Erosional problems and damages include loss of land, imperilment 

 to roadways, loss of recreational beach, loss of access to the lakes, 

 and structural damage to dwellings, boathouses, docks, and stairways. 

 Some shoreline conditions along the Great Lakes are difficult to alter 

 to control erosion, particularly in areas where there is no beach or 

 where the water interfaces immediately with steep bluffs. However, 

 there are numerous areas where erosion can be abated by attenuating 

 wave action with mechanical barriers and then using terrestrial and 

 aquatic vegetation to protect the shore against the reduced wave action 

 and against surface runoff. 



There are three types of terrestrial plants that can be used to 

 abate erosion: (a) pioneer plants, the species to first become 

 established on new substrates; (b) secondary plants, the species to 

 first invade edaphically stable areas colonized by the pioneer plants; 

 and (c) tertiary plants, the species poorly adapted to dynamic conditions 

 and requiring areas previously stabilized by pioneer and secondary 

 species . 



Most species used in terrestrial planting operations are the pio- 

 neer type. The pioneer initiates a development sequence (Cowles, 1899; 

 Hack, 1941). It stabilizes the surface, provides lodging for windborne 

 disseminules, shields seedlings from sun and wind, and prepares the way 

 for natural invasion of other plant types (Daubenmire, 1968) . 



Establishment of hydrophytes (submergent or emergent plants) is 

 very difficult. They are highly restricted by currents and water level 

 fluctuations. Emergent hydrophytes are limited to low-energy shores, 

 where they modify less forceful waves; submergent aquatic plants estab- 

 lish in even more protected areas . The restriction of submergent 

 species to quiet waters limits their phytogeographical distribution, 

 and their vulnerability to strong wave forces prohibits them from natu- 

 rally colonizing the wave-swept littoral zones of lakes. 



The main purpose of this investigation was to determine if terres- 

 trial and hydrophytic plants, either alone or in combination with 

 structures, can be used to attenuate wave energy immediately offshore 

 and to stabilize the areas adjacent to the waterline, thereby reducing 

 the erosion rate along the Great Lakes shores. 



II. PROCEDURES 



The study was conducted in two phases, a literature search and a 

 field survey. In both parts of the study, the emphasis was on vegeta- 

 tion endemic to the Great Lakes area, because these plants are expected 

 to be well adapted to the present environmental, edaphic, and climato- 

 logical stresses. 



1. Literature Search . 



The literature was reviewed for pertinent information on plants 



