1491 - America Before Columbus

Last week we had several history lessons, we are transitioning from the history of several world changing plants to considering how several civilizations "bio-engineered" their soils. Charles Mann in his book 1491 talks about what America was like before Columbus. It is a very interesting read and has much food for thought. He says the Native American populations were vast. To feed their civilization they were able to grow massive crops through highly advanced agriculture.

At the same time that the North American Natives were building their civilization with temperate soils the cultures of the central Amazon were building their civilization in rain forest soils with extremely low fertility. Thousands of years later the soils they engineered are some of the most fertile in the world. These soils are so persistent that they actually grow back when the top layer is removed.

Both civilizations sustained hundreds of thousands, perhaps millions with their ancient growing techniques. I think there is a lot to learn from what they did.

So how does this apply to Market Gardening in Minnesota?


The common thread in the fertility of both cultures is pyrolized carbon, which is commonly known as charcoal.

The Amazons mixed biochar with their compost piles and then used this mix over thousands of years to create Terra Preta or Black Soil. This soil created by these ancient civilizations persists a thousand years later.

The temperate soils of North America also contain up to 3% charcoal from the burning of the prairie. This is one reason that the deep prairie soils of Illinois, Southern Minnesota and Iowa are so fertile.

We are starting a series of posts on biochar. Making charcoal from waste wood on the farm and using it to enrich our soils.

Reed and I have been experimenting with how to make it and have been successful on a limited basis.