Effect of Fertilizer Rate on Growth of Azalea and Holly in Pine Bark and Pine Tree Substrates

Recent interest in the use of wood substrates in horticulture crop production has justified the need for determining fertilizer requirements in these substrates compared with traditional pine bark (PB) and peatmoss substrates. The objective was to determine the response of japanese holly (Ilex crenata Thunb. ‘Compacta’) and azalea (Rhododendron obtusum Planck. ‘Delaware Valley’) grown in a pine tree substrate (PTS) (trade name WoodGro™) or milled PB to fertilizer rate. Pine tree substrate is produced from freshly harvested loblolly pine trees (Pinus taeda L.) that are delimbed, chipped, and ground in a hammer mill to a desired particle size. Japanese holly plants were grown in 2.8-L containers in the fall of 2005 and again in the spring of 2007 with the addition of azalea. Plants grown in PTS or PB were fertilized by incorporating Osmocote Plus fertilizer (15N–3.9P–10K) at rates of 3.5, 5.9, 8.3 or 10.6 kg·m−3 for japanese holly and 1.2, 3.5, 5.9, or 8.3 kg·m−3 for azalea. After 3 months, shoot dry weights were determined for japanese holly and azalea. Japanese holly root dry weights were determined for both experiments, and substrate CO2 efflux (μmol CO2 m−2·s−1) was measured on the treatments at the end of the experiment using a LI-6400 soil CO2 flux chamber. In 2005, japanese holly shoot dry weights of PTS-grown plants were comparable to plants grown in PB at the 8.3 kg·m−3 fertility rate, and shoot dry weights of PTS-grown plants were higher than PB at the 10.6 kg·m−3 rate. In 2007, japanese holly and azalea shoot dry weights of PTS-grown plants were comparable to PB plants at the 5.9 kg·m−3 fertilizer rate. Both japanese holly and azalea achieved shoot growth in PTS comparable to shoot growth in PB with ≈2.4 kg·m−3 additional fertilizer for PTS. Substrate CO2 efflux rates were higher in PTS compared with PB indicating higher microbial activity, thereby increasing the potential for nutrient immobilization in PTS.

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WholeTree Substrates Derived from Three Species of Pine in Production of Annual Vinca

HortTechnology ◽

10.21273/horttech.18.1.13 ◽

2008 ◽

Vol 18 (1) ◽

pp. 13-17 ◽

Cited By ~ 16

Author(s):

Glenn B. Fain ◽

Charles H. Gilliam ◽

Jeff L. Sibley ◽

Cheryl R. Boyer

Keyword(s):

Loblolly Pine ◽

Longleaf Pine ◽

Pinus Palustris ◽

Ground Level ◽

Pinus Elliottii ◽

Slash Pine ◽

Pine Bark ◽

Hammer Mill ◽

Horticultural Crops ◽

Pine Trees

The objective of this study was to evaluate the potential for use of container substrates composed of processed whole pine trees (WholeTree). Three species [loblolly pine (Pinus taeda), slash pine (Pinus elliottii), and longleaf pine (Pinus palustris)] of 8- to 10-year-old pine trees were harvested at ground level and the entire tree was chipped with a tree chipper. Chips from each tree species were processed with a hammer mill to pass through a 0.374-inch screen. On 29 June 2005 1-gal containers were filled with substrates, placed into full sun under overhead irrigation, and planted with a single liner (63.4 cm3) of ‘Little Blanche’ annual vinca (Catharanthus roseus). The test was repeated on 27 Aug. 2005 with ‘Raspberry Red Cooler’ annual vinca. Pine bark substrate had about 50% less air space and 32% greater water holding capacity than the other substrates. At 54 days after potting (DAP), shoot dry weights were 15% greater for plants grown in 100% pine bark substrate compared with plants grown in the three WholeTree substrates. However, there were no differences in plant growth indices for any substrate at 54 DAP. Plant tissue macronutrient content was similar among all substrates. Tissue micronutrient content was similar and within sufficiency ranges with the exception of manganese. Manganese was highest for substrates made from slash pine and loblolly pine. Root growth was similar among all treatments. Results from the second study were similar. Based on these results, WholeTree substrates derived from loblolly pine, slash pine, or longleaf pine have potential as an alternative, sustainable source for producing short-term horticultural crops.

