Abstract
Abstract Leaf N and soil nitrate and ammonium levels were monitored in 1986 and 1987 following N fertilization of 8–9 year old highbush blueberries. Urea was applied at 76 kg N/ha in a single application at bud break or in two applications (split) at bud break and petal fall. Controlled release fertilizers (CRF), of two different residual effects (Osmocote 3 mo., Osmocote 8 mo.) were applied at 38 kg N/ha or 76 kg N/ha at bud break. Compared to controls, N applications increased soil ammonium and nitrate levels early in the season and leaf N levels throughout the season. Urea provided a greater increase in leaf N and soil ammonium levels than CRF. Split urea applications increase leaf levels slightly over single urea treatments. Fertilizers increased soil ammonium and nitrate levels below the root zone, indicating that some leaching losses occurred.
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Claims 6
Claim · model-written summary
Nitrogen applications increased soil ammonium and nitrate early in the season.
- Taxon
- highbush blueberries
Vaccinium corymbosumt0 - Treatment
- N applicationse0
- Outcome
- soil ammonium and nitrate levelse0
- Direction
- increasede0
- Qualifier
- early in the seasone0
- Comparator
- controlse0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Compared to controls, N applications increased soil ammonium and nitrate levels early in the season”
t0“highbush blueberries”
Claim · model-written summary
Nitrogen applications increased leaf nitrogen throughout the season.
- Taxon
- highbush blueberriesVaccinium corymbosumt0
- Treatment
- N applicationse0
- Outcome
- leaf N levelse0
- Direction
- increasede0
- Qualifier
- throughout the seasone0
- Comparator
- controlse0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Compared to controls, N applications increased soil ammonium and nitrate levels early in the season and leaf N levels throughout the season”
t0“highbush blueberries”
Claim · model-written summary
Urea increased leaf nitrogen more than controlled release fertilizer.
- Taxon
- highbush blueberriesVaccinium corymbosumt0
- Treatment
- Ureae0
- Outcome
- leaf Ne0
- Direction
- greater increasee0
- Comparator
- CRFe0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Urea provided a greater increase in leaf N and soil ammonium levels than CRF”
t0“highbush blueberries”
Claim · model-written summary
Urea increased soil ammonium more than controlled release fertilizer.
- Taxon
- highbush blueberriesVaccinium corymbosumt0
- Treatment
- Ureae0
- Outcome
- soil ammonium levelse0
- Direction
- greater increasee0
- Comparator
- CRFe0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Urea provided a greater increase in leaf N and soil ammonium levels than CRF”
t0“highbush blueberries”
Claim · model-written summary
Split urea applications slightly increased leaf levels relative to single urea treatments.
- Taxon
- highbush blueberriesVaccinium corymbosumt0
- Treatment
- Split urea applicationse0
- Outcome
- leaf levelse0
- Direction
- increasee0
- Qualifier
- slightlye0
- Comparator
- single urea treatmentse0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Split urea applications increase leaf levels slightly over single urea treatments”
t0“highbush blueberries”
Claim · model-written summary
Fertilizers increased soil ammonium and nitrate below the root zone, indicating leaching.
- Taxon
- highbush blueberriesVaccinium corymbosumt0
- Treatment
- Fertilizerse0
- Outcome
- soil ammonium and nitrate levelse0
- Direction
- increasede0
- Qualifier
- below the root zonee0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Fertilizers increased soil ammonium and nitrate levels below the root zone, indicating that some leaching losses occurred”
t0“highbush blueberries”
The same questions in other papers
nitrogen · nutrient: content · Vaccinium corymbosum (highbush blueberry)Positive and negative results
3 papers in the same direction as this paper · 2 in the opposite direction
- no effect
- negative
- positive
2 papers more in this group
See all 6 papers →fertilization · nutrient: content · Vaccinium corymbosum (highbush blueberry)Positive and negative results
4 papers in the same direction as this paper · 8 in the opposite direction
- no effect
- positive
- positive
9 papers more in this group
See all 13 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.