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The Wondrous Soil Of The Red River Valley


The topography of the Red River Valley is very simple, it is VERY flat. The soil of the Red River Valley is perhaps not so well known as the topography, however. The soil underfoot is very deep and rich stuff, and it is the most fertile topsoil in North Dakota. This is because the valley was once the bottom of glacial Lake Agassiz. As the great glaciers melted, rivers brought sediments – clay, silt, sand and gravel, into the huge lake. The gravel and sand dropped to the lake near the mouth of the rivers, but the finer materials settled into the middle of the lake.

As Lake Agassiz’s basin filled with sediment, bulrushes and aquatic plants grew in its shallower waters. Each year, those plants lived and died and fell and decayed, further filling the lakebed. Eventually, Lake Agassiz dried up and was drained by the Red River.

The soil is very deep. The alluvial soil depth at Grand Forks, including topsoil, loam and clay, is “fifty to seventy-five feet deep,” and under that lies cretaceous shale 300-feet thick – over granite or gneiss bedrock.

The soil is so good that it became subject to exaggeration, as in an article in the Minneapolis Tribune, on this date in 1922. Charles Collisson, the agricultural editor, said the Red River Valley topsoil was the “blackest soil it is possible to imagine: soil the color of chocolate icing and looking as if it were good enough to eat. … Should you put some of this soil in your mouth, you will be surprised to find that it contains practically no grit, and no wonder, when you learn that this is the residue of the reeds and rushes which grew up and fell over and rotted year after year, in the days when the lake was passing from the frog-pond stage to prairie pasture … Thus the top layer is almost pure humus; a great natural garden 600 miles long and from 25 to 560 miles wide.”

Some might say this was pure hubris – praising the chocolate-frosting quality of the Red River Valley’s topsoil. Still, modern-day people might take a moment to appreciate the deep and rich soil that makes the region prosper. Maybe you could taste it, but don’t eat it.

Dakota Datebook written by Dr. Steve Hoffbeck, MSU Moorhead History Department.

Sources: Charles F. Collisson, “Red River Valley, Famous for Wheat, Turns to Dairying,” Minneapolis Morning Tribune, July 23, 1922, p. D8.

“Physiography Of N. Dakota,” Grand Forks Daily Herald, February 16, 1915, p. 8.

Charles A. Jensen and N.P. Neill, “Soil Survey of the Grand Forks Area, North Dakota,” Biennial Report of the Director of the Agricultural College Survey of North Dakota to the Governor of North Dakota (Bismarck: Tribune, State Printers and Binders, 1904), p. 37, 38, 39.