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Growth of Chrysanthemum in a Pine Tree Substrate Requires Additional Fertilizer

HortTechnology ◽

10.21273/horttech.18.1.111 ◽

2008 ◽

Vol 18 (1) ◽

pp. 111-115 ◽

Cited By ~ 8

Author(s):

Robert D. Wright ◽

Brian E. Jackson ◽

Jake F. Browder ◽

Joyce G. Latimer

Keyword(s):

Pinus Taeda ◽

Loblolly Pine ◽

Baton Rouge ◽

Exchange Capacity ◽

Hammer Mill ◽

Greenhouse Crops ◽

Nutrient Levels ◽

Pine Tree ◽

Pine Trees ◽

Soluble Fertilizer

A pine tree substrate (PTS), produced by grinding loblolly pine trees (Pinus taeda), offers potential as a viable container substrate for greenhouse crops, but a better understanding of the fertilizer requirements for plant growth in PTS is needed. The purpose of this research was to determine the comparative fertilizer requirements for chrysanthemum (Chrysanthemum ×grandiflora ‘Baton Rouge’) grown in PTS or a commercial peat-lite (PL) substrate. The PTS was prepared by grinding coarse (1-inch × 1-inch × 0.5-inch) pine chips from debarked loblolly pine logs in a hammer mill fitted with 3/16-inch screen. The PL substrate composed of 45% peat, 15% perlite, 15% vermiculite, and 25% bark was used for comparative purposes. Rooted chrysanthemum cuttings were potted in each of the substrates on 15 Oct. 2005 and 12 Apr. 2006 and were glasshouse grown. Plants were fertilized with varying rates of a 20N–4.4P–16.6K-soluble fertilizer ranging from 50 to 400 mg·L−1 nitrogen (N) with each irrigation. Plant dry weights and extractable substrate nutrient levels were determined. In 2005 and 2006, it required about 100 mg·L−1 N more fertilizer for PTS compared to PL to obtain comparable growth. At any particular fertilizer level, substrate electrical conductivity and nutrient levels were higher for PL compared to PTS accounting for the higher fertilizer requirements for PTS. Possible reasons for the lower substrate nutrients levels with PTS are increased nutrient leaching in PTS due to PTS being more porous and having a lower cation exchange capacity than PL, and increased microbial immobilization of N in PTS compared to PL. This research demonstrates that PTS can be used to grow a traditional greenhouse crop if attention is given to fertilizer requirements.

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PHYSICAL PROPERTIES OF MEDIA COMPOSED OF GROUND WHOLE PINE TREES AND THEIR EFFECTS ON VINCA (CATHARANTHUS ROSEUS) GROWTH

HortScience ◽

10.21273/hortsci.41.3.510b ◽

2006 ◽

Vol 41 (3) ◽

pp. 510B-510

Author(s):

Glenn B. Fain ◽

Charles H. Gilliam

Keyword(s):

Physical Properties ◽

Loblolly Pine ◽

Catharanthus Roseus ◽

Plant Tissue ◽

Pinus Palustris ◽

Growth Index ◽

Pinus Elliottii ◽

Hammer Mill ◽

Nutrient Analysis ◽

Pine Trees

The objective of this study was to evaluate the potential use of container substrates composed of whole pine trees. Three species [loblolly pine (Pinus taeda), slash pine (Pinus elliottii) and longleaf pine (Pinus palustris)] of 8–10 year old pine trees were harvested at ground level and the entire tree was chipped with a tree chipper. The chips from each tree species were then further processed with a hammer mill to pass a ½-inch screen. On 29 June 2005 these three substrates along with 100% pinebark were mixed with the addition per cubic yard of 9.49 kg·m–3 Polyon 18–6–12 (18N–2.6P–10K), 2.97 kg·m–3 dolomitic lime and 0.89 kg·m–3 Micromax. One gallon (3.8 L) containers were then filled and placed into full sun under overhead irrigation. Into these containers were planted 72 cell plugs of Catharanthus roseus`Little Blanche'. Data collected were pre-plant chemical and physical properties of substrates, as well as plant growth index (GI), plant top dry weight, root ratings, and plant tissue (leaves) nutrient analysis at 60 days after planting (DAP). The test was repeated on 27 Aug. 2005 with C. roseus Raspberry Red Cooler. Top dry weights were on average 15% greater for the 100% pinebark substrate over all others at 60 DAP. However there were non differences in plant GI for any substrate at 60 DAP. There were no differences in plant tissue macro nutrient content for any substrate. Tissue micronutrient content was similar and within ranges reported by Mills and Jones (1996, Plant Analysis Handbook II) with the exception of Manganese. Manganese was highest for slash and loblolly pine and well over reported ranges. There were no differences in root ratings. There were no differences in substrate physical properties between the three whole tree substrates. However the 100% pinebark substrate had on average 50% less air space and 25% greater water holding capacity than the other substrates. Physical properties of all substrates were within recommended ranges. Based on the results of this study substrates composed of whole pine trees have potential as an alternative sustainable source for a substrate used in producing short term nursery crops.

