St. Joseph Island is a fascinating borderland where the hard rock of the Canadian Shield is overlain by younger sedimentary rock, Paleozoic limestone. The ancient Shield surfaces at the northeast corner of the island, with steep rocky ledges dropping abruptly into the St. Marys River. Except for the occasional surface intrusion by Shield rocks, the remainder of the island is made up of Ordovician and, along the southern tip, Silurian limestone—approximately 450 million years old. St. Joseph Island is sometimes referred to as the “tail” of the Niagara Escarpment, since it is the northwestern extension of that famous limestone ridge.

The Ojibwa described the island as niibiish or “leafy”, because of the abundant deciduous trees, particularly maple and beech. The soils on St. Joseph Island are a mixture of fertile clays and less fertile sandy material deposited largely from the Shield. Nevertheless, the area is often referred to as the Garden of the Algoma. The waters around the island support a wide range of fish species, but not in the seasonal concentrations of whitefish that made St. Marys River rapids more desirable to the Ojibwa.

In order to station troops on St. Joseph Island, or Payentanassin, King George III of England purchased the land from the Ojibwa Nations on June 30, 1798. The price? Goods valued at 1200 pounds, Quebec currency; including 680 pairs of blankets of various weights, 260 yards of embossed serge, guns, kettles, 24 gross of pipes, 300 pounds of tobacco, 15 dozen looking glasses, 50 gallons of rum, a bullock and much more.

Keep alert for white-tailed deer. The St. Joseph Island population is usually high and car/deer collisions are not uncommon.

As you move away from St. Joseph Island and along the North Channel of Lake Huron between Desbarats and Blind River, you return once more to the Southern Province of the Canadian Shield. Here, you will find telltale evidence of the resources that attracted settlers following the fur trade: agriculture, mining, forestry and fishing. Deposits of clay soils between Bruce Mines and Blind River drew early farmers, but unlike the prairie soils of the Western Plains, these deposits are patchy and the climate is marginal for agriculture. The forest is still primarily hardwood, reflecting the moderating influence of Lake Huron. Pine forests just to the north once supplied the massive North Channel and Georgian Bay lumber industry. Woodland caribou ranged this far south, but with the destruction of their habitat, their niche has long since been filled by deer and moose.

Commercial fishing used to be extensive along the North Channel, but was virtually destroyed by overfishing and by the lamprey invasion. Today the fishery, although small by historical comparison, remains an important part of the economic activity in Thessalon, Blind River and other towns.