bluuebunny/crossref_metadata_2025 huggingface dataset:
Styrene-Lined and Copper-Coated Containers Affect Production of Cornus florida
Authors: Brass Thomas J. , Keever Gary J. , Gilliam Charles H. , Eakes D. Joseph
Published: August 2020

Response of dogwood cultivars (Cornus florida ‘Barton's White’ and ‘Weaver's White’) to styrene lining and copper hydroxide coating of 10.3 liter (#3) black plastic containers was evaluated in 1993 and 1994. After the first growing season, dogwoods were either left in their original containers or repotted into untreated 23.3 liter (#7) containers. Copper hydroxide reduced root circling of both cultivars in containers; however, root dry weight of plants grown in copper-treated containers was reduced during the first season. Copper-treated containers resulted in less growth in height when plants were left in their original container during the second growing season and less trunk diameter growth of plants repotted into 23.3 liter (#7) containers. In the absence of copper, more surface root coverage and less surface root dieback occurred with plants grown in styrene-lined containers. Both cultivars grown the second season in their original styrene-lined containers had greater height increase than those in unlined containers. After being repotted into 23.3 liter (#7) containers, both cultivars originally grown in styrene-lined containers had greater trunk diameter growth than those in unlined containers.
Production of Shoots from Dormant Species of Acer as Influenced by Length and Caliper of Stem Sections
Authors: Henry Paul H. , Preece John E.
Published: August 2020

Stem sections removed from selected, dormant species of Acer L. (maples) were forced to produce softwood shoots under greenhouse conditions. Species and clones varied widely in the percentage of stem sections forming shoots, and in the number of shoots that were generated per section. Both length and diameter of sections influenced the number of shoots that were generated. With respect to length, it was best to use stem sections of 30 to 40 cm (11.8 to 15.7 in) since longer sections failed to produce additional shoots and occupied considerably more production space. Effect of increased stem diameter varied across species. For A. rubrum, the number of shoots produced was greatest on ‘large’ diameter (5.2 to 7.6 cm; 2.0 to 3.0 in) stem sections; shoot production was greatest on ‘medium’ diameter (3.3 to 5.1 cm; 1.3 to 2.0 in) stem sections of A. palmatum. Data indicate that an optimum diameter will have to be determined for each species that is propagated when using this method.
Humate-Based Biostimulants Do Not Consistently Increase Growth of Container-Grown Turkish Hazelnut
Authors: Kelting Matt , Harris J. Roger , Fanelli Jody , Appleton Bonnie , Niemiera Alex
Published: August 2020

Humate-based products have been aggressively marketed to nursery producers as biostimulants which increase plant growth. Reports of their effect on container-grown trees in organic substrate are few. We tested four distinct types of biostimulants on top and root growth of Turkish hazelnut (Corylus colurna L.), grown in containers with pine-bark substrate. Treatments included: 1) an untreated control; 2) humate, applied as a dry topdress; 3) humate, formulated as a wettable powder and applied as a substrate drench; 4) humate, applied as a pre-plant root soak; 5) humate, to which various purported root growth-promoting additives had been added, also applied as a root soak. All treatments were tested within low, medium, and high fertilizer application regimes. No treatment increased top growth compared to untreated trees, and the root-soak treatments had the lowest top growth. At high and low fertilizer application rates, root length was similar for all treatments except for root-soak treatments, which had lower root lengths. At the medium fertilizer rate, root length was greatest for trees treated with granular humate applied as a dry topdressing and lowest for trees treated with root soaks.
Effect of Split Fertilizer Application and Irrigation Volume on Nitrate-Nitrogen Concentration in Container Growing Area Soil
Authors: Colangelo David J. , Brand Mark H.
Published: August 2020

Outdoor-grown, containerized, Aronia melanocarpa (Michx.) Ell. and Rhododendron ‘Roseum Elegans’ were grown atop soil-filled boxes that had been recessed into a grassed field in separate studies. Aronia were fertilized with either a single application of controlled-release fertilizer (CRF) or a split application of CRF separated by 36 days. Rhododendron were supplied a single application of CRF and either a standard or excessive irrigation volume on each irrigation day. Soil samples were taken in 30 cm (12 in) layers to a depth of 90 cm (36 in) beneath containers at 14-day intervals and soil NO3-N concentrations were determined. Accumulation of NO3-N was immediate in the 0—30 cm (0–12 in) layer for both species with accumulation of NO3-N in the deeper soil layers occurring later. Split application of a CRF was somewhat effective at reducing NO3-N accumulation at specific times and in specific soil layers, but reductions were not as substantial as studies on NO3-N concentrations in leachate have indicated. The large irrigation volumes used in the irrigation volume study resulted in NO3-N moving rapidly through the soil profile beneath containers.
Preference of Twolined Spittlebug for Ilex Species, Hybrids and Cultivars
Authors: Braman S. Kristine , Ruter John M.
Published: August 2020