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WholeTree Substrate and Fertilizer Rate in Production of Greenhouse-grown Petunia (Petunia ×hybrida Vilm.) and Marigold (Tagetes patula L.)

HortScience ◽

10.21273/hortsci.43.3.700 ◽

2008 ◽

Vol 43 (3) ◽

pp. 700-705 ◽

Cited By ~ 8

Author(s):

Glenn B. Fain ◽

Charles H. Gilliam ◽

Jeff L. Sibley ◽

Cheryl R. Boyer ◽

Anthony L. Witcher

Keyword(s):

Pinus Taeda ◽

Loblolly Pine ◽

Petunia Hybrida ◽

Ground Level ◽

Dry Weight ◽

Hammer Mill ◽

Tagetes Patula ◽

Fertilizer Rate ◽

Starter Fertilizer ◽

Industry Standard

A substrate component (WholeTree) made from loblolly pine (Pinus taeda L.) was evaluated along with starter fertilizer rate in the production of greenhouse-grown petunia (Petunia ×hybrida Vilm. ‘Dreams Purple’) and marigold (Tagetes patula L. ‘Hero Spry’). Loblolly pine from a 12-year-old plantation were harvested at ground level, chipped, and further processed through a hammer mill to pass a 0.64-cm screen. The resulting WholeTree (WT) substrate was used alone or combined with 20% (WTP2) or 50% (WTP5) (by volume) Canadian sphagnum peatmoss and compared with an industry standard peat-lite (PL) mix of 8 peatmoss : 1 vermiculite : 1 perlite (by volume). Substrates were amended with 1.78 kg·m−3 dolomitic lime, 0.59 kg·m−3 gypsum [CaSO4-2(H2O)], 0.44 kg·m−3 Micromax, 1.78 kg·m−3 16N–2.6P–9.9K (3- to 4-month release), and 1.78 kg·m−3 16N–2.6P–10.8K (5- to 6-month release). A 7N–1.3P–8.3K starter fertilizer (SF) was added to each substrate at 0.0, 1.19, 2.37, or 3.56 kg·m−3. Container capacity (CC) was greatest for PL and decreased as the percentage of peatmoss in the substrate decreased with WT having 35% less CC than PL. Conversely, air space (AS) was greatest for the WT and decreased as percentage of peatmoss increased with PL containing 33% less AS than WT. In general, petunia dry weight was greatest for any substrate containing peatmoss with a SF rate of 2.37 kg·m−3 or greater. The exception was that petunia grown in WT at 3.56 kg·m−3 SF had similar dry weight as all other treatments. Marigold dry weight was similar for all substrates where at least 2.37 kg·m−3 SF was used.

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The Landscape Performance of Annual Bedding Plants Grown in Pine Tree Substrate

HortTechnology ◽

10.21273/hortsci.19.1.78 ◽

2009 ◽

Vol 19 (1) ◽

pp. 78-82 ◽

Cited By ~ 8

Author(s):

Robert D. Wright ◽

Brian E. Jackson ◽

Michael C. Barnes ◽

Jake F. Browder

Keyword(s):

