With all of the rain we have received over the last two weeks, soil erosion issues on raised beds have developed. I have looked at several corn and grain sorghum fields that, from the road, appear to be okay (not flooded or hail-damaged). They appear to be windblown and leaning to some degree, but your first impression is that the fields are okay. However, on closer inspection, there are some serious problems.
In some instances, soil erosion from the raised beds has been severe enough that much of the plant root system is exposed. Essentially, the beds have melted away from all the rain. Corn that was originally planted 2 inches deep now may have the seed sitting on the soil surface. This problem is more common on sandy soils or fields planted using twin row planters. The twin row planting is worse because the rows were already on the edge of the bed prior to the rain. Corn or grain sorghum planted on 30 inch rows also appears to be hurt worse, likely because of a smaller/narrow raised bed prior to the rain. Below are some examples of the problems we are seeing.
What do we do now?
Leaving the roots exposed and hoping for the best is not a good option. Since the plants are essentially shallow planted now, roots will not develop properly, which will lead to lodging problems later in the season. Some fields have so much of the root system exposed that it is doubtful that a normal plant will develop if nothing is done.
One approach to help solve this problem would be to cultivate to throw soil back up around the base of the plant – essentially trying to cover the roots back up. This approach may work in some instances, especially if the plants are fairly large and standing up. However, for plants that are not standing up or are very small cultivating may not be an option. Some grain sorghum fields I inspected were in such bad shape that the only solution would be to replant. Several corn fields have been/or will be replanted because of these problems.
What could have been done to prevent this problem?
Ultimately, in many instances, not much could have been done to prevent this with the high amount of rain we received. No-till fields appear to be in better shape than conventional tilled fields with similar soil types. Clay soils, overall, are not seeing much of this problem.