Project Overview
Commodities
- Agronomic: annual ryegrass, clovers, medics/alfalfa
- Animals: bovine
Practices
- Animal Production: feed/forage, grazing - rotational
- Education and Training: farmer to farmer, on-farm/ranch research
- Soil Management: soil analysis, soil quality/health
Summary:
Soil health is a concern for farmers, however in Northwest Iowa cover crops are not widely used and livestock integration into a cover crop system is very rare. Organic fertilizer costs are currently over 50% of total expenses. We explored whether livestock integration to graze cover crops improves soil health and/or reduces fertilizer input costs.
Equally dividing 113 acres into 2 areas, one with cover crop only and one with cover crop and rotational grazing, allowed us to see any differences between management with or without livestock.
Our research tested soil heath before and after the cover crop and grazing rotation using the Haney and PLFA soil health tests. The Osceola County NRCS performed water infiltration tests before and after the cover crop and livestock rotation.
Our research will also take into account any increase/decrease in corn yield in 2024 from livestock integration to non livestock integration.
Research conclusions
Corn yield was higher in area that was grazed by cattle. Ten to fifteen bushel higher (see attached map)
New management practices implemented produced better soil health made minerals more biologically available. The soil came alive!
Per Haney report:
Despite high stress environment: drought 2023 and excessive moisture 2024 and later drought we saw improvements across the board in our samples.
Where cattle grazed:
- Organic matter increased 1.3% where cattle grazed. Soil respiration increased 26 ppm C where cattle grazed cover crops. We conclude that drought kept this from improving more.
- Organic nitrogen almost tripled from 7.6 ppm N to 21.6
- Conclude the depression of heavy metals especially aluminum due to higher micro activity.
- Organic Carbon rose from 139 ppm C to 227 ppm C
- Results conclude that soil is fixing more nitrogen to feed crops than before.
Per PFLA:
No results at this time.
Farmer adoption:
Andy's operation: implementation of more cover crops across all crop rotations; along with adding cattle to the crop plan. Continue to collaborate with Aaron on this farm to graze cattle as much as possible.
Aaron's operation: continue to partner with area farmer to graze cover crops
Project objectives:
March 2023, a Haney, PFLA soil health test will be completed in multiple areas of the 113 acre field to be planted. A NRCS water infiltration test will also be completed by a NRCS field agent.
April 2023, the 113 acre parcel will be planted to oats interseeded with a cover crop blend of alfalfa, red and berseem clovers, and ryegrass.
Late July, after oat harvest, the 113 acres will be divided in half to two 56.5 acre parcels. One 56.5 acre parcel will be fenced with 4 wire high tensile fencing. A water system will be installed to allow cattle to have access to water with each move they make through the parcel. On or about August 1, about 60 head of cattle will be introduced to the parcel and rotationally grazed in smaller 3 acre paddocks. Temporary paddocks will be made with plastic posts and electrified polywire. The cattle will graze the paddock of cover crop mix from it's starting height of over 12" to a height no less than 4". Then the cattle will move to the next paddock. The cattle will rotationally graze the 56.5 acres until at least November.
May 2024, corn will be planted to the 113 acres. We are hopeful that the grazed cover crop area will require less manure.
October 2024, a second Haney, PFLA soil health test will be completed in multiple areas of the 113 acre field. Only one sample was completed.
April 2025, an NRCS water infiltration test will also be completed by an NRCS field agent. We will compare the data from the 2 56.5 acre pieces. A second Haney, PFLA soil health test will be completed in multiple areas of the 113 acre field.
Objectives:
- Measure the effect of rotational cattle grazing on the soil health of an organic transitional farm.
- Successfully integrate livestock into a cover crop system which will provide the cattle with an excellent forage feed source.
- Share preliminary findings through a Practical Farmers of Iowa Field day and Pasture Walk in September
- Minimize the use of additional inputs within an Organic transition plan
- Share final findings in proposed field day in September 2025.