ISSUE 6 June 7, 2001
CONSIDER COVER CROPS FOR WET FIELDS
It will be very important when fields have not been seeded to crops due to excessive water that some type of cover crop is seeded. There are three reasons for this. The first is for soil conservation. Soil will blow away if repeatedly beaten into fine particles through clean, fallow-style tillage. What it has taken hundreds of years for good stewardship to produce can be blown away in an afternoon. Secondly, there is no reason to save any more water than we already have through fallow. Water tables in the north east part of the state in particular are already excessively high. A cover crop will use up some of that water so the risk of having a repeat prevented planting next year will be reduced. Thirdly, high water tables and excessive moisture are the ingredients to losing more land through salt buildup. If the water is not used up and water tables drawn down, salinization is likely.
The main considerations when choosing a cover crop are its ability to survive adverse soil conditions (wet soils in our case), ability to withstand potential heat associated with late planting, ability to remove moisture from the soil, and a seed availability. Potential cover crop choices include; barley, spring Triticale, millet, buckwheat, Sudan grass/forage sorghum, sweet clover (for saltier sites), and vetches such as Hungarian.
With most of these crops obtaining seed will be the major challenge, barley being the exception. Most of these crops can be planted up to June 20th as cover crops with success. As late June approaches millet, buckwheat, and Sudan grass are probably some better choices. With some limitations these can be harvested for forage but should generally be considered as green manure crops. Seeding rate information for these crops can be found on the NDSU ProCrop data base at:
NDSU Extension Soil Specialist
Michael D. Peel
NDSU Small Grains Extension Agronomist