Preference of twolined spittlebug, Prosapia bicincta (Say), for holly species and cultivars was evaluated in the laboratory using detached leaf assays. Field evaluations of spittlebug preference confirmed the high level of susceptibility of holly taxa with Ilex cassine L. or I. opaca Ait. parentage. Taxa observed in the field were rated as highly preferred (10 taxa), moderately (15 taxa), slightly (49), or not preferred (63) based on number of spittlebugs found infesting plants and degree of damage apparent during the two-year study. Increased production and use of pest-resistant plant material reduces the need for pesticide use and provides a good foundation for integrated pest management efforts.
Effects of Primo on Selected Bedding and Woody Landscape Plants
Authors: Keever Gary J. , Olive John W.
Published: August 2020

Primo (cimectacarb), applied as a foliar spray, suppressed shoot growth of four of six bedding plants and all four woody landscape species tested. However, phytotoxic symptoms occurred on the foliage of all bedding plants and two woody species and to flowers of three bedding plants and one woody species. Foliage and flowers of affected plants exhibited a loss of pigmentation that increased at higher rates of Primo, resulting in a bleached appearance.
An Inoculation Technique for Dogwood Anthracnose
Authors: Howard Ament Malissa , Augé Robert M. , Grand Larry F. , Windham Mark T.
Published: August 2020

Researchers have been generally unable to infect dogwood foliage (Cornus florida L.) with dogwood anthracnose (Discula destructiva Redlin) in artificial environments. We tested the influence of four factors on development of D. destructiva lesions in intact C. florida leaves wounded with a pin-prick device: (1) propagule (conidia or vegetative hyphae), (2) isolate origin (Catoctin Mountain, MD or Great Smoky Mountains National Park, TN), (3) controlled environment (growth room or air conditioned, humidified chamber in a greenhouse), and (4) period of time leaves were enclosed in humidified bags following inoculation. Of the manipulated factors, time spent in moistened bags and experimental environment were most important in determining lesion size. Lesions of similar size resulted from 0, 2 and 4 days in humidified bags, but leaves enclosed for 7 days had lesions over 5 times as large. Lesions that formed on trees in the greenhouse chamber were about 15 times larger than those in the growth room. Neither fungal propagule nor isolate origin affected lesion size. Based on this information, we have successfully infected both C. florida and Cornus kousa with D. destructiva in subsequent studies.
Early-Season Fertilization Reduces Fertilizer Use Without Reducing Plant Growth
Authors: Struve Daniel K. , Rose Mary Ann
Published: August 2020

Three experiments were conducted to determine the effect of season-long continuous fertigation (constant application of water soluble fertilizer during irrigation events) or various periods of fertigation on growth of seedlings of 17 woody plant species. For 13 of the 17 species, growth was vigorous; typically seedlings doubled in size during the 13-week experiment [from 1 m (3 ft) initial height to 1.5 or 2 m (4.5 to 6 ft) final height]. In the second and third experiments, seedlings grown under three to four weeks of fertigation (580 and 380 mg N per day, 1995 and 1996, respectively, from water soluble fertilizer) and then switched to weekly fertigation (580 and 380 mg N per week, 1995 and 1996, respectively) had similar height as seedlings receiving fertigation for 13 weeks. The three- to four-week fertigation treatment reduced nutrient application rates by 63 to 55% without reducing plant growth.
Using Horticultural Oil, Pruning, and Acephate Banding to Reduce the First Generation of Crapemyrtle Aphid
Authors: Pierce Gary L. , Baker James R. , Linker H. Michael , Warren Stuart L.
Published: August 2020

The crapemyrtle aphid, Tinocallis kahawaluokalani (Kirkaldy) is the primary insect pest of crapemyrtle, Lagerstroemia spp. Aphids excrete honeydew that serves as a source of nutrients for various sooty mold fungi. Sooty molds form a black film on the leaves that reduces plant vigor and aesthetic quality. Reduction of the first generation of crapemyrtle aphids might delay production of sooty mold, reduce mid-season pesticide applications, and decrease pesticide injury to aphid predators. Two experiments were conducted to reduce the first generation of crapemyrtle aphids without using conventional contact pesticides. Both experiments utilized Lagerstroemia indica L. ‘Acoma’ as the host plant. To create infestations on the experimental plants, adult and immature crapemyrtle aphids were captured and placed on all crapemyrtles throughout July 1994. In the first experiment, treatments included a 2% and 4% (by vol) application of horticultural oil and pruning 33% of branch terminals. Treatments were initiated prior to aphid egg eclosion in April 1995. The second experiment was intiated after eclosion when a treatment of acephate: water (3: 1 by vol) slurry was painted on crapemyrtle trunks. Horticultural oil and acephate banding treatments reduced the number of first generation aphids compared to untreated controls.
Cost Comparisons for Infield, Above Ground Container and Pot-in-Pot Production Systems
Authors: Adrian J. L. , Montgomery C. C. , Behe B. K. , Duffy P. A. , Tilt K. M.
Published: August 2020

