From the book, The Forests of Michigan, describing the timber industry in Michigan from about 1880 to 1920:
The final lumber tally from the Michigan timber boom is staggering: approximately 161 billion board feet of pine (50 percent more than that produced in Wisconsin and Minnesota combined) plus 50 billion board feet of cedar, hemlock, and hardwoods. … The value of lumber output from Michigan’s pineries exceeded by a billion dollars the gold extracted in the 60 years that followed the rush to California in 1849 (Wells 1978).
After the boom, virtually nothing remained of that vast Michigan pinery whose end was believed by many to be unreachable.
When the forests were depleted, the lumber barons packed up and left with their fortunes.