Harvest Time On the Prairie - Thin Brown Line is Getting Thinner


I ventured up to Peone Prarie last week to take some pictures andthey just happened to be harvesting the wheat. The dust was flying and I couldn’t help but think about the book I’m reading titled, “Dirt: The Erosion of Civilizations” by David Montgomery. In the book he looks at history through the lens of soil fertility, erosion and depletion concluding that the rise and fall of civilizations can often be traced to the exploitation and depletion of soils.

It is a fascinating read and I highly recommend it. Soil, or the thin brown line as Montgomery calls it, is much more complex than I thought. One example from the book describes a WSU study done in the mid ‘80’s comparing two dry land wheat farms near Spokane. Both farms were first plowed in 1908, one never using commercial fertilizers and the other using commercial fertilizers since 1948. Both farms boasted the same income, one leaving the field fallow every third year for a cover crop and the other harvesting continuously but paying big bucks for fertilizers and pesticides. They harvested more wheat but had much higher expenses that canceled out any economic advantage. Most importantly the researchers found that the organic farm was building soil while the conventional farm had shed 6 inches of topsoil between 1948 and 1985.

Montgomery sums up the study by saying, “With fifty more years of conventional farming, the region’s topsoil will be gone. Harvests from the region are projected to drop by half once topsoil erosion leaves conventional farmers plowing the clayey subsoil.” I’m assuming that the whitish soil I see peaking through at the top of the rolling ridges of freshly plowed palouse is the clayey subsoil peaking through.

Yikes! More on this later.