Wheat harvest is progressing as this is written and if the Thursday night storms hold off, harvest should be in full swing. And before discussing wind erosion, Happy Fathers’ Day to all the dads out there. Today we will start to tackle wind erosion. If you think soil erosion is soil erosion you would be wrong. While there are some similarities and both remove valuable soil particles, water and wind erosion differ in major ways. So today we will discuss wind erosion mechanisms. And remember that areas like Western Kansas experience both types of erosion and in fact damage from water erosion can be worse in an area like ours than in the traditional Corn Belt.
Wind erosion is the physical relocation of sand, silt, and clay, naturally by wind. This problem is worse in arid and semi-arid areas because of less vegetative growth, less organic matter accumulation and less soil development (less clay and more sand and silt sized particles). Before discussing wind erosion, one principle is key – wet soils don’t blow.
The three phases of wind erosion are detachment/abrasion, transportation, and deposition. Detachment has a snowball effect. Once a few soil particles break loose, they break loose more soil particles which break loose more and so on.
Transportation, the movement of soil particles is determined by the size of the soil particle. The larger the particle the less distance it will travel. The three types of transportation are:
1. Saltation – movement of soil particles by a series of short bounces along the soil surface. This is 50 – 90% of total soil movement, especially sand sized, larger particles. These particles cause other particles to become dislodged and move.
2. Soil Creep – next step after saltation. Rolling or sliding of larger soil particles along the soil surface. Particles up to about 1 mm in diameter and 5 – 25% of soil movement.
3. Suspension – fine-sized sand and smaller particles. These get up into the atmosphere and stay there. Once suspended these particles can be transported thousands of miles. This resulted in the Dust Bowl in the 1930s and the dust storms we experience today.
Deposition, where the particles end up is a function of their size. The smaller the particle the further is can be transported. It may be a tens of feet as in saltation, hundreds of yards with soil creep, and thousands of miles with suspension. For saltation and soil creep, particles are deposited when the wind speed is insufficient to move them. For suspension, particles will stay suspended until an event like rain deposits them. One last item to keep in mind, as the wind picks up past the threshold velocity where movement occurs, soil moves to the cube of the velocity. So as the wind speed increases say from one to two, it increases movement by a factor of 8, not 2. Next week, how to control wind erosion.

Dr. Victor L. Martin is the agriculture instructor/coordinator for Barton Community College. He can be reached at 620-792-9207, ext. 207.