Crop Production and Soil Properties Impacts of Integrating Annual Forages and Ruminant Livestock into Wheat-Based Cropping Systems

Authors

Zachariah C. Carson, Kansas State UniversityFollow
Augustine K. Obour, Kansas State UniversityFollow
John D. Holman, Kansas State UniversityFollow
Logan Simon, Kansas State UniversityFollow
Kraig L. Roozeboom, Kansas State UniversityFollow

Keywords

annual forages, grazing, soil properties

Abstract

Integrating annual forages and ruminant livestock to intensify dryland cropping systems can increase profitability, increase water use efficiency, and improve soil health. The objective of this study was to determine the crop yield and soil property impacts of intensifying traditional no-till winter wheat (Triticum aestivum L.)-grain sorghum (Sorghum bicolor Moench)-fallow (WW-GS-F) with annual forages as well as integrating livestock to graze forages and crop residues. This study was initiated in 2021 at the Kansas State University Agricultural Research Center-Hays in Hays, KS. Treatments were WW-GS-F (control), WW-GS-F with grain sorghum residues grazed, winter wheat/forage sorghum-forage sorghum-fallow (WW/FS-FS-F) with forage sorghum grazed, and WW/FS-FS-F with forage sorghum hayed. The treatments were replicated four times with all phases of the rotation present each year. Grain yields were determined in 2023 and 2024, while forage yields were determined every year with sampling to characterize soil properties in the fall of 2023 and 2024. Results showed that full-season forage sorghum harvested for hay produced 5255 lb/a on average, while post-wheat forage sorghum harvested for hay produced 2042 lb/a. Before grazing, full-season forage sorghum produced 8617 lb/a with about 51% of biomass remaining as residue after livestock were removed. On average, post-wheat forage sorghum produced 3399 lb/a before grazing. Because of smaller yields, post-wheat forage sorghum plots were grazed in only 2 years when 46% of biomass remained as residue on the plots after livestock were removed. In 2023 and 2024, WW yields averaged 16 bu/a due to dry weather, with no difference among treatments. Averaged across 2023 and 2024, the WW/FS-FS-F (grazed) treatment had greater crop residue cover (78%) at winter wheat planting than all other treatments (63%). No differences in bulk density in the 0- to 2-inch and 2- to 6-inch soil depths were observed across treatments. While penetration resistance did not show any differences in the top 0- to 2-inch depth, there was a significant decrease in penetration resistance in the 2- to 6-inch depth with WW/ FS-FS-F treatments. Despite no differences in bulk soil organic carbon (SOC) in the 0- to 2-inch and 2- to 6-inch soil depths, dry and wet aggregate associated SOC was significantly greater with WW-GS-F (grazed) and WW/FS-FS-F (grazed) treatments than WW-GS-F and WW/FS-FS-F (hayed). No differences in mean weight diameter (MWD) of water stable aggregates or the wind-erodible fraction were observed across treatments. These preliminary results suggest that intensifying the WW-GS-F rotation 2 with annual forages and integrating livestock increased available forage, soil residue cover, and aggregate associated organic carbon with no effect on winter wheat yields.

Recommended Citation

Carson, Zachariah C.; Obour, Augustine K.; Holman, John D.; Simon, Logan; and Roozeboom, Kraig L. (2025) "Crop Production and Soil Properties Impacts of Integrating Annual Forages and Ruminant Livestock into Wheat-Based Cropping Systems," Kansas Agricultural Experiment Station Research Reports: Vol. 11: Iss. 4. https://doi.org/10.4148/2378-5977.8716