A relatively new production system, Pot-in-Pot (PNP), offers many of the advantages of in-field (IF) and above-ground container (AGC) nursery production methods. Our objective was to compare their fixed and production costs. Hypothetical nurseries for the three production systems were synthesized to represent a 6 ha (15 A) nursery utilizing a 4 ha (10 A) production area to grow crapemyrtle (Lagerstroemia indica) over three years. Fixed costs were similar for IF and AGC systems at $350,000 with PNP system outlays $25,000 higher, largely due to socket pot cost. Total production costs for the three-year production cycle were similar for AGC and PNP at $500,000. The IF system was $50,000 less costly. Yet, on a per harvested plant basis, total cost was lowest for the PNP system ($21.52), compared to costs for the IF ($23.73) and AGC ($23.17). The PNP system had the highest total capital outlay and fixed cost, which related primarily to higher costs associated with purchasing and installing socket pots. The PNP system, however, was least costly on a per harvested plant basis due to less intensive, labor-saving cultural practices and the ability to grow larger plants quickly.
Recycled Waste Paper as a Non-chemical Alternative for Weed Control in Container Production
Authors: Smith D. R. , Gilliam C. H. , Edwards J. H. , Olive J. W. , Eakes D. J. , Williams J. D.
Published: August 2020

Studies were conducted to evaluate recycled waste paper mulch as a means of controlling weeds in the production of container-grown crops. Two forms of recycled waste paper products were evaluated—pelletized and crumbled. Both were tested at two depths, 12.5 mm (0.5 in) and 25 mm (1 in). A fabric disk and a fabric disk treated with Spin Out were also evaluated. With both the recycled waste paper mulch treatments and the fabric disk treatments, spurge seed were sown either under or on top of the treatment. Recycled waste paper pellets applied to a depth of 25 mm (1 in) suppressed spurge germination, regardless of whether spurge seed were sown on top of the mulch or under the mulch. Recycled crumble provided poor spurge control at both depths, and there was increased spurge growth when spurge were sown on top of the mulch compared to when the seed were sown under the crumble mulch. Pellets at the 25 mm (1 in) depth, provided weed control equal to that of Rout (oxyfluorfen + oryzalin) herbicide. Results from the fabric disks showed limited spurge control was obtained with any treatment. Fabric disks allowed weed growth around the container circumference and in the area where the disk fits around the plant.

Both cultivars of azaleas grown with recycled waste paper mulch were generally similar in size to non-treated control plants and Rout treated plants at 240 DAT (days after treatment). At 550 DAT plant growth was similar among all treatments except ‘Fashion’ azalea had smaller growth indices when grown with pellets compared to those grown with crumble. Container medium solution pH and electrical conductivity (soluble salts) were within the recommended range for acceptable plant growth. Research suggests that pellets applied at 25 mm (1 in) should provide effective non-chemical weed control resulting in less herbicide use and/or fewer hours of labor for weeding.
Plant Cold Acclimation, Hardiness, and Winter Injury in Response to Bare Soil and Groundcover-Based Nursery Field Management Systems
Authors: Calkins James B. , Swanson Bert T.
Published: August 2020

Effects of five nursery field management systems [cultivation, herbicide management (oxadiazon), legume companion crop (bird's-foot trefoil), winter cereal cover crop/mulch (winter rye), and mixed grass sod (red fescue/perennial ryegrass)] on cold hardiness and the incidence of winter injury were investigated over a seven-year period. Six tree species were included in the research: Fraxinus pennsylvanica ‘Marshall Seedless’, Malus ‘Red Splendor’, Gleditsia triacanthos var. inermis ‘Skyline’, Acer rubrum ‘Northwood’, Thuja occidentalis ‘Techny’, and Picea glauca var. densata. Treatment differences in fall coloration, leaf abscission, and winter injury were observed. Cold hardiness levels were determined for Acer rubrum ‘Northwood’, Malus ‘Red Splendor’, and Thuja occidentalis ‘Techny’ using controlled freezing tests. Species specific differences in cold hardiness development were observed in response to field management treatment: bare soil treatments (cultivation and herbicide management) delayed acclimation and reduced cold hardiness compared to cover crop/mulch (winter rye) and companion crop (bird's-foot trefoil and grass) treatments. Winter injury, which occurred almost exclusively in the bare soil treatments, was limited to Acer and Gleditsia. The types of injury observed included frost cracking, sunscald, branch tip dieback, dieback of large portions of the crown, and complete plant mortality. Compared to bare soil treatments, the presence of cover/companion crops and mulches in nursery field management systems increased plant cold hardiness and reduced plant losses to winter injury. Susceptibility of Gleditsia to winter injury was influenced by Nectria cinnabarina infection which was also influenced by field management treatment.
Pot-In-Pot Production and Cyclic Irrigation Influence Growth and Irrigation Efficiency of ‘Okame’ Cherries
Authors: Ruter John M.
Published: August 2020

