Signs of Soil Loss

Inside Dakota Ag

Snirt snowdrifts and mountains of silt are signs that soil erosion is real and the losses can really add up over time.

Published on: March 27, 2013

There were a couple times this winter when it was pretty easy to see soil erosion happening.

During a couple blizzards, the air was filled with blowing snow and dirt -- snirt, as it's called in the Dakotas. On a trip I made from my farmstead to Bismarck after the storm, I saw road ditches were filled with snowdrifts laced with black streaks. Next to really bare fields, the drifts of snow were grey, not white.

It was disappointing to see so much wind erosion happening after so many years of wide spread use of no-till and minimum-till. Apparently, lots of farmers took advantage of the dry fall to work their ground more than usual.

Another time I saw evidence of erosion last year was on Dick Nissen’s farm north of Vermillion, S.D. He farms some bottom land next to the Vermillion River.

Piles of silt line a pond that collected runoff from 2,400 acres over the past 60 years.
Piles of silt line a pond that collected runoff from 2,400 acres over the past 60 years.

Nissen had cleaned the silt out of a holding pond that had been built 60 years ago on creek that drains a 2,600 acres upstream from his farm. The creek used to flood his river bottomland. When the water eventually drained away to the river, it would leave behind a thick layer of silt. Sometimes the silt would be so thick that it would kill the crop and, if it was till early enough in the growing season, he would have to replant. A small dam was built on the creek in 1961 to slow down the water and collect the silt, but the dam was often topped or as washed away a heavy rain.  In 2009, Nissen built a second bigger dam on the creek and created a larger retention pond to collect silt.

Last year, Nissen dug 55,000 yards of silt out of the smaller pond. The piles were 10-15 feet high all around the pond. He sold about 10,000 yards of the rich, black and spread the rest on his fields.

“You could see the [difference in the growth of corn] right to the line where the silt was spread. The silt was full of nutrients,” he says.

I never realized how much soil can be washed away. As Nissen said, "It can really add up."