Dirt, and where it comes from

We farm in a very special place. The lower Snoqualmie river valley is a small but highly fertile floodplain, just a half hour away from the big city of Seattle. It has been farmed continuously since the early 1900s, transitioning from homesteads to family-run dairies to the amazing diversity of crops that are grown here today: mixed vegetables, intensive flower fields, beef, laying hens, berries, and hay for dairy cows. It is also home to a wonderful community of farmers and friends of farmers. One of the mainstays of our farming community is Sno-Valley Tilth. We meet every month for a potluck and meeting, sometimes to share information with each other and sometimes to hear a guest speaker. Last night’s potluck took place here on our farm, and featured UW professor and author David Montgomery.

Dr. Montgomery is a geomorphologist, and he has written a great book, “Dirt, the Erosion of Civilizations,” about how agricultural soils are formed by nature and (usually) destroyed by man’s farming practices. I read his book many years ago, when we first started farming here, and was delighted to get to hear him speak in person. “Dirt” describes how floodplains, like ours, are the only places where civilizations have been able to sustain agriculture over the long run. The seasonal flooding we experience is, in fact, regenerative. The river brings silt and sand down from the mountains, and the floods stir it up from the river bottom and deposit it on our fields. Everywhere else on earth has soils that, when disturbed, erode and flow downstream. Soils, in naturally vegetated state, will grow at a rate of 1/100th of a millimeter a year. Once plowed, it can erode at a millimeter a year or more.

Soil is an under-appreciated and precious resource and we are in the lucky possession of 80 acres of the best soil in the world. We take the stewardship of this resource very seriously! All of our farming practices revolve around a consideration of the long-term impacts of the soil, trying to carefully balance this with the short-term need for economic viability. I highly recommend “Dirt,” as a primer on the fascinating interrelationship between geologic forces and human civilization.