A study was conducted with Prunus x incamp ‘Okame’ to evaluate the effects of a pot-in-pot production system (PIP) compared to a conventional above-ground system (CAG) and cyclic irrigation on plant growth and water loss. Plants were grown in #7 (26 liter) containers with a pinebark: sand (8:1 by vol) substrate. Cyclic irrigation provided the same total volume of water, but was applied one, three, or four times per day. Final plant height and stem diameter, shoot and root dry weight, total biomass, and root:shoot ratio all increased for plants grown pot-in-pot compared to above-ground. Multiple irrigation cycles increased stem diameter, shoot dry weight and total biomass compared to a single irrigation application. Multiple irrigation cycles also decreased the root:shoot ratio. Mean daily water loss (plant transpiration + evaporative loss from the substrate) was influenced by production system, irrigation, and date. Mean daily water loss was 30% higher for pot-in-pot grown plants compared to above-ground. Cyclic irrigation resulted in a two-fold decrease in average leachate volume and a 27% increase in overall irrigation application efficiency compared to a single application. Production system had no affect on leachate volume or irrigation application efficiency. Substrate pH increased when cyclic irrigation was used. Production system and irrigation had no affect on soluble salts. Nitrate-N concentrations were less in the leachate of plants grown pot-in-pot compared to above-ground.
Naturally Occurring Resistance to Powdery Mildew in Seedlings of Cornus florida
Authors: Windham Mark T. , Witte Willard T.
Published: August 2020

Two production nursery fields of flowering dogwood, Cornus florida L., seedlings with a high incidence of powdery mildew were surveyed for plants free of symptoms and signs of the disease. In greenhouse trials most of the seedlings selected in the field survey for being free of powdery mildew were found to be escapes (had no disease resistance) or to exhibit partial resistance (unacceptable low levels of resistance). In those trials, twenty seedlings, representing approximately 0.1% of the seedlings examined in the field surveys, displayed resistance to powdery mildew similar to that of C. florida ‘Cherokee Brave’. This group of disease resistant seedlings will be used to develop new cultivars of white flowering dogwood resistant to powdery mildew and to investigate the inheritance of powdery mildew resistance mechanisms in flowering dogwood.
Midwestern Retail Garden Centers Identify Satisfaction/Dissatisfaction with Supplying Wholesale Nurseries
Authors: Iles J.K. , Graves W.R. , Aiello A.S. , Haynes C.L. , Stone K.E.
Published: August 2020

A survey was conducted to assess the attitudes of Midwestern retail nursery operators concerning current marketing, promotion, sales, and service practices of their wholesale nursery stock suppliers. Completed questionnaires were received from 290 individuals (42.2% response rate). Respondents indicated quality of plant materials (96.5%), availability of plant materials in desired quantities (67.8%), wide assortment of plant materials (53.5%), and price of nursery stock (40.3%) were very important reasons for conducting business with a wholesale supplier. The majority of respondents said they were ‘very satisfied’ with the condition of bare-root trees and shrubs (75.1%), bedding plants (72.9%), herbaceous perennials and ornamental grasses (72.2%), container-grown trees and shrubs (72.0%), and balled-and-burlapped trees and shrubs (67.4%) shipped by their wholesale supplier. Over one-half (56.5%) also said they were ‘very satisfied’ with aquatic plant shipments. On those occasions when plants arrived in unsatisfactory condition, the most frequently cited problems were, dry bare-root stock (34.4%), physically damaged container-grown stock (56.0%) and balled-and-burlapped stock (40.0%), undersized herbaceous plants (20.3%), and aquatic plants damaged in transit (12.1 %). In general, retailers were most favorably impressed with the respectful and helpful way wholesalers attempted to meet their business needs (57.1%). Retailers were most frustrated with shortages, unauthorized substitutions, and last-minute cancellations (31.9%).
Use of Growth Retardants to Promote Flowering of Mountain Laurel, Kalmia latifolia L.
Authors: Banko Thomas J. , Bir Richard E.
Published: August 2020

Spray treatments of the growth retardants A-Rest (ancymidol at 0, 53, 106 ppm), Bonzi (paclobutrazol at 0, 10, 50, 100, 200, 400, 600 ppm) and Sumagic (uniconazole at 0, 10, 25, 50, 75, 100, 200, 300 ppm) were applied to container-grown Mountain laurel (Kalmia latifolia L.) to evaluate their effectiveness for promotion of flower initiation and inhibition of shoot elongation. A-Rest had no effect on flower initiation at the concentrations tested. Bonzi promoted a moderate increase in inflorescences on one cultivar evaluated. Uniconazole sprays of 50 ppm or higher increased inflorescence numbers of most cultivars tested. Application in the spring to plants two years from propagation gave the most consistent results, however, with some cultivars, applications following the second growth flush as late as early August promoted flower initiation. Uniconazole treatments also reduced stem elongation resulting in more compact growth. Stem elongation was retarded with increasing concentrations of uniconazole for the growth flush in the spring in the year following treatment. The results of this study show that Sumagic (uniconazole) in the range of 50 to 75 ppm increases inflorescence numbers without excessive growth inhibition when applied in the spring to most cultivars two years from propagation.
Spring Recovery of Constructed Wetland Plants Affects Nutrient Removal From Nursery Runoff
Authors: Arnold Michael A. , Lesikar Bruce J. , Kenimer Ann L. , Wilkerson Don C.
Published: August 2020

