Table 1 illustrates the effect of installing barriers in a cropland field. Conservation compliance systems providing equivalent soil loss 1 in Lincoln County, Colorado. The predicted soil loss equals 14 tons annually per acre. The barriers consisted of seven rows of grain sorghum. Residues were present during the critical period, November through April.
Taller plants provide more protection than shorter plants when used at the same spacing.
When annual plants such as corn, sorghum, or millet are used for barriers, the plants must be in place during the critical erosion period in order to be effective. In Colorado, the critical erosion period from wind is generally from November through April. Consequently, such annual barriers need to be planted in May or June and left undisturbed through the following April. Ridging as an effective barrier. Here a deep furrow drill creates ideal ridges.