Loblolly Pine ◽

Dry Weight ◽

Plant Size ◽

Growing Period ◽

Bedding Plants ◽

Pine Tree ◽

Landscape Performance ◽

Pine Trees ◽

Impatiens Walleriana ◽

Fertilizer Rates

The objective of this study was to evaluate the landscape performance of annual bedding plants grown in a ground pine tree substrate (PTS) produced from loblolly pine trees (Pinus taeda) or in ground pine bark (PB) when transplanted into the landscape and grown at three different fertilizer rates. Begonia (Begonia ×semperflorens-cultorum) ‘Cocktail Vodka’, coleus (Solenostemen scutellarioides) ‘Kingswood Torch’, impatiens (Impatiens walleriana) ‘Dazzler White’, marigold (Tagetes erecta) ‘Bonanza Yellow’, petunia (Petunia ×hybrid) ‘Wave Purple’, salvia (Salvia splendens) ‘Red Hot Sally’, and vinca (Catharanthus roseus) ‘Cooler Pink’ were evaluated in 2005, and begonia ‘Cocktail Whiskey’, marigold ‘Inca Gold’, salvia ‘Red Hot Sally’, and vinca ‘Cooler Pink’ were evaluated in 2006 and 2007. Landscape fertilizer rates were 1 lb/1000 ft2 nitrogen (N) in 2005 and 0, 1, and 2 lb/1000 ft2 N in 2006 and 2007. Visual observations throughout each year indicated that all species, whether grown in PTS or PB, had comparable foliage quality in the landscape trial beds during the growing period. With few exceptions, dry weight and plant size for all species increased with increasing fertilizer additions, regardless of the substrate in which the plants were grown. For the unfertilized treatment, when comparing plant dry weight between PB and PTS for each species and for each year (eight comparisons), PTS-grown plant dry weight was less than PB-grown plants in three out of the eight comparisons. However, there were fewer differences in plant dry weight between PTS- and PB-grown plants when fertilizer was applied (PTS-grown plants were smaller than PB-grown plants in only 2 of the 16 comparisons: four species, two fertilizer rates, and 2 years), indicating that N immobilization may be somewhat of an issue, but not to the extent expected. Therefore, the utilization of PTS as a substrate for the production of landscape annuals may be acceptable in the context of landscape performance.

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Eastern Redcedar (Juniperus virginiana) as a Substrate Component Effects Growth of Three Tree Species

Journal of Environmental Horticulture ◽

10.24266/0738-2898.30.4.189 ◽

2012 ◽

Vol 30 (4) ◽

pp. 189-194

Author(s):

Zachariah W. Starr ◽

Cheryl R. Boyer ◽

Jason J. Griffin

Keyword(s):

Great Plains ◽

Tree Species ◽

Crop Production ◽

The United States ◽

Limiting Factor ◽

Juniperus Virginiana ◽

Hammer Mill ◽

Eastern Redcedar ◽

Fertilizer Rate ◽

Fertilizer Rates

Sustainable and local alternative substrates are being explored for nursery crop production due to concern over pine bark (PB) supplies and costs. This study evaluated a tree species which is weedy in the Great Plains region of the United States, eastern redcedar, processed through a hammer mill equipped with a 19 mm (3/4 in) screen size to create six substrates consisting of 0, 5, 10, 20, 40, and 80% eastern redcedar chips (ERC) and 20% sand; the remaining volume was composed of PB. Each of these substrates were then used to grow baldcypress (Taxodium distichum), Chinese pistache (Pistacia chinensis), and silver maple (Acer saccharinum) under two fertilizer rates: either a 4.5 kg·m−3 (7.5 lbs·yd−3) low fertilizer rate or a 8.9 kg·m−3 (15 lbs·yd−3) high fertilizer rate. Substrates composed of 40 and 80% ERC had reduced container capacity, resulting in less growth of all three species. Plants responded similarly to both fertilizer rates suggesting that the limiting factor to plant growth is substrate physical properties. Plants grown in 5–20% ERC were of comparable size and quality to those grown in the control substrate. Therefore, ERC can be recommended as a PB substrate supplement, but not as a full replacement at this time.

