Abstract
A 2-yr field study was conducted during 1998 and 1999 at Stoneville, MS, on a Dundee silt loam to determine weed control, yield, and net return associated with winter cover crops in soybean. Cover crop systems included Italian ryegrass, oat, rye, wheat, hairy vetch, crimson clover, subterranean clover, no-cover crop conventional tillage (CT), and no-cover crop no-tillage (NT), all with standard preemergence (PRE), postemergence (POST), PRE POST, and no-herbicide weed management. Oat (11.1 Mg/ha) had highest dry biomass compared to all other cover crops (6.0 to 7.6 Mg/ha) at soybean planting. Biomass decreased 9 wk after planting (WAP) compared to the respective biomass at soybean planting in all cover crops. Italian ryegrass and rye biomass decay was slow and about two-thirds of plant residue persisted at 9 WAP. Cover crops had no effect on densities of barnyardgrass, prickly sida, and yellow nutsedge, but altered the density of browntop millet. Total weed biomass was higher in rye, wheat, and subterranean clover than in Italian ryegrass cover crop systems, and higher with the PRE-only vs. POST-only or PRE POST programs at 10 WAP soybean. Soybean yield decreased in the order of no-cover crop NT ≥ no-cover crop CT ≥ hairy vetch ≥ crimson clover ≥ rye ≥ oat ≥ wheat ≥ subterranean clover > Italian ryegrass. None of the cover crop systems gave soybean yield higher than the no-cover crop CT system in the absence of herbicides. Under a PRE-only program, all cover crop systems had lower yield compared to the no-cover crop CT system. When late-emerged weeds were controlled with POST applications (POST-only or PRE POST programs), all cover crops, except Italian ryegrass, had no detrimental effect on soybean yields, which were not different from no-cover crop CT plots. In cover crops, input costs were high due to additional cost of seeds, planting, and desiccation. Net return was highest in no-cover crop NT ($105/ha) followed by no-cover crop CT ($76/ha) system. Net returns were negative for all cover crops and losses were highest in crimson clover (−$62/ha) and subterranean clover (−$161/ha).Nomenclature: Barnyardgrass, Echinochloa crus-galli (L.) Beauv. #3 ECHCG; browntop millet, Brachiaria ramosa (L.) Stapf # PANRA; prickly sida, Sida spinosa L. # SIDSP; yellow nutsedge, Cyperus esculentus L. # CYPES; crimson clover, Trifolium incarnatum L. ‘Dixie’; hairy vetch, Vicia villosa Roth; Italian ryegrass, Lolium multiflorum Lam. ‘Gulf’; oat, Avena sativa L. ‘Bob’; rye, Secale cereale L. ‘Elbon’; soybean, Glycine max (L.) Merr. ‘DP 3588’; subterranean clover, Trifolium subterraneum L. ‘Mount Barker’; wheat, Triticum aestivum L. ‘Cocker 9803’.Additional index words: Allelopathy, conventional tillage, herbicide, integrated weed management, mulch, net return, no-tillage, weed emergence, weed biomass.Abbreviations: ANOVA, analysis of variance; CT, conventional tillage; NT, no-tillage; POST, postemergence; PRE, preemergence; WAP, weeks after planting soybean.
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 20
Claim · model-written summary
Oat had the highest cover crop biomass at soybean planting.
- Taxon
- Oat
Avena sativae0 - Outcome
- dry biomasse0
- Direction
- higheste0
- Value
- 11.1 Mg/hae0
- Qualifier
- 6.0 to 7.6 Mg/hae0
- Comparator
- all other cover cropse0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Oat (11.1 Mg/ha) had highest dry biomass compared to all other cover crops (6.0 to 7.6 Mg/ha) at soybean planting”
Claim · model-written summary
All cover crop biomass decreased by nine weeks after soybean planting.
Verbatim
e0“Biomass decreased 9 wk after planting (WAP) compared to the respective biomass at soybean planting in all cover crops”
Claim · model-written summary
About two thirds of Italian ryegrass residue persisted at nine weeks.
