2017
Cover Crop Effects on Soybean Yield and Soil Properties
Contributor/Checkoff:
Category:
Sustainable Production
Keywords:
Field management Nutrient managementSoil healthTillageYield trials
Lead Principal Investigator:
Doug Shoup, Kansas State University
Co-Principal Investigators:
Ignacio Ciampitti, Kansas State University
DeAnn Presley, Kansas State University
Gretchen Sassenrath, Kansas State University
+2 More
Project Code:
1721
Contributing Organization (Checkoff):
Institution Funded:
Brief Project Summary:

The goal of this project is to evaluate the impact of five cover crop mixtures on soybean yield in a soybean-corn rotation and determining changes to soil properties over time; and to educate producers on value of cover crops through extension publications, meetings, and reports. Cover crops are utilized by more producers throughout Kansas for reduced erosion, nutrient cycling, weed suppression, reduced soil compaction, increased soil organic matter and increased biological activity. Because soybean is a legume, the impacts of nitrogen credits from a cover crop are diminished, however the other cover crop benefits need to be evaluated.

Key Benefactors:
farmers, agronomists, extension specialists

Information And Results
Project Deliverables

In the fall, five cover crop mixtures and one unplanted check will be established soon after com harvest to allow for adequate fall growth. Cover crop mixtures will be as follows 1. Unplanted treatment (weeds controlled in the fallow period)
2. Cereal rye
3. Tillage radish
4. Cereal rye+ tillage radish
5. Cereal rye + tillage radish + winter pea
6. Cereal rye + oat + tillage radish+ turnip+ winter pea+ sorghum+ crimson clover
Seeding rates of individual species will be reduced/adjusted as the number of species in the mixture increases to avoid extremely high plant populations and account for producer inputs. Experiments will be arranged in a randomized complete block design with 4 replications and planted at the KSU East Central Experiment Field in Ottawa and at the KSU Agronomy Ashland Bottoms in Manhattan. Locations are selected where soybean/com rotations and no-till practices are more prevalent. Fertility and pest control will be managed according to KSU
recommendations. Cover crops will be terminated in late April or early May with glyphosate at the onset of head emergence of the cereal rye. Soybean will be no-tilled into the standing residue in late May to early June. In the spring, soil samples will be taken for evaluation of nutrients, organic matter, and biological soil analysis (PLF A, Solvita, etc.). Soybean plots will be harvested and plot weights, moisture, and test weights will be determined. Data will be analyzed using ANOVA.

Final Project Results

Update:
Please see attached PDF

View uploaded report PDF file

A research study was established in 2011 in a soybean and corn rotation with cover crops planted soon after each crop harvest in the fall. A variety of complex cover crop mixtures were evaluated ranging from single specie to 7 specie mixtures. Cover crops were terminated in the spring soon after anthesis of the cool season cereal in the cover crop. Soybean yield responded differently among the four years of the study. In an extreme drought year of 2012 the unplanted check yielded 29.4 bu/a. Soybean yield was significantly reduced by 4.2 and 3.4 bu/a in treatments with wheat or turnip cover crop, respectively. In 2014, the unplanted check yielded 33.9 bu/a and cover crop treatments rye, rye + radish, and >6-species mix had significantly greater soybean yield at 3.7, 3.4, and 3.3 bu/a, respectively. In 2015, only the rye cover crop treatment significantly reduced soybean yield compared to the unplanted check at a 4.2 bu/a yield loss. No significant yield differences were observed in any cover crop treatment in 2016.

The United Soybean Research Retention policy will display final reports with the project once completed but working files will be purged after three years. And financial information after seven years. All pertinent information is in the final report or if you want more information, please contact the project lead at your state soybean organization or principal investigator listed on the project.