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Container Medium pH in a Pine Tree Substrate Amended with Peatmoss and Dolomitic Limestone Affects Plant Growth

HortScience ◽

10.21273/hortsci.44.7.1983 ◽

2009 ◽

Vol 44 (7) ◽

pp. 1983-1987 ◽

Cited By ~ 11

Author(s):

Brian E. Jackson ◽

Robert D. Wright ◽

Nazim Gruda

Keyword(s):

Plant Growth ◽

Pinus Taeda ◽

Loblolly Pine ◽

Rocky Mountain ◽

Dolomitic Limestone ◽

Ph Change ◽

Medium Ph ◽

Pine Tree ◽

Pine Trees ◽

Plastic Containers

This work was conducted to evaluate the effect of limestone additions to pine tree substrate (PTS) and PTS amended with peatmoss on pH and plant growth. ‘Inca Gold’ marigold (Tagetes erecta L.) and ‘Rocky Mountain White’ geranium (Pelargonium ×hortorum L.H. Bailey) were grown in three PTSs—100% PTS, PTS plus 25% peatmoss (v/v), and PTS plus 50% peatmoss (v/v)—made from freshly harvested loblolly pine trees (Pinus taeda L.) chipped and hammermilled through a 4.76-mm screen and a peatmoss/perlite (4:1 v/v; PL) control. Each substrate was amended with various rates of dolomitic limestone and used to grow marigolds in 10-cm square (l-L) plastic containers and geraniums in round 15-cm (1.25-L) plastic containers in a glasshouse. Regardless of limestone rate, pH was highest in 100% PTS and decreased with peat additions with PL having the lowest pH. As percent peat increased from 25% to 50%, more limestone was required to adjust pH to a particular level showing that PTS is more weakly buffered against pH change than peatmoss. Adding limestone did not increase the growth of marigold in 100% PTS, but additions of limestone did increase growth of marigold when grown in PTS containing peatmoss or in PL. Geranium growth was higher in PTS containing peatmoss (25% or 50%) and PL than in 100% PTS at all limestone rates. This research demonstrates that PTS produced from freshly harvested pine trees has an inherently higher pH than PL, and the additions of peatmoss to PTS require pH adjustment of the substrate for optimal plant growth.

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Stem Cutting Propagation in Whole Pine Tree Substrates

HortTechnology ◽

10.21273/horttech.24.1.30 ◽

2014 ◽

Vol 24 (1) ◽

pp. 30-37 ◽

Cited By ~ 3

Author(s):

Anthony L. Witcher ◽

Eugene K. Blythe ◽

Glenn B. Fain ◽

Kenneth J. Curry

Keyword(s):

Loblolly Pine ◽

Root Length ◽

Crop Production ◽

Fine Particles ◽

Stem Cutting ◽

Total Root Length ◽

Cutting Propagation ◽

Pine Tree ◽

Air Space ◽

Container Capacity

Wood-based substrates have been extensively evaluated for greenhouse and nursery crop production, yet these substrates have not been evaluated for propagation. The objective of this study was to evaluate processed whole loblolly pine trees (WPT) (Pinus taeda) as a rooting substrate for stem cutting propagation of a range of ornamental crops. Substrates included processed WPT, pine (Pinus sp.) bark (PB), and each mixed with equal parts (by volume) peatmoss (PM) (WPT:PM and PB:PM, respectively). Substrate physical (air space, container capacity, total porosity, bulk density, and particle size distribution) and chemical [pH and electrical conductivity (EC)] properties were determined for all substrates. Rooting percentage, total root length, total root volume, and total shoot length were evaluated for four species in 2008 and five species in 2009. Substrate air space was similar between PB and WPT in the 2008 experiment, and likewise between PB:PM and WPT:PM. In the 2009 experiment, PB and WPT had similar substrate air space. The addition of PM to PB and WPT resulted in reduced air space and increased container capacity in both experiments. The proportion of fine particles doubled for PB:PM and WPT:PM compared with PB and WPT, respectively. Substrate pH for all substrates ranged from 6.0 to 6.9 at 7 days after sticking (DAS) cuttings and 6.9 to 7.1 at 79 DAS. Substrate EC was below the acceptable range for all substrates except at 7 DAS. Rooting percentage was similar among substrates within each species in both experiments. The addition of PM resulted in significantly greater total root length for PB:PM and WPT:PM compared with PB and WPT, respectively, for five of the eight species. Shoot growth was most vigorous for PB:PM compared with the other substrates for all species. The study demonstrated a range of plant species can be propagated from stem cuttings in whole pine tree substrates alone or combined with PM.

