MacMillan: shores at lake of the woods. 1013 



Thus the boulder shore is developed excellently on the side of 

 Big island facing Garden island, quite open to the winds and 

 waves of the Grand Traverse. This difference in exposure 

 gives to a boulder shore more the character of strand, but, 

 because of the irregular surface, strand zonal distribution does 

 not readily arise, although there is commonly formed a group 

 of plants back on the shore somewhat analogous to back-strand. 

 According to contour two types of boulder shore may be dis- 

 tinguished, the flat or boulder strand, and the rounded or boulder 

 slope. If the boulders are large the conditions are not the 

 same as if they were small. 



Coarse boulder shores. Such a name may be applied to 

 those shores where boulders a foot or more in diameter are 

 bedded in sand or soil. That they should be bedded in soil is 

 possible only in sheltered coves or behind surf barriers. Ord- 

 inarily they are bedded in sand. 



I. Boulder strand. This name may be applied to low-lying 

 beaches which are covered with half-buried boulders of large 

 size. The boulders themselves support a lichen population 

 with occasional growths of moss or even of ferns, but the latter 

 condition is rare. The intermixed sand bears ordinary psam- 

 mophytic plants and the combination presents much the 

 aspect of talus and sand as described above. A difference, 

 however, lies in the greater exposure of such a shore, so that 

 the lichens are scanty, dwarfed and not of the Cladonia types, 

 but rather Endocarpons. Amid these lichen- groups an algal 

 flora may flourish in boulder-strand-pools, the boulders them- 

 selves, by their interference with the regular wash of surf, 

 favoring the development of strand pools. And neighboring 

 closely upon the po<fl-flora and the lichens willbe the Ambrosia, 

 Epilobium, Onagra and Elymus vegetation of typical beach. 

 The boulders offer shade and shelter, to some extent, so the 

 strand herbs become distributed with reference to them rather 

 than to the general shore line, as in ordinary strand. Coarse 

 boulder strand is, then, to be regarded as an azonal modifica- 

 tion of ordinary strand. 



II. Boulder slopes. Like talus slopes, these may have a 

 greater or a less percentage of enclosed humus and the char- 

 acter of the vegetation varies with the percentage. Usually, 

 however, unless recent denudation has been in progress, the 

 shores are strongly nitrogenous and separate into two areas, 

 upon analysis. The region nearer the water's edge differs 

 from that farther back and maintains a plant population of a 



