagnus argentea Pursh, silverberry. 

 Tilia americana L., basswood. 



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