The nursery/greenhouse industry is the fastest growing segment of United States agriculture. Consumer demand for excellent product quality requires luxury applications of water and agricultural chemicals. These cultural practices tend to yield significant volumes of runoff rich in nutrients and pesticides. A capture and recycle system at the Nursery/Floral Crops Research and Education Center at the Texas A&M University was fitted with 12 sub-surface flow (SSF) and 12 free-surface flow (FSF) wetland cells. A single pass of runoff through constructed wetland cells provided substantial reduction of runoff nutrient concentrations, particularly NO3-N, without increasing electrical conductivity (EC), an indicator of salinity. Nitrate-N concentration reductions were greater in the FSF cells than SSF cells, while the greatest reductions in ammonium and nitrites were obtained with SSF cells. Growth of Iris pseudacorus L. and Canna x generalis L.H. Bailey during spring growth was greater in the FSF wetland cells, while that of Colocasia sp. Fabr. was greater in the SSF wetland cells. Equisetum hyemale L. grew equally well in both cell types. Interactions among irrigation water sources and container media types for growth indices occurred for Juniperus procumbens (Endl.) Miq. ‘Green Mound’ and Ilex vomitoria Ait. ‘Nana’, but not for Raphiolepis indica L. ‘Carmelita’.
Development of a Labor-Efficient Hand Pollination Procedure for Flowering Dogwood
Authors: Reed S. M.
Published: August 2020

The effect of frequency and timing of hand pollinations on seed set in flowering dogwood (Cornus florida L.) was studied. Six hand pollination treatments and an open-pollinated control were included in this study. The hand pollination treatments, which utilized non-emasculated flowers, were performed over a 12-day period beginning with the opening of the first flowers. All open flowers within five inflorescences of an individual plant were pollinated daily, every other day, every third day, every sixth day, on day 6 only, or on day 12 only. The experiment was repeated 10 times. There were significant differences among treatments for both percentage of inflorescences setting seed and mean number of seed produced per inflorescence pollinated. Daily or every other day pollinations produced significantly more seed and had more inflorescences setting seed than did the two treatments that involved a single pollination. Labor efficiency, which was measured as number of seed set divided by number of days on which pollinations were made, was greatest for the treatment that utilized two pollinations over the course of the study. Assuming that flower numbers are not limited, pollinating the same inflorescence twice is recommended for producing the most seed from controlled crosses of flowering dogwood.
Postemergence Control of Bittercress in Container-grown Crops
Authors: Altland James E. , Gilliam Charles H. , Olive John W. , Edwards James H. , Keever Gary J. , Kessler J. Raymond , Eakes D. Joseph
Published: August 2020

Three experiments were conducted to evaluate the effectiveness of postemergence applied herbicides for hairy bittercress (Cardamine hirsuta L.) control in container-grown crops. Manage (halosulfuron), Image (imazaquin), Action (fluthiacet-methyl), Resource (flumiclorac pentyl), Trimec Southern (Mecoprop + 2,4-D + dicamba), and Gallery (isoxaben) were applied to emerged bittercress in ‘Variegata’ and ‘Big Blue’ liriope. ‘China Girl’ holly and ‘Midnight Flare’ azalea were also treated with Manage, Image, Trimec Southern, and Gallery to evaluate injury. Among all experiments, Gallery provided 90 to 100% bittercress control at the labeled rate of 1.12 kg ai/ha (1.0 lb ai/A) with no injury to liriope, holly, or azalea. Among non-flowering bittercress, Manage applied at 0.035 kg ai/ha (0.031 lb ai/A) provided 90 to 100% bittercress control, with slight to moderate injury to ‘Variegata’ liriope; Image applied at 0.070 kg ai/ha (0.062 lb ai/A) provided 73 to 99.5% bittercress control and caused severe injury to azalea; and Trimec Southern applied at 0.31 kg ai/ha (0.28 lb ai/A) provided 50 to 100% bittercress control and caused severe injury to liriope and azalea. However, using the same rates applied to flowering bittercress Manage, Image, and Trimec Southern provided only 55, 6, and 50% bittercress control, respectively. Action and Resource did not control bittercress.
Compatibility Studies in Hydrangea
Authors: Reed S. M.
Published: August 2020

Improvement in cold-hardiness is needed in bigleaf hydrangea (Hydrangea macrophylla). Potential sources of cold-hardiness for enhancing the usefulness of this popular shrub include panicle hydrangea (H. paniculata), smooth hydrangea (H. arborescens), and oakleaf hydrangea (H. quercifolia). The objective of this study was to investigate the possibility of creating hybrids between these three species and H. macrophylla. In addition, self-compatibility of each of the species was evaluated to determine the need for emasculation when making controlled pollinations. Numerous cultivars of the species were utilized in both the self-pollination and interspecific hybridization studies. Number of flowers self-pollinated ranged from 1000 in H. arborescens to 3000 in H. quercifolia. Viable seeds were obtained from all species except H. arborescens. All five of H. quercifolia, 9 of the 18 H. paniculata, and 1 of the 8 H. macrophylla self progeny obtained survived. Emasculation of Hydrangea flowers to be used in controlled pollinations is therefore recommended. Seedlings were obtained from all interspecific crosses in which H. macrophylla was used as the maternal parent. All putative hybrid seedlings died either at the cotyledonary stage or while the first set of true leaves was expanding.
Propagation of Anemone x hybrida by Root Cuttings
Authors: Dubois Jean-Jacques B. , Blazich Frank A. , Warren Stuart L. , Goldfarb Barry
Published: August 2020

