Abstract
Abstract Onion (Allium cepa cv. Spanish Sweet Utah), lettuce (Lactuca sativa cv. Black Seeded Simpson), snapdragon (Antirrhinum majus cv. Sonnet Yellow), and turfgrass (Festuca arundinacea cv. Marathon) were grown twice annually (spring and fall) on a San Emigdio sandy loam (coarse‐loamy, mixed calcareous thermic, Typic Xerorthents) soil for two years that was treated with a cumulative total of 0, 37, and 74 MT/ha of sewage sludge compost from San Diego. The soil received two compost treatments each year and crops were planted within a week of compost incorporation. Crop growth was monitored and the results of the fourth or final planting are described here. Seedlings of onion, snapdragon and lettuce transplanted to compost treated plots displayed more vigorous establishment than those in the control plots. Compost treatments produced higher yields of onion, turf and lettuce. Snapdragon yield was not affected by compost treatment. Soil analysis of compost treated plots revealed lowered pH and increased levels of organic matter, primary nutrients, soluble salts and heavy metals. A concurrent greenhouse study demonstrated that the presence of chipped Eucalyptus tree trimmings (60% by volume) in the sewage sludge compost did not inhibit the growth of the test crops.
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Claims 11
Claim · model-written summary
Compost improved establishment of onion seedlings relative to controls.
- Taxon
- onion
Allium cepae0 - Treatment
- compost treated plotse0
- Outcome
- establishmente0
- Direction
- more vigorouse0
- Comparator
- control plotse0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.

Verbatim
e0“Seedlings of onion, snapdragon and lettuce transplanted to compost treated plots displayed more vigorous establishment than those in the control plots.”
Claim · model-written summary
Compost improved establishment of snapdragon seedlings relative to controls.
- Taxon
- snapdragon
Antirrhinum majuse0
- Treatment
- compost treated plotse0
- Outcome
- establishmente0
- Direction
- more vigorouse0
- Comparator
- control plotse0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Seedlings of onion, snapdragon and lettuce transplanted to compost treated plots displayed more vigorous establishment than those in the control plots.”
Claim · model-written summary
Compost improved establishment of lettuce seedlings relative to controls.
- Taxon
- lettuce
Lactuca sativae0 - Treatment
- compost treated plotse0
- Outcome
- establishmente0
- Direction
- more vigorouse0
- Comparator
- control plotse0
Organisms pictured · Representative pictures of the matched species, not figures from the paper.

Verbatim
e0“Seedlings of onion, snapdragon and lettuce transplanted to compost treated plots displayed more vigorous establishment than those in the control plots.”
Claim · model-written summary
Compost increased onion yield.
- Taxon
- onion
Allium cepae0 - Treatment
- Compost treatmentse0
- Outcome
- yieldse0
- Direction
- highere0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.

Verbatim
e0“Compost treatments produced higher yields of onion, turf and lettuce.”
Claim · model-written summary
Compost increased turf yield.
Not reportedComparator
Verbatim
e0“Compost treatments produced higher yields of onion, turf and lettuce.”
Claim · model-written summary
Compost increased lettuce yield.
- Taxon
- lettuce
Lactuca sativae0 - Treatment
- Compost treatmentse0
- Outcome
- yieldse0
- Direction
- highere0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.

Verbatim
e0“Compost treatments produced higher yields of onion, turf and lettuce.”
Claim · model-written summary
Compost did not affect snapdragon yield.
- Taxon
- Snapdragon
Antirrhinum majuse0
- Treatment
- compost treatmente0
- Outcome
- yielde0
- Direction
- not affectede0
Not reportedComparator
Organisms pictured · Representative pictures of the matched species, not figures from the paper.
Verbatim
e0“Snapdragon yield was not affected by compost treatment.”
Claim · model-written summary
Compost lowered soil pH.
Not reportedTaxonComparator
Verbatim
e0“Soil analysis of compost treated plots revealed lowered pH and increased levels of organic matter, primary nutrients, soluble salts and heavy metals.”
Claim · model-written summary
Compost increased soil organic matter, primary nutrients and soluble salts.
- Treatment
- compost treated plotse0
- Outcome
- organic matter, primary nutrients, soluble saltse0
- Direction
- increasede0
Not reportedTaxonComparator
Verbatim
e0“Soil analysis of compost treated plots revealed lowered pH and increased levels of organic matter, primary nutrients, soluble salts and heavy metals.”
Claim · model-written summary
Compost increased soil heavy metals.
Not reportedTaxonComparator
Verbatim
e0“Soil analysis of compost treated plots revealed lowered pH and increased levels of organic matter, primary nutrients, soluble salts and heavy metals.”
Claim · model-written summary
Chipped Eucalyptus tree trimmings in compost did not inhibit test crop growth.
- Taxon
- test cropse0
- Treatment
- chipped Eucalyptus tree trimmings (60% by volume) in the sewage sludge composte0
- Outcome
- growthe0
- Direction
- did not inhibite0
Not reportedComparatorSetting
Verbatim
e0“the presence of chipped Eucalyptus tree trimmings (60% by volume) in the sewage sludge compost did not inhibit the growth of the test crops.”
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See all 530 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.