The short answer: a region of rolling, asymmetrical hills, composed of loess that lies principally in Idaho’s Latah County and Washington’s Whitman and Spokane Counties.
But that answer doesn’t begin to describe the mystery of the Palouse. If you look closely at the lovely rolling landscape, you will notice that there are no continuous valleys, and the hills do not connect to make long ridges. In other words, these hills were not created by rivers and streams.
If you said they look more like sand dunes, you would be correct! And if you hypothesized that all this loess, or wind-blown silt, blew in from someplace else, you would also be correct!
Geologists say that this land of isolated humps and hollows is best thought of as a sea of wind dunes, blown in from perhaps the Pasco Basin, at a time when the climate had dried up ancient Lake Lewis. Prehistoric dust storms from the south west then carried the fine silt from the dried-up lake bed toward the Palouse. One hypothesis suggests that the fine dust particles were trapped when they hit the wetter grasslands of the Palouse.
The steepest slopes in the Palouse tend to be on the sides of the hills facing northeast. It is typical for dunes to form their steepest slopes in the direction of their movement.
Some have estimated that, at today’s wind speed, it would take at least 25,000 years to create an eighty foot hill of loess. Who knows how long it took to create the Palouse. But even today, dust storms in the Palouse can reduce visibility and turn the sun a gossamer color.
The Palouse covers approximately 4,000 square miles and lies primarily in Idaho’s Latah County and Washington’s Whitman and Spokane Counties. It stretches from north of Lewiston to almost the southern end of Lake Coeur d’Alene.
In the 1860’s and 1870’s settlers descended upon the Palouse country, forcing out Native Americans and plowing up the native grasses. By the 1920’s farmers could safely boast that the Palouse produced more wheat per acre than any other region its size in the world!
It also produced more skilled teamsters than any other place in the world, as farmers hitched teams of horses to combines to harvest the golden dunes of grain. In the 1930’s tractors began replacing the horses.
Today, the Palouse still is the world’s leader in the production of soft white winter wheat. The combination of mild winters, wet springs and dry summers creates the ideal conditions for the crop. The loess soil retains spring moisture well, allowing the winter wheat to prosper even without summer rains.