Stock plants of Anemone x hybrida Paxton ‘Honorine Jobert’ and ‘Richard Ahrens’ were grown in 3.8 liter (#1) containers for 30 weeks beginning in April, and fertilized daily with a complete nutrient solution providing 10, 40, 80 or 150 mg/liter (ppm) nitrogen (N), in a constant ratio of 1 ammonium: 2 nitrate. At the end of 30 weeks (November), 4-cm-long root cuttings were harvested from the stock plants and treated with the potassium salt of indolebutyric acid (K-IBA) at 0, 100, 500 or 1000 mg/liter (ppm), then placed in cell packs containing a pine bark-based substrate, one cutting per cell. The containers were arranged under intermittent mist in a heated greenhouse. Overall, 91% of the cuttings regenerated a complete plant. There were cultivar differences in regeneration, and the highest K-IBA concentration was inhibitory to ‘Honorine Jobert’. Nitrogen nutrition of the stock plants, K-IBA treatment of the root cuttings, and fresh weight of the root cuttings, had no significant effect on percent regeneration. Time to shoot emergence was reduced by higher rates of N applied to the stock plants, and increased at the highest concentration of K-IBA in ‘Honorine Jobert’, but not in ‘Richard Ahrens’. Dry weights of the regenerated plants increased with increasing weight of the cuttings from which they originated. They were related linearly to rate of N applied to the stock plants in ‘Honorine Jobert’, and quadratically in ‘Richard Ahrens’, with maximum plantlet weight predicted at 114 mg/liter (ppm) N. At the observed optimal rate of N applied to the stock plants, dry weights of the regenerated plants increased with increasing K-IBA concentration, in a quadratic manner. Maximum plantlet weight is predicted at 459 mg/liter (ppm) K-IBA in ‘Honorine Jobert’, and at 425 mg/liter (ppm) in ‘Richard Ahrens’.
Comparing Effects of Container Treatments on Nursery Production and Field Establishment of Trees with Different Root Systems
Authors: Schuch Ursula K. , Pittenger Dennis R. , Barker Philip A.
Published: August 2020

The objectives of this study were to determine the effects of container volume, container shape, and copper-coating containers on root and shoot growth during nursery production and after establishment in the field. Liners of ficus (Ficus retusa L. ‘Nitida’), a fibrous-rooted species, and Brazilian pepper (Schinus terebinthifolius Raddi.), a coarse-rooted species, were grown in regular or tall #1 containers in a glasshouse and were subsequently transplanted to the field or into #3 or #5 regular or tall containers. During the nursery phase, copper-coated containers improved rootball quality of ficus and pepper, but biomass production was not affected consistenly by copper coating. Tall, narrow versus regular containers restricted pepper growth throughout the nursery phase and field establishment, but had little effect on ficus. Biomass production of pepper trees was greatest in regular-shaped containers, and tall containers reduced growth consistently. Container shape did not affect shoot growth of ficus. The larger container volume of the #5 yielded greater total biomass of pepper and root dry weight of ficus during nursery production than did #3 pots. In the field, shoot dry weight of ficus was greatest when previously grown in #5 containers, and total biomass of pepper was greatest in both regular #3 or #5 containers.
Selling Plants through Horticultural Distribution Centers
Authors: Garber M.P. , Bondari K.
Published: August 2020

The services most frequently provided by horticultural distribution centers (HDCs) were delivery (98%), credit (90.2%) and information (84.3%). Only a small percentage (29.4%) of HDCs communicate with landscape architects and most HDCs try to influence their plant selection. The primary criteria in selection of plant suppliers is the ability of nurseries to supply consistent plant quality. When making decisions on which plants to purchase, HDCs rely on sales records or previous purchase history (87.8%), customer requests for plants (71.4%) and availability list from growers (55.1%). The projected changes in plant material requirements include larger plant sizes (24.1%), more color items (22.4%) and more container plants, especially trees (22.4%). The primary opportunities for plant producers to assist HDCs are in marketing support (21.3%), more frequent deliveries (19.7%) and meeting commitments for product (18.0%). The most common complaints from landscapers, the primary customer of HDCs, regarding plant material were high prices (23.8%) and inconsistency of available product (20.6%). The primary change in business activity planned by HDCs over the next five years was expansion of the plant product line (25.4%).
Consumers Preferences for Plant Size, Type of Plant Material and Design Sophistication in Residential Landscaping
Authors: Hardy Jill , Behe Bridget K. , Barton Susan S. , Page Thomas J. , Schutzki Robert E. , Muzii Karl , Fernandez R. Thomas , Haque Mary Taylor , Brooker John , Hall Charles R. , Hinson Roger , Knight Patricia , McNiel Robert , Rowe D. Bradley , Safley Charles
Published: August 2020

