Abstract
The use of freshly harvested and processed pine trees as a container substrate for greenhouse and nursery crop production is a relatively new concept, and fundamental knowledge of the construction of a pine tree substrate (PTS) for optimal physical properties is insufficient. Therefore, this research was conducted to determine the influence of mixing PTSs produced with different wood particle sizes and adding other amendments to PTS on substrate physical properties and plant growth compared with traditional substrates. Coarse pine wood chips produced from 15-year-old loblolly pine trees ( Pinus taeda L.) were ground in a hammermill fitted with either a 4.76-mm screen or with no screen (PTS-NS) allowing a fine and a coarse particle PTS to be produced. Increasing proportions of the finer (4.76-mm) PTS to the coarser PTS (PTS-NS) resulted in increased container capacity (CC) and shoot growth of ‘Inca Gold’ marigold ( Tagetes erecta L.). In another study, PTSs were manufactured in a hammermill fitted with different screen sizes: 4.76, 6.35, 9.54, or 15.8 mm as well as PTS-NS. After being hammermilled, each of the five PTSs was then amended (by mixing) with 10% sand (PTS-S), 25% peatmoss (PTS-PM), or left unamended. Pine tree substrates were also produced by adding 25% aged pine bark (PB) to pine wood chips before being ground in a hammermill with each of the five screen sizes mentioned (PTS-HPB). These five substrates were used unamended as well as amended with 10% sand after grinding (PTS-HPBS). Control treatments included peat-lite (PL) and 100% aged PB for a total of 27 substrates evaluated in this study. Container capacity and marigold growth increased as screen size decreased and with the additions of peatmoss (PTS-PM) or hammering with PB (PTS-HPB) to PTS. Container capacity for all substrates amended with peatmoss or PB was within the recommended range of 45% to 65% for container substrates, but only with the more finely ground PTS-4.76-mm resulted in marigold growth comparable to PL and PB. However, when the PTS-NS was amended by mixing in 25% peat or hammering with 25% PB, growth of marigold was equal to plants grown in PL or PB. In a third study, hammering PTS-NS with 25% PB followed by the addition of 10% sand increased dry weight of both azalea ( Rhododendron × hybrida ‘Girard Pleasant White’) and spirea ( Spiraea nipponica Maxim. ‘Snowmound’) resulting in growth equal to plants grown in 100% PB. This work shows that amending coarsely ground PTS with finer particle PTS or with other materials (peatmoss, aged PB, or sand) can result in a substrate with comparable physical properties such as CC and plant growth compared with 100% PL or PB.
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Claims 10
Claim · model-written summary
Finer pine substrate increased container capacity and marigold shoot growth.
Verbatim
e0“Increasing proportions of the finer (4.76-mm) PTS to the coarser PTS (PTS-NS) resulted in increased container capacity (CC) and shoot growth of ‘Inca Gold’ marigold ( Tagetes erecta L.).”
Claim · model-written summary
Smaller screen size increased container capacity and marigold growth.
- Taxon
- marigolde0
- Treatment
- screen size decreasede0
- Outcome
- Container capacity and marigold growthe0
- Direction
- increasede0
Not reportedComparator
Verbatim
e0“Container capacity and marigold growth increased as screen size decreased”
Claim · model-written summary
Peatmoss addition increased container capacity and marigold growth.
- Taxon
- marigolde0
- Treatment
- additions of peatmoss (PTS-PM)e0
- Outcome
- Container capacity and marigold growthe0
- Direction
- increasede0
Not reportedComparator
Verbatim
e0“Container capacity and marigold growth increased as screen size decreased and with the additions of peatmoss (PTS-PM)”
Claim · model-written summary
Pine bark hammering increased container capacity and marigold growth.
- Taxon
- marigolde0
- Treatment
- hammering with PB (PTS-HPB)e0
- Outcome
- Container capacity and marigold growthe0
- Direction
- increasede0
Not reportedComparator
Verbatim
e0“Container capacity and marigold growth increased as screen size decreased and with the additions of peatmoss (PTS-PM) or hammering with PB (PTS-HPB) to PTS.”
Claim · model-written summary
Peatmoss or bark amended substrates had recommended container capacity.
Not reportedTaxon
Verbatim
e0“Container capacity for all substrates amended with peatmoss or PB was within the recommended range of 45% to 65% for container substrates”
Claim · model-written summary
Finely ground PTS-4.76-mm matched peat-lite and bark for marigold growth.
Verbatim
e0“only with the more finely ground PTS-4.76-mm resulted in marigold growth comparable to PL and PB”
Claim · model-written summary
Peat amendment of coarse PTS yielded marigold growth equal to controls.
Verbatim
e0“when the PTS-NS was amended by mixing in 25% peat or hammering with 25% PB, growth of marigold was equal to plants grown in PL or PB”
Claim · model-written summary
Bark amendment of coarse PTS yielded marigold growth equal to controls.
Verbatim
e0“when the PTS-NS was amended by mixing in 25% peat or hammering with 25% PB, growth of marigold was equal to plants grown in PL or PB”
Claim · model-written summary
Bark and sand amended PTS increased azalea dry weight to bark control growth.
Verbatim
e0“hammering PTS-NS with 25% PB followed by the addition of 10% sand increased dry weight of both azalea ( Rhododendron × hybrida ‘Girard Pleasant White’) and spirea ( Spiraea nipponica Maxim. ‘Snowmound’) resulting in growth equal to plants grown in 100% PB”
Claim · model-written summary
Bark and sand amended PTS increased spirea dry weight to bark control growth.
Verbatim
e0“hammering PTS-NS with 25% PB followed by the addition of 10% sand increased dry weight of both azalea ( Rhododendron × hybrida ‘Girard Pleasant White’) and spirea ( Spiraea nipponica Maxim. ‘Snowmound’) resulting in growth equal to plants grown in 100% PB”
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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.