- Taxon
- Italian ryegrass
Lolium multiflorume0 - Outcome
- plant residue persistede0
- Value
- about two-thirdse0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Italian ryegrass and rye biomass decay was slow and about two-thirds of plant residue persisted at 9 WAP”
Claim · model-written summary
About two thirds of rye residue persisted at nine weeks.
- Taxon
- rye
Secale cerealee0 - Outcome
- plant residue persistede0
- Value
- about two-thirdse0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Italian ryegrass and rye biomass decay was slow and about two-thirds of plant residue persisted at 9 WAP”
Claim · model-written summary
Cover crops did not change densities of barnyardgrass, prickly sida or yellow nutsedge.
- Taxon
- soybean
Glycine maxt0 - Treatment
- Cover cropse0
- Interactor
- barnyardgrass, prickly sida, and yellow nutsedgee0weed
- Outcome
- densities of barnyardgrass, prickly sida, and yellow nutsedgee0
- Direction
- no effecte0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Cover crops had no effect on densities of barnyardgrass, prickly sida, and yellow nutsedge”
t0“Soybean”
Claim · model-written summary
Cover crops altered browntop millet density.
- Taxon
- soybeanGlycine maxt0
- Treatment
- Cover cropse1
- Interactor
- browntop millete0weed
- Outcome
- density of browntop millete0
Not reportedComparatorDirection
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“but altered the density of browntop millet”
e1“Cover crops had no effect on densities”
t0“Cover Crop Residues on Weeds, Yield, and Net Return in Soybean”
Claim · model-written summary
Rye cover systems had higher total weed biomass than Italian ryegrass systems.
- Taxon
- soybeanGlycine maxt0
- Treatment
- ryee0
- Interactor
- weede0weed
- Outcome
- Total weed biomasse0
- Direction
- highere0
- Comparator
- Italian ryegrass cover crop systemse0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Total weed biomass was higher in rye, wheat, and subterranean clover than in Italian ryegrass cover crop systems”
t0“Soybean”
Claim · model-written summary
Wheat cover systems had higher total weed biomass than Italian ryegrass systems.
- Taxon
- soybeanGlycine maxt0
- Treatment
- wheate0
- Interactor
- weede0weed
- Outcome
- Total weed biomasse0
- Direction
- highere0
- Comparator
- Italian ryegrass cover crop systemse0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Total weed biomass was higher in rye, wheat, and subterranean clover than in Italian ryegrass cover crop systems”
t0“Soybean”
Claim · model-written summary
Subterranean clover cover systems had higher total weed biomass than Italian ryegrass systems.
- Taxon
- soybeanGlycine maxt0
- Treatment
- subterranean clovere0
- Interactor
- weede0weed
- Outcome
- Total weed biomasse0
- Direction
- highere0
- Comparator
- Italian ryegrass cover crop systemse0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Total weed biomass was higher in rye, wheat, and subterranean clover than in Italian ryegrass cover crop systems”
t0“Soybean”
Claim · model-written summary
PRE-only herbicide programs had higher weed biomass than POST-only or PRE POST at ten weeks.
- Taxon
- soybeanGlycine maxe0
- Treatment
- PRE-onlye0
- Interactor
- weede1weed
- Outcome
- weed biomasse1
- Direction
- highere0
- Comparator
- POST-only or PRE POST programse0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“higher with the PRE-only vs. POST-only or PRE POST programs at 10 WAP soybean”
e1“Total weed biomass was higher”
Claim · model-written summary
Soybean yield followed the reported order from no-cover NT to Italian ryegrass.
- Taxon
- SoybeanGlycine maxe0
- Outcome
- Soybean yielde0
- Direction
- decreasede0
- Qualifier
- no-cover crop NT ≥ no-cover crop CT ≥ hairy vetch ≥ crimson clover ≥ rye ≥ oat ≥ wheat ≥ subterranean clover > Italian ryegrasse0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Soybean yield decreased in the order of no-cover crop NT ≥ no-cover crop CT ≥ hairy vetch ≥ crimson clover ≥ rye ≥ oat ≥ wheat ≥ subterranean clover > Italian ryegrass”
Claim · model-written summary
Without herbicides, no cover crop increased soybean yield above no-cover conventional tillage.
