Due to excessive rainfall last fall, and wet field conditions in certain parts of North Dakota, there will be considerable prevent plant acres this summer. Prevent plant payments help farmers through tough times, but most farmers would agree that planting and harvesting a crop is far more preferable than receiving a sustenance from a federal check.

Due to excessive rainfall last fall, and wet field conditions in certain parts of North Dakota, there will be considerable prevent plant acres this summer. Prevent plant payments help farmers through tough times, but most farmers would agree that planting and harvesting a crop is far more preferable than receiving a sustenance from a federal check.

The choice of not planting anything on prevent plant acres in 2020 will make those fields far more likely to be prevent plant acres in 2021. Use of a cover crop does not come free, but the probability of being able to plant a profitable crop next year after a cover crop will be much greater than leaving the land fallow.

A great deal of information regarding the use of cover crop on prevent plant acres can be found on the NDSU Soil Health Website at https://www.ndsu.edu/soilhealth/ (“Cover Crops on Prevented Planting Acres” link on home page). There are a number of short videos posted, links to RMA information, as well as associated articles that will be helpful when planning for cover crop treatment of prevent plant acres.

In addition, several on-line Café Talk discussions are planned through June 24 where producers and their consultants can ask questions directly about specific circumstances.  The schedule and zoom call link are also posted on the NDSU Soil Health Website along with recordings of each of the discussions.

Questions from producers have already begun. Here are a few, paraphrased:

Q. I am a canola producer and worry that a cereal with a forage radish and or turnip may increase the chance of certain diseases for canola in my rotation. Is that true?

A. Unfortunately, forage radish and turnip, being mustard-family plants like canola, can be a host for clubroot pathogen, and using these cover crops in a mix would be a mistake for farmers with canola in their rotation. A cereal grass, such as oat, barley, rye or a mix of oat/barley or a warm season grass if planting in late June or July would be good cover crop choices. A straight cereal would make any herbicide treatment for broadleaf weeds possible if it were needed.

If weed pressures are not a major concern, use oats, barley, field peas and sugarbeets if looking to use a diverse mix. On areas with some salinity issues, use sweet clover instead of field peas in the mix.  Please note that sugarbeets do not compete well, so increasing the percentage of sugarbeet seed in a mix will improve results.

Q. When would be a good time to seed a cover crop?

A. Seeding time would depend first on when it was possible to enter the field. A cover crop seeding with seeding equipment will more likely achieve a good stand compared to flying it on and hoping for a rain, or broadcasting seed with ground equipment and working it in. Also, if short-season crops were put in early, termination to prevent seed production might be required, so checking with FSA on their rules would be wise. 

To prevent seed production (or bolting) on many cover crop species, especially radish, seeding after July 15 is desirable.  When seeded earlier, radish can go to seed and then they won’t put on the thick root for breaking any compaction. Depending on soil moisture and field conditions for best above-ground and below- ground growth, cover crops should be planted between July 15 to August 5. That will especially be true for northeastern ND. 

However, in grower discussions at one winter Café Talk, there may be a need by some to have a continuous summer cover to hold down weeds and use excessive moisture. If cover crop is seeded early, it might be necessary to terminate the cover crop midway through the summer to prevent bolting or heading, and then seed the 2nd cover crop into the field.

Q. Will the cover crop take up too much soil moisture and leave me vulnerable to drought if it is a dry summer?

A. A field that had to be prevent plant is an indication that there is too much water there already; therefore, using some water before fall would be a very good idea. Using a shovel later in the season after the cover crop is growing will give you an idea how deep the moisture is. If it's only dry on the surface, but the subsurface is still wet, letting the cover crop continue to grow will be beneficial next season. If the subsoil is also dry and the long-term forecast calls for dry, then terminating the cover crop before freeze-up would make sense.

Q. If a cover crop produces too much biomass, would that produce planting issues next spring?

A. You should have a plan for dealing with biomass at the time of planting. Some cover crops have the potential for producing large amounts of biomass that if not managed may result in problems next spring. Since regulations do not permit haying and grazing until after November 1st, managing residues may mean cutting or terminating some actively growing species much earlier than when they may be killed by fall frost.

If the long-term weather forecast for next spring indicates dryness, increased cover crop biomass can help catch more snow and provide spring moisture for good crop establishment and early growth. If the forecast indicates that another wet spring is likely, a densely growing cover crop can dry down the soils in the fall to provide better trafficability for the next spring.

The more extensive root system of a vigorous cover crop will also improve soil water infiltration during the spring. In addition, choosing a mix with a lower C:N ratio can help breakdown the cover crop residue.