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Changes in Chemical and Physical Properties of Pine Tree Substrate and Pine Bark During Long-term Nursery Crop Production

HortScience ◽

10.21273/hortsci.44.3.791 ◽

2009 ◽

Vol 44 (3) ◽

pp. 791-799 ◽

Cited By ~ 29

Author(s):

Brian E. Jackson ◽

Robert D. Wright ◽

John R. Seiler

Keyword(s):

Microbial Activity ◽

Crop Production ◽

Chemical Properties ◽

Pine Bark ◽

Nutrient Concentrations ◽

Substrate Solution ◽

Nutrient Immobilization ◽

Pine Tree ◽

Fertilizer Rates

The objective of this study was to evaluate a pine tree substrate (PTS) for decomposition, changes in physical and chemical properties, and substrate carbon dioxide (CO2) efflux (microbial activity) during a long-term production cycle under outdoor nursery conditions. Substrates used in this study were PTS constructed using a 4.76-mm hammer mill screen and aged pine bark (PB). Plastic nursery containers were filled with each substrate and amended with either 4.2 or 8.4 kg·m−3 Osmocote Plus fertilizer and planted with Cotoneaster horizontalis or left fallow. Substrate solution chemical properties and nutrient concentrations were determined each month during the summers of 2006 and 2007 in addition to measuring substrate CO2 efflux (μmol CO2/m−2·s−1) as an assessment of microbial activity. Substrate breakdown (decomposition) was determined with particle size analysis and physical property determination on substrates at the conclusion of the study (70 weeks). Substrate solution pH was higher in PTS than in PB at both fertilizer rates in 2006, but pH levels decreased over time and were lower in PTS at both fertilizer rates in 2007. Substrate solution electrical conductivity levels, nitrate, phosphorus, and potassium concentrations were all generally higher in PB than in PTS at both fertilizer rates through both years. Pine tree substrate decomposition was higher when plants were present in the containers [evident by an increase in fine substrate particles (less than 0.5 mm) after 70 weeks], but breakdown was equal at both fertilizer rates. Shrinkage of PTS in the presence of plants was equal to the shrinkage observed in PB with plants, but shrinkage was higher in fallow PTS containers than PTS with plants. Substrate air apace (AS) was highest in PTS and container capacity (CC) was equal in PB and PTS at potting. Substrate AS decreased and CC increased in both substrates after 70 weeks but remained in acceptable ranges for container substrates. Substrate CO2 efflux rates were higher in PTS compared with PB at both fertilizer rates indicating higher microbial activity, thereby increasing the potential for nutrient immobilization and substrate breakdown. This work provides evidence that PTS decomposition is unaffected by fertilizer rate and that substrate shrinkage in containers with plants is similar to PB after two growing seasons (70 weeks), which addresses two major concerns about the use and performance of PTS for long-term nursery crop production. This work also shows that the higher microbial activity in PTS increases the potential of microbial nutrient immobilization, which is likely the reason for the lower substrate nutrient levels reported for PTS compared with PB over 70 weeks.

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Modeling the Effect of Density on the Growth of Loblolly Pine Trees

Southern Journal of Applied Forestry ◽

10.1093/sjaf/26.3.124 ◽

2002 ◽

Vol 26 (3) ◽

pp. 124-133 ◽

Cited By ~ 27

Author(s):

Mahadev Sharma ◽

Harold E. Burkhart ◽

Ralph L. Amateis

Keyword(s):

Loblolly Pine ◽

Tree Growth ◽

Stand Development ◽

Pine Tree ◽

Crown Length ◽

Crown Width ◽

Pine Trees ◽

Response Variables

Abstract Data from a set of loblolly pine spacing trials that have reached 16 yr since establishment were used to evaluate the effect of spacing on loblolly pine tree growth and stand development. Mean responses for six variables were evaluated: height, dbh, crown ratio, crown length, crown width, and survival. All response variables were affected by density, with dbh being the most affected and height the least affected over the 16 yr period. The rectangularity, or shape, of the growing space was not a significant factor in the development of any of these response variables. Models were constructed to characterize the development of the six response variables extrapolated over typical plantation rotation lengths of loblolly pine. South. J. Appl. For. 26(3):124–133.

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