How much value do consumers place on a good landscape? Self-selected attendees to a Detroit, MI, flower show indicated that plant size was the most important factor in the perceived value of a landscape. Holding other factors equal, increasing from the smallest size plant generally available for installation to the largest size defined in our study increased perceived home value by 5.0%. Design sophistication was almost as important as size. Holding other factors equal, upgrading from a traditional foundation planting to a sophisticated design that incorporated multiple bed and curved bedlines increased perceived home value by 4.5%. The type of plant material used was the least important. The relative importance of plant material selection as a factor contributing value added to the home by the landscape was almost half that of plant size and over 40% less than design sophistication. The conjoint model produced from 158 survey responses predicted that from the least valued landscape to the most valued landscape the perceived value of the home increased 12.7%.
Colonization and Growth Effects of the Mycorrhizal Fungus Glomus intraradicies in a Commercial Nursery Container Production System
Authors: Davies F.T. , Saraiva Grossi J.A. , Carpio L. , Estrada-Luna A.A.
Published: August 2020

The objectives of this research were to demonstrate that mycorrhiza can survive in a commercial nursery container production system, and enhance plant productivity. Four species were used as host plants [Nandina domestica ‘Moon Bay’, Loropetalum chinense variety Rubrum ‘Hinepurpleleaf’ Plumb delight®, Salvia gregii, and Photinia fraseri]. Plants were inoculated with arbuscular mycorrhizal fungi, Glomus intraradices, and grown in a commercial nursery in Texas. For the first 5.5 months, plants were grown in #1 cans containing either 3 kg cu m (5 lbs cu yd) or 4.2 kg cu m (7 lbs cu yd) 24N–4P205–8K20. For the final 6.5 months of the study, plants were in larger containers, all of which contained 4.2 kg cu m (7 lbs cu yd) 24N–4P2O5–8K2O. The commercial inoculum of Glomus intraradices only enhanced growth of N. domestica. The shoot dry mass of mycorrhizal N. domestica plants at 3 kg cu m was the same as non-colonized plants at the higher fertility level of 4.2 cu m. Intraradical hyphae development and colonization (total arbuscules, vesicles/endospores, hyphae) of L. chinense, N. domestica, and S. gregii increased at the higher fertility levels. S. gregii had the greatest mycorrhizal development and a 216% increase in hyphae development and colonization at the higher fertility level.
Responses of Landscape Groundcovers to Minimum Irrigation
Authors: Pittenger Dennis R. , Shaw David A. , Hodel Donald R. , Holt Douglas B.
Published: August 2020

Four irrigation regimes based on percentages of real-time reference evapotranspiration (ET0) were applied to six widely used species of landscape groundcovers (Baccharis pilularis ‘Twin Peaks’, Drosanthemum hispidum, Vinca major, Gazania rigens v. leucolaena ‘Yellow Cascade’, Potentilla tabernaemontanii, and Hedera helix ‘Needlepoint’) during a 17-month period in Irvine, CA. Irrigation treatments (50%, 40%, 30% and 20% of ET0) were applied when accumulated real-time ET0 × treatment percentage reached 4.0 cm (1.6 in). Although the response to irrigation treatment was species dependent, Baccharis, Drosanthemum, and Hedera maintained at least minimally acceptable visual quality with applied water equal to 20% ET0, while Vinca required a minimum of 30% ET0. Acceptable visual quality of Gazania and Potentilla were not maintained at any treatment. Visual quality of Potentilla was better at ET0 greater than or equal to 30% ET0, but visual quality of Gazania was not improved with more water.
Growth Retardant Application to Canna × generalis ‘Florence Vaughan’
Authors: Bruner L.L. , Keever G.J. , Kessler J.R. , Gilliam C.H.
Published: August 2020

