No Till Notes: 'Rotations'

The final stop on our tour at the Dakota Lakes Research Farm in Pierre, S.D., was a look at the dry land portion of the farm. I’ve always felt dry land farming is much more interesting than irrigated farming. The ability to irrigate can mask some deficiencies in cropping rotation and soil health.

On dry land acres, there is much less room for error. Proper management of crop rotations is critical to the success of a continuous no-till cropping system. Lack of carbon inputs, lack of sufficient residues to protect the soil surface, poor crop diversity and insufficient intervals between like crops can all have a detrimental effect on how successful the system operates.

Properly managed rotations will build soil health which improves water infiltration, soil structure, microbial activity, and overall soil performance. These rotations will build soil health over time which will reward the continuous no till crop producer with improved profitability of their operation. Properly managed rotations will also help break up persistent weed and disease cycles leading to the production of healthier crops.

I visited with Dwayne Beck, manager of the Dakota Lakes Research Farm, about his choice of crop rotations on his dry land acres. Beck was quick to point out that there is no standard rotation on their farm. The do have set rotations which they designed for their farm early in the development of the farm to study how rotations over long periods responded. Three rotations on their main farm have been in place since the beginning of the farm operation in 1990.

These rotations have been ongoing since that time and there is a lot of value in research conducted over this time period. Rotations lacking in carbon inputs began to lag behind rotations designed with higher carbon inputs over extended periods of time. I think it is imperative that agricultural research be designed as a systems approach studied over long intervals. It is difficult today to find research conducted over extended periods of time due to the way in which research is funded.

A few of my observations since I last visited Dakota Lakes Research Farm is the addition of a couple of crops into the cropping rotations. Beck is always looking for new crops which fit our growing conditions for this region and match up well with good crop rotations.

Beck has incorporated more flax into his cropping rotations. Flax has been around for a long time and I think it is used primarily as oil for crushing. Flax is a good fit for a cool season broadleaf in some crop rotations. Marketing of flax would be an obstacle for producers in our area.

He is also using flax as a cover crop following field peas. Flax is seeded shortly after field pea harvest. The idea behind seeding the flax is to produce a cover crop prior to winter wheat seeding that will add ground cover and vertical structure to the field pea residue. Flax grows upright and produces an elongated firm stem which will aid in wind erosion control and provides the vertical structure need to catch snow over the winter months. Winter wheat is seeded through the growing flax.

Beck is also growing teff grass that is a C4 grass similar to corn. The teff grass is grown for seed production and may be a good fit for our region. The teff grass seed is highly valuable and the possibility of producing it in our region as an alternative to dry land corn may be an option.

I think there may be some grazing potential following seed harvest with teff grass. Marketing the harvested seed would be the challenge for producers in our area. Other obstacles such as crop insurance would also have to be taken into consideration.

Next week I’ll take a look at some of Beck’s crop rotations on his dry land farm.