Shifting Local Trends with Cover Crops and Short Season Corn

Shifting Local Trends with Cover Crops and Short Season Corn

Summary

SARE report – Shakopee Creek area, Tillage Radish Cover Crops

This grant was written to address a barrier in the Shakopee Watershed that cover crops cannot work in the region. The obstacles to this practice include heavy clay soils and a general culture that resists anything different. We believed that if we could convince and support a few farmers in this region to experiment with tillage radish to address the heavy soil concern, then we might be able to ignite some local curiosity and momentum.

At the onset of this grant, I had three farmers in the Shakopee Creek Watershed that were willing to dedicate a minimum of 5 acres to the use of tillage radishes following a small grain or a short season corn to see if it could help reduce the need for fall tillage in this lake bed, heavy clay soil region. Once the grant was procured, one farmer immediately backed out, realizing that the equipment he thought he could borrow would not be available to him, making the experiment relatively impossible for him with his particular time constraints and available equipment. This typifies one of the biggest barriers to experimenting in cover crops in the area. Because it is relatively exclusively corn, beans, and sugar beets, very few people have the equipment for small grain crops or cover crops, either drills for seeding or the combine equipment for harvesting. The local SWCD does have a drill for rent, but the farmers I worked with didn’t have the time to work with the SWCD for access, to go get the drill (the county is very big), or seed with a very small 8 ft. drill. (Or even have a small enough tractor to do that with.)

In 2015, one farmer who farms corn, beans, and rotates alfalfa in some of his fields agreed to try wheat and follow with a tillage radish/oats/clover mix… intending the wheat to also reseed to some degree. The radish were seeded at 2# an acre, the oats were at 40# per acre, and the clover was at 5 # per acre. These seeding rates were low, but there was also the anticipated re-seeding of the wheat. He hired a neighbor to use his equipment to plant wheat, hired that same neighbor to combine the wheat, and then borrowed another neighbor’s small drill to drill in the cover crop. The timing was correct, he planted the cover crop on July 20^th, but unfortunately the setting on the drill was NOT correct and all of the cover crop mix was planted in the headlands and the first pass on the field. It was also a very dry late summer/fall. The radish germinated, but the competition was high as the planting was so dense, and although the field was green, the radish didn’t reach pencil size.

This spring the farmer is trying again, this year planting a short season 80 day corn and intending to broadcast a tillage radish mix into the standing corn. The farmer did forgo fall tillage in order to get the most benefit possible from the cover crop. The farmer did not note any difference in tillage on the headlands versus the rest of the field, and did not think that the tillage radish accomplished much as far as compaction or drainage were concerned. Drainage was not an issue this spring, as the dry fall carried over to a dry spring.

The second participating farmer in this project has a hog and cattle operation, both on pasture, and both requiring supplemental feed and hay that is also grown on their limited acreage. Their soil is quite heavy and this farmer saw the possibility that tillage radish might be a useful addition following an annual forage crop. Annual forage crops were something new that this farmer was trying, looking for a different or better hay source than his 2 years of grasses that he included in his rotation. The farmer planted an annual forage crop in the spring of 2015 comprised of sorghum, oats, soybeans, corn, spring field peas, rape/turnip hybrid, red clover and crimson clover. He hayed this field (about 40 acres total) in the middle of July, allowed regrowth, and then grazed the field for two weeks from the middle of August until Labor Day. He then drilled tillage radish into five acres of the grazed down annual forage field at the recommended rate of 8 pounds per acre. The peas and the rape/turnip continued to flourish and grew back vigorously, and the farmer turned the cattle back onto this piece in late October to graze the last of the annual forage crop.

We found that by the first week in October, there had not been good germination of the tillage radish. It had been a very dry fall, and we thought that the combination of established plants plus limited water must have made it difficult for the radish to germinate or establish. Cattle were also run on the field when the radish still would have been quite small, which may have set them back even further. In any case, by the time it froze hard and stopped growth, it was hard to find tillage radish in those acres.

This spring the farmer tilled the acres and planted corn, and was not able to tell any difference between the ground with and without the tillage radish. He also decided he could not continue with the tillage radish experiment. First, he did not feel that the annual forage provided enough benefit, either in yield or diversity of feed, to offset the costs of seed, field time with tillage and planting, and the loss of one year of perennial hay in his rotation. He felt that it was more economically and environmentally sound to increase his hay field rotation to 3 years. However, this project did increase his interest in tillage radish as a nutrient scavenger and next year he plans to plant a short season corn, cut it for silage, and try a late season grazing mix with tillage radish in it. However, he could not get that arranged for this season, so he is not participating in the second year of the project.

Objectives/Performance Targets

Swakopee Creek region: To have 3 farmers plant at least 5 acres of tillage radish following a primary crop in the Shakopee Creek area, on the same acreage for 2 consecutive years.  

One farmer decided against participation in the spring of 2015.  The two other participants successfully planted tillage radish following wheat and an annual forage crop.

As stated above in the summary, due to dry fall, planting issues, competition and grazing, neither stand established very well. 

Accomplishments/Milestones

Both participating farmers managed to adapt their systems and rotations to include this crop.  For the farmer who followed wheat, this meant overcoming many equipment obstacles as he did not have the appropriate equipment to plant or harvest wheat, or to drill in a cover crop... nor was he accustomed to including wheat in his rotation.  But he is very interested in reducing fall tillage and he felt it was a good opportunity to push past some of those up-front barriers.  The fact that he did manage to get all of the steps in was an accomplishment.

For the other farmer with livestock who planted the tillage radish after an annual forage crop, he learned that the radish is not going to compete well with an established crop even if that crop has been grazed very hard.  He is still interested in tillage radish, but is now working on trying to adjust his corn planting and harvest to perhaps sequester more nutrients in the future. 

Impacts and Contributions/Outcomes

The impacts, beyond pushing one farmer past his comfort zone, were negligible since neither crop established well.  The best impact is that the farmer who is continuing this year has been motivated to experiment and has gotten excited about the challenge. There was no noticeable impact on compaction or drainage, but not only did the radishes  establish poorly, but this was a dry fall and spring and there was no moisture pressure.