- Taxon
- soybeanGlycine maxe0
- Treatment
- cover crop systemse0
- Outcome
- soybean yielde0
- Direction
- Nonee0
- Qualifier
- absence of herbicidese0
- Comparator
- no-cover crop CT systeme0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“None of the cover crop systems gave soybean yield higher than the no-cover crop CT system in the absence of herbicides”
Claim · model-written summary
Under PRE-only, all cover crops yielded less than no-cover conventional tillage.
- Taxon
- soybeanGlycine maxt0
- Treatment
- all cover crop systemse0
- Outcome
- yielde0
- Direction
- lowere0
- Qualifier
- PRE-only programe0
- Comparator
- no-cover crop CT systeme0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Under a PRE-only program, all cover crop systems had lower yield compared to the no-cover crop CT system”
t0“Soybean”
Claim · model-written summary
With POST weed control, cover crops except Italian ryegrass did not reduce soybean yield relative to conventional tillage.
- Taxon
- soybeanGlycine maxe0
- Treatment
- all cover cropse0
- Outcome
- soybean yieldse0
- Direction
- not differente0
- Qualifier
- except Italian ryegrasse0
- Comparator
- no-cover crop CT plotse0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“When late-emerged weeds were controlled with POST applications (POST-only or PRE POST programs), all cover crops, except Italian ryegrass, had no detrimental effect on soybean yields, which were not different from no-cover crop CT plots”
Claim · model-written summary
Cover crops had high input costs from seed, planting and desiccation.
Verbatim
e0“In cover crops, input costs were high due to additional cost of seeds, planting, and desiccation”
Claim · model-written summary
No-cover no-tillage had the highest net return of $105/ha.
- Taxon
- soybeanGlycine maxt0
- Treatment
- no-cover crop NTe0
- Outcome
- Net returne0
- Direction
- higheste0
- Value
- $105/hae0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Net return was highest in no-cover crop NT ($105/ha) followed by no-cover crop CT ($76/ha) system”
t0“Soybean”
Claim · model-written summary
No-cover conventional tillage returned $76/ha.
- Taxon
- soybeanGlycine maxt0
- Treatment
- no-cover crop CTe0
- Outcome
- Net returne0
- Value
- $76/hae0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Net return was highest in no-cover crop NT ($105/ha) followed by no-cover crop CT ($76/ha) system”
t0“Soybean”
Claim · model-written summary
All cover crops had negative net returns.
Verbatim
e0“Net returns were negative for all cover crops”
Claim · model-written summary
Crimson clover produced a $62/ha loss.
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“losses were highest in crimson clover (−$62/ha) and subterranean clover (−$161/ha)”
t0“Soybean”
Claim · model-written summary
Subterranean clover produced a $161/ha loss.
- Taxon
- soybeanGlycine maxt0
- Treatment
- subterranean clovere0
- Outcome
- lossese0
- Direction
- higheste0
- Value
- −$161/hae0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“losses were highest in crimson clover (−$62/ha) and subterranean clover (−$161/ha)”
t0“Soybean”
The same questions in other papers
Triticum aestivum · weed · Glycine max (soybean)Positive and negative results
2 papers in the same direction as this paper · 1 in the opposite direction
- positive
- no effect
- no effect
cover crop · organism · Glycine max (soybean)Positive and negative results
6 papers in the same direction as this paper · 4 in the opposite direction
- positive
- no effect
- negative
7 papers more in this group
See all 11 papers →cover crop · yield · Glycine max (soybean)Positive and negative results
67 papers in the same direction as this paper · 33 in the opposite direction
- positive
- positive
- no effect
97 papers more in this group
See all 101 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.