The effects of 15 to 45 ppm Cutless (flurprimidol), 2500/1500 to 7500/1500 ppm B-Nine/Cycocel tank mixes (daminozide/chlormequatchloride), and 20 to 60 ppm Sumagic (uniconazole) on the vegetative growth and flowering of Canna x generalis ‘Florence Vaughan’ were determined during container nursery production and landscape establishment. Vegetative heights 30 and 60 days after treatment (DAT) and vegetative and inflorescence heights at first and second flower were suppressed by all plant growth retardants (PGRs). There was no delay in flowering of the first inflorescence from any PGR treatment, and a three to seven day delay in flowering of the second inflorescence with only Sumagic. Vegetative height was suppressed quadratically 14–28% (30 DAT) and linearly 19–40% (60 DAT) by increasing Cutless rates. Inflorescence heights of plants treated with 15 or 30 ppm Cutless were suppressed proportionally to foliage heights without any detrimental effect on floral display. Heights of plants treated with Cutless and transplanted into the landscape at 60 DAT were similar to those remaining in containers at 90 DAT, and 7 cm (3 in) and 11 cm (3.5 in) taller at 120 and 150 DAT, respectively. Vegetative heights of plants in both locations were suppressed linearly by Cutless, 15–33% (90 DAT) and 7–12% (120 DAT) with height suppression effects dissipating by 150 DAT. Vegetative height was suppressed quadratically by B-Nine/Cycocel, 5–14% and 16–28% at 30 and 60 DAT, respectively. However, response was inconsistent with rate at all sampling dates both in containers and in the landscape. B-Nine/Cycocel treated plants were suppressed quadratically up to 33% (90 DAT) and up to 17% (120 DAT). Plants transplanted and treated with B-Nine/Cycocel were suppressed linearly 14–23% (90 DAT) and 6–16% (120 DAT). At 150 DAT, BNine/Cycocel treated plants were similar in height to control plants, with transplanted plants around 10 cm (4 in) taller than those remaining in containers. Sumagic suppressed vegetative height quadratically 28–33% (30 DAT) and 50–52% (60 DAT). At 60 DAT, the height suppression was excessive and leaf orientation was altered to a less upright position. Inflorescence height suppression by Sumagic was considered excessive with first and second flower occurring below the surrounding foliage. Compared to those transplanted into the landscape at 60 DAT, plants treated with Sumagic and remaining in containers were 12% (90 DAT), 36% (120 DAT), and 37% (150 DAT) shorter. In both locations, Sumagic suppressed vegetative height quadratically 46% (90 DAT) and 29% (120 DAT) compared to control plants. Compared to control plants, at 150 DAT, treated plants remaining in containers were suppressed to a greater extent (32–43%) than those transplanted into the landscape (11–14%).
Accelerated Flowering of Herbaceous Perennials Under Nursery Conditions in the Southern United States
Authors: Keever Gary J. , Raymond Kessler J. , Stephenson James C.
Published: August 2020

A study was conducted to determine the effects of night-interrupted (NI) lighting initiated at different times in late winter on several herbaceous perennials produced outdoors in a southern nursery setting. Treatments were NI lighting beginning February 1, February 15, March 1, March 15, and a natural photoperiod. NI lighting accelerated flowering in ‘Goldsturm’ coneflower (Rudbeckia fulgida Ait. ‘Goldsturm’) 26–46 days in 1999 and 51–75 days in 2000, and in ‘Coronation Gold’ yarrow (Achillea x ‘Coronation Gold’) 2–9 days in 1999 and 2–11 days in 2000. Flower and flower bud counts increased 82–100% in ‘Coronation Gold’ achillea in 1999, 44–51% in ‘Butterfly Blue’ scabious (Scabiosa columbaria L. ‘Butterfly Blue’) and 100–151% in ‘Alaska’ shasta daisy (Leucanthemum x superbum Bergmans ex. J. Ingram ‘Alaska’) compared to counts of plants under natural photoperiod. With few exceptions, plant height increased under all NI lighting treatments, but in only ‘Goldsturm’ coneflower did it reduce plant quality. Clump verbena (Verbena canadensis L.) was minimally affected by NI lighting, and speedwell (Veronica spicata L. ‘Sunny Border Blue’) was not affected at all.
Reducing White-tailed Deer Damage to Landscape Plants with Organic Products
Authors: Coker Christine Harris , Simonne Eric H. , Merritt Lani , Joseph Eakes D. , Keith Causey M. , Owen John , Osborne Jason
Published: August 2020

Chemical repellency is one of the most selective approaches to controlling white-tailed deer (Odocoileus virginianus) damage to horticultural crops. This study evaluated the continuous efficacy of selected organic products containing garlic, fish oil, or putrescent egg solids against feeding damage caused by confined white-tailed deer to Hosta fortunei L. H. Bailey ‘Francee’, Gomphrena globosa L. ‘Rose’, and Catharanthus roseus L. ‘Pacifica Red’. There was a significant interaction between plant species × product (p < 0.02) when all 3 plant species were tested together. When products were tested separately on single plant species, differences (p ≤ 0.05) were detected among products. All products displayed some level of damage control by reducing browsing damage compared to the untreated control; yet for each species, 100% destruction occurred within 5 to 6 days. Overall product efficacy was determined by Overall Rank Sum Index. When product ranks were calculated for the 3 species, products containing putrescent egg solids appeared to be more effective than products containing garlic and/or fish oil.
Survey of Insecticide and Miticide Usage by 158 Nurseries in Pennsylvania
Authors: Shetlar David J. , Heller Paul R.
Published: August 2020

Of 254 nurserymen surveyed in 7 Pennsylvania counties in 1979, 158 responded. Respondents used 3719.5 kg (8184 lb) of insecticides/miticides with an estimated cost of $64,436. They applied an average of 2.5 kg (2.2 lb/a) ai/ha. Seven pesticides accounted for 88.7% of the 29 pesticides used. The nurserymen tended to use low to moderate toxicity chemicals (96%); 74% used power spray equipment and 47% used wetting agents. The