Comment: 24:00 - 24:59 (00:59)
Source: Annenberg/CPB Resources - Earth Revealed - 15. Weathering and Soils
Keywords: "Wayne Soppeland", weathering, soil, wind, windbreak, erosion, "conservation tillage", tilling, percolation, water, crop, irrigation
Our transcription: But windbreaks are not the total answer to erosion problems.
A technique called, conservation tillage, has also proved to be especially useful.
Tilling, or plowing the fields, is routinely done to prevent the formation of residues which block the percolation of water through the soil.
But if too much tilling is done, the soil is so frequently loosened that much of it can be blown or washed away.
In other words, instead of plowing the soil and disking it a number of times leaving it completely exposed, we do as little as possible.
We will disk once leaving as much stubble on the ground, so that if a wind storm comes up during that time, very little dirt is moving.
And then we get back in and try to plant the next crop as soon as possible and begin the irrigation.
So that the period of time that the soil is exposed is very minimal.
Geology School Keywords