66 CATALOG OF PLANTS. 



from a few to 30 and, in exceptional cases, 40 feet above the level of 

 Lake Huron. The dunes are mostly very old, and at present the older 

 ones are mostly fixed, being sufficiently covered with grasses, sedges, 

 other small herbaceous plants, shruljs and trees to protect them from 

 the action of wind. (Plate IV b.) A very few small ones near the lake 

 are still forming (Plate II a), but the sand area is not extending farther 

 upon the flat and valuable agricultural land, except where occasionalls' 

 the vegetation is in some w^ay removed from an old and outer dune 

 which is thus exposed to and attacked by the wind. By far the largest 

 dunes in this district are located between Caseville and Port Crescent. 



While the dunes at present are of little value for agriculture and 

 useful only for timber growth and a small amount of pasturage, the land 

 south of them is usually flat, very fertile, and valuable for general 

 farming. In 1909 fine crops of wheat, oats, corn, peas, timothy and 

 clover were noticed, and the farmers appeared thrifty and prosperous. 

 At Sebewaing many large fields of sugar beets were observed and at 

 Bayport a large acreage of onions. The climate and land are also 

 apparently suitable for apples, plums, pears and cherries. 



Between the dunes are bogs, marshes, w^et flats, small tracts known 

 as cranberry marshes, and ponds, some of which are locally called lakes. 

 The largest body of inland water so situated, lying a few miles east 

 of Caseville, is Rush Lake, which is about two miles long by one mile 

 wide, shallow and with a deep muddy bottom. Its surface is about 

 20 feet above the level of Lake Huron. 



" The islands consist of rock, general!}' limestone covered bv a 

 rather thin layer of glacial till that has heen more or less modi- 

 fied by wave and current action while the waters of the bay were 

 subsiding to their present level. The rock is often very thinly covered, 

 as on parts of Stony Island, and low sand ridges are also noticed. They 

 are well covered with trees, shrubs and herbaceous plants, and the 

 vegetation generally is quite primitive. No evidence of cultivation 

 or much pasturage was noticed, except on Stony Island which contains 

 about 800 acres and supported about 45 cattle and a few hogs. Just 

 back of the fishery buildings are fields, formerly cultivated, and an old 

 apple orchard, many of whose trees still bear good fruit. In one part 

 the staghorn sumach has taken possession of the ground and com- 

 pletely overshadowed the fruit trees. The farm buildings, if there 

 ever were any, have disappeared, except an old log stable. North 

 Island has an area of about 86 acres. Charity Island, owned by the 

 U. S. Government and used for lighthouse purposes, contains over 640 

 acres; Little Charity Island, a fraction over 4 acres. In 1909 the fishery 

 buildings on the islands were not occupied except on Little Charity 

 Island. 



