Abstract
Abstract Field studies on a Webster loam (pH 6.8) compared ammonium nitrate N to urea N for corn ( Zea mays L.). The comparison included N removal, grain yield, use as an annual fall plowdown and late June sidedressing, and use on fall‐plowed and spring surfaces. Rates of N broadcast were 45, 90, and 180 kg/ha. Starter fertilizer on all treatments supplied an additional 16 kg N, 21 kg of P, and 20 kg of K/ha (1975 lbs. of 8‐24‐12/acre). The two N sources produced equivalent average yield increases in seven of the eight comparisons, but sidedressed urea N was significantly superior to the NH 4 NO 3 when both were broadcast at the 90 kg rate. Both N sources broadcast on fall plowing were equally effective to similar treatments plowed down. Increasing N application rates significantly increased corn production and N removal, but only the highest N application rate (196 kg N/ha annually) materially increased NO 3 ‐N concentrations in the soil. None of the N treatments increased soil NO 3 ‐N concentrations beyond the 2‐m depth, and it is assumed that excess NO 3 ‐N to this soil depth was largely removed in the tile drainage waters.
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Claims 7
Claim · model-written summary
The two N sources, ammonium nitrate and urea, produced equivalent average yield increases in corn in seven of the eight comparisons.
- Taxon
- corn
Zea mays subsp. mayse0 - Treatment
- ammonium nitrate Ne0
- Outcome
- average yield increasese1
- Direction
- equivalente1
- Value
- seven of the eight comparisonse1
- Comparator
- urea Ne0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“ammonium nitrate N to urea N for corn ( Zea mays L.)”
e1“The two N sources produced equivalent average yield increases in seven of the eight comparisons”
Claim · model-written summary
Sidedressed urea N was significantly superior to NH4NO3 when both were broadcast at the 90 kg rate.
- Taxon
- cornZea mays subsp. mayse0
- Treatment
- sidedressed urea Ne1
- Outcome
- superiore1
- Direction
- superiore1
- Qualifier
- broadcast at the 90 kg ratee1
- Comparator
- NH 4 NO 3e1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“ammonium nitrate N to urea N for corn ( Zea mays L.)”
e1“sidedressed urea N was significantly superior to the NH 4 NO 3 when both were broadcast at the 90 kg rate”
Claim · model-written summary
Both N sources broadcast on fall plowing were equally effective as similar treatments plowed down.
- Taxon
- cornZea mays subsp. mayse0
- Treatment
- N sources broadcast on fall plowinge1
- Outcome
- equally effectivee1
- Direction
- equally effectivee1
- Comparator
- similar treatments plowed downe1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“ammonium nitrate N to urea N for corn ( Zea mays L.)”
e1“Both N sources broadcast on fall plowing were equally effective to similar treatments plowed down”
Claim · model-written summary
Increasing N application rates significantly increased corn production and N removal.
- Taxon
- cornZea mays subsp. mayse1
- Treatment
- Increasing N application ratese1
- Outcome
- corn production and N removale1
- Direction
- increasede1
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e1“Increasing N application rates significantly increased corn production and N removal”
Claim · model-written summary
Only the highest N application rate (196 kg N/ha annually) materially increased soil NO3-N concentrations.
- Taxon
- cornZea mays subsp. mayse0
- Treatment
- the highest N application rate (196 kg N/ha annually)e1
- Outcome
- NO 3 ‐N concentrations in the soile1
- Direction
- increasede1
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“ammonium nitrate N to urea N for corn ( Zea mays L.)”
e1“only the highest N application rate (196 kg N/ha annually) materially increased NO 3 ‐N concentrations in the soil”
Claim · model-written summary
None of the N treatments increased soil NO3-N concentrations beyond the 2-m depth.
- Taxon
- cornZea mays subsp. mayse0
- Treatment
- N treatmentse1
- Outcome
- soil NO 3 ‐N concentrations beyond the 2‐m depthe1
- Direction
- no_changeinferrede1
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“ammonium nitrate N to urea N for corn ( Zea mays L.)”
e1“None of the N treatments increased soil NO 3 ‐N concentrations beyond the 2‐m depth”
Claim · model-written summary
The authors assume that excess NO3-N to the 2-m soil depth was largely removed in tile drainage waters.
- Taxon
- cornZea mays subsp. mayse0
- Outcome
- excess NO 3 ‐N to this soil depth was largely removede1
- Qualifier
- tile drainage waterse1
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“ammonium nitrate N to urea N for corn ( Zea mays L.)”
e1“it is assumed that excess NO 3 ‐N to this soil depth was largely removed in the tile drainage waters”
The same questions in other papers
ammonium nitrate · yield · Zea mays (maize)Positive and negative results
2 papers in the same direction as this paper · 20 reporting no difference from an alternative
- positive
- positive
- positive
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See all 23 papers →nitrogen · yield · Zea mays (maize)Positive and negative results
1,905 papers in the same direction as this paper · 234 in the opposite direction · 45 reporting no difference from an alternative
- positive
- positive
- negative
2,181 papers more in this group
See all 2,185 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.