Abstract
Abstract The time of weed removal from a crop may be as important as the extent of removal. A 4‐yr field study was conducted at two locations each year to define the extent of soybean [ Glycine max (L.) Merr.] yield and population reduction occurring from the presence of natural weed populations. Soil types were Typic Ochraqualfs and Typic Albaqualfs. ‘Williams 79’ soybeans were planted at approximately 30 seeds m − 1 of row using 76‐cm spacing between rows. Grass, broadleaf, or grass plus broadleaf weeds were allowed to interfere 0, 1, 2, 3, or 4 weeks, or all season (control), prior to their removal. Weed populations in the control plots ranged from 16 to 148 plants m −2 in 1981 and increased to 104 to 1172 plants m −2 in 1984. Allowing grass, broadleaf, or grass plus broadleaf weeds to interfere with soybeans for up to 4 weeks did not reduce soybean yields under ample soil moisture conditions. However, under drought conditions or extremely high weed infestations, yield losses with 4 weeks of interference were observed. No differences were found between the competitive effects of grasses or broadleaves on soybean yield with 4 weeks or less of interference. Significant yield reduction occurred every year at both locations when grass plus broadleaf weeds interfered all season. Yield reductions from all‐season grass‐only or broadleaf‐only weed interference occurred most years, but were dependent on location, weed density, and environmental conditions. Soybean populations were reduced where weeds were most dense and were associated with yield decreases.
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 10
Claim · model-written summary
Up to four weeks of grass weed interference did not reduce soybean yield with ample moisture.
- Taxon
- soybeans
Glycine maxe0 - Treatment
- grasse0
- Interactor
- grasse0weed
- Outcome
- soybean yieldse0
- Direction
- did not reducee0
- Qualifier
- ample soil moisture conditionse0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Allowing grass, broadleaf, or grass plus broadleaf weeds to interfere with soybeans for up to 4 weeks did not reduce soybean yields under ample soil moisture conditions”
Claim · model-written summary
Up to four weeks of broadleaf weed interference did not reduce soybean yield with ample moisture.
- Taxon
- soybeansGlycine maxe0
- Treatment
- broadleafe0
- Interactor
- broadleafe0weed
- Outcome
- soybean yieldse0
- Direction
- did not reducee0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Allowing grass, broadleaf, or grass plus broadleaf weeds to interfere with soybeans for up to 4 weeks did not reduce soybean yields under ample soil moisture conditions”
Claim · model-written summary
Up to four weeks of mixed grass and broadleaf weeds did not reduce soybean yield with ample moisture.
- Taxon
- soybeansGlycine maxe0
- Treatment
- grass plus broadleaf weedse0
- Interactor
- grass plus broadleaf weedse0weed
- Outcome
- soybean yieldse0
- Direction
- did not reducee0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Allowing grass, broadleaf, or grass plus broadleaf weeds to interfere with soybeans for up to 4 weeks did not reduce soybean yields under ample soil moisture conditions”
Claim · model-written summary
Four weeks of weed interference caused yield losses under drought or extremely high weed infestation.
- Taxon
- soybeanGlycine maxt0
- Treatment
- 4 weeks of interferencee0
- Interactor
- weede0weed
- Outcome
- yield lossese0
- Direction
- lossese0
- Qualifier
- under drought conditions or extremely high weed infestationse0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“under drought conditions or extremely high weed infestations, yield losses with 4 weeks of interference were observed”
t0“Soybean”
Claim · model-written summary
Grasses and broadleaves had similar competitive effects on soybean yield through four weeks.
- Taxon
- soybeanGlycine maxe0
- Interactor
- grasses or broadleavese0weed
- Outcome
- competitive effects of grasses or broadleaves on soybean yielde0
- Direction
- No differencese0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“No differences were found between the competitive effects of grasses or broadleaves on soybean yield with 4 weeks or less of interference”
Claim · model-written summary
All season mixed grass and broadleaf weeds significantly reduced soybean yield every year at both locations.
- Taxon
- soybeanGlycine maxt0
- Treatment
- grass plus broadleaf weeds interfered all seasone0
- Interactor
- grass plus broadleaf weedse0weed
- Outcome
- yielde0
- Direction
- reductione0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Significant yield reduction occurred every year at both locations when grass plus broadleaf weeds interfered all season”
t0“Soybean”
Claim · model-written summary
All season grass only weed interference reduced soybean yield in most years depending on context.
- Taxon
- soybeanGlycine maxt0
- Treatment
- all‐season grass‐onlye0
- Interactor
- grasse0weed
- Outcome
- Yielde0
- Direction
- reductionse0
- Qualifier
- dependent on location, weed density, and environmental conditionse0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Yield reductions from all‐season grass‐only or broadleaf‐only weed interference occurred most years, but were dependent on location, weed density, and environmental conditions”
t0“Soybean”
Claim · model-written summary
All season broadleaf only weed interference reduced soybean yield in most years depending on context.
- Taxon
- soybeanGlycine maxt0
- Treatment
- broadleaf‐only weed interferencee0
- Interactor
- broadleafe0weed
- Outcome
- Yielde0
- Direction
- reductionse0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Yield reductions from all‐season grass‐only or broadleaf‐only weed interference occurred most years, but were dependent on location, weed density, and environmental conditions”
t0“Soybean”
Claim · model-written summary
Dense weeds were associated with reduced soybean populations and lower yield.
- Taxon
- SoybeanGlycine maxe0
- Interactor
- weedse0weed
- Outcome
- Soybean populationse0
- Direction
- reducede0
- Qualifier
- where weeds were most densee0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Soybean populations were reduced where weeds were most dense and were associated with yield decreases”
Claim · model-written summary
Reduced soybean populations were associated with yield decreases.
- Taxon
- SoybeanGlycine maxe0
- Organ / stage
- Soybean populationse0
- Outcome
- yield decreasese0
- Direction
- decreasese0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Soybean populations were reduced where weeds were most dense and were associated with yield decreases”
The same questions in other papers
competition · yield · Glycine max (soybean)Results differ
42 papers in the same direction as this paper · 4 in the opposite direction
- negative
- positive
- positive
43 papers more in this group
See all 47 papers →climate site · yield · Glycine max (soybean)Results differ
36 papers in the same direction as this paper · 36 in the opposite direction
- negative
- positive
- positive
69 papers more in this group
See all 73 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.