Abstract
Cover crops, plants grown during the fallow period between cash crop growing seasons, have gained increasing amounts of attention throughout the agriculture industry in recent years. Many producers use them to reduce soil erosion, scavenge nutrients, and improve soil structure, water infiltration, and soil health, but questions still remain on maximizing cover crop benefits while simultaneously maintaining or improving cash crop production. This study measured cover crop and no-tillage effects on soil nitrogen and cash crop yield across multiple sites in Indiana beginning in fall 2015 and ending in fall 2017, typically in a corn (Zea mays L.)/soybean (Glycine max L. Merr.) rotation. Many of the sites had utilized cover crops for at least three to four years by fall 2015 as part of the Conservation Cropping Systems for Soil Health and Productivity (CCSSHP) Project, which was initiated in fall 2012. Cover crops generally reduced soil nitrate-N levels compared to no cover crops in the fall when good cover crop growth occurred. The same trend occurred in the spring, again when cover crops had good growth and did not winter kill. Cover crops did not negatively influence cash crop yields in fall 2016 or fall 2017. In addition, in 2017 a subset of three sites comparing cover crops versus no cover crops in no-tillage, and one with a tillage and no cover crop conventional neighbor, were selected for an in-depth look at soil health indicators across five sampling dates during the cash crop growing season. In previous years of the study, soil health indicators were measured once yearly at V3-V6 growth stages in corn. In order to determine if sampling at that time was ideal for detecting real differences in soil health indicators between cover crop and no cover crop treatments, four additional sample times were selected for comparison. The indicators discussed included active carbon and soil respiration, as measured by the Cornell Comprehensive Assessment of Soil Health (CASH), as well as arbuscular mycorrhizal fungi (AM-fungi), gram positive bacteria, gram negative bacteria, non AM-fungi, fungi:bacteria ratio, actinobacteria, protozoa, and total PLFA, which is used as an estimate of total microbial biomass, as measured by a PLFA analysis conducted by the University of Missouri Soil Health Assessment Center. Results indicated that sampling time selection should be chosen based on the goals of the sampler. To find differences between a cover crop and no cover crop comparison, when ample cover crop biomass growth occurs in the spring, sampling at V3-V6 growth stages in corn may be best. To detect the highest values throughout the whole season, particularly in indicators measured in the PLFA analysis, sampling at the end of the season after cash crop harvest may be best.
Abstract from the paper’s OpenAlex record, shown for indexing and research. Copyright remains with the authors or the publisher. Read at the source ↗
The text the model read, with the source record’s inline markup (italics, sub- and superscripts) rendered and its character entities decoded; quote offsets refer to the raw text.
Claims 6
Claim · model-written summary
Cover crops reduced fall soil nitrate-N versus no cover crops when cover crop growth was good.
- Taxon
- corn
Zea mays subsp. mayse1 - Treatment
- Cover cropse0
- Outcome
- soil nitrate-N levelse0
- Direction
- reducede0
- Qualifier
- in the fall when good cover crop growth occurrede0
- Comparator
- no cover cropse0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Cover crops generally reduced soil nitrate-N levels compared to no cover crops in the fall when good cover crop growth occurred.”
e1“corn (Zea mays L.)/soybean (Glycine max L. Merr.) rotation”
Claim · model-written summary
Cover crops also reduced spring soil nitrate-N when growth was good and they did not winter kill.
- Taxon
- cornZea mays subsp. mayse2
- Treatment
- cover cropse0
- Outcome
- soil nitrate-N levelse1
- Direction
- reducede1
- Qualifier
- in the spring, again when cover crops had good growth and did not winter kille0
- Comparator
- no cover cropse1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“The same trend occurred in the spring, again when cover crops had good growth and did not winter kill.”
e1“Cover crops generally reduced soil nitrate-N levels compared to no cover crops”
e2“corn (Zea mays L.)/soybean (Glycine max L. Merr.) rotation”
Claim · model-written summary
Cover crops did not negatively influence cash crop yields in fall 2016 or 2017.
- Taxon
- cornZea mays subsp. mayse1
- Treatment
- Cover cropse0
- Outcome
- cash crop yieldse0
- Direction
- did not negatively influencee0
- Qualifier
- fall 2016 or fall 2017e0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Cover crops did not negatively influence cash crop yields in fall 2016 or fall 2017.”
e1“corn (Zea mays L.)/soybean (Glycine max L. Merr.) rotation”
Claim · model-written summary
The authors recommend choosing soil health sampling time according to sampling goals.
- Taxon
- cornZea mays subsp. mayse1
- Outcome
- sampling time selection should be chosen based on the goals of the samplere0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“sampling time selection should be chosen based on the goals of the sampler”
e1“corn (Zea mays L.)/soybean (Glycine max L. Merr.) rotation”
Claim · model-written summary
For finding cover crop differences with ample spring biomass, sampling corn at V3-V6 may be best.
- Taxon
- cornZea mays subsp. mayse0
- Outcome
- sampling at V3-V6 growth stages in corn may be beste0
- Qualifier
- when ample cover crop biomass growth occurs in the springe0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“when ample cover crop biomass growth occurs in the spring, sampling at V3-V6 growth stages in corn may be best”
Claim · model-written summary
To detect the highest seasonal soil indicator values, sampling after harvest may be best.
- Taxon
- cornZea mays subsp. mayse1
- Outcome
- sampling at the end of the season after cash crop harvest may be beste0
- Qualifier
- particularly in indicators measured in the PLFA analysise0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“To detect the highest values throughout the whole season, particularly in indicators measured in the PLFA analysis, sampling at the end of the season after cash crop harvest may be best.”
e1“corn (Zea mays L.)/soybean (Glycine max L. Merr.) rotation”
The same questions in other papers
cover crop · nutrient: content · Zea mays (maize)Positive and negative results
23 papers in the same direction as this paper · 12 in the opposite direction
- no effect
- negative
- no effect
32 papers more in this group
See all 36 papers →cover crop · yield · Zea mays (maize)Positive and negative results
117 papers in the same direction as this paper · 104 in the opposite direction
- positive
- positive
- positive
218 papers more in this group
See all 222 papers →Claims are grouped by organism, treatment and what was measured or targeted. A paper counts as positive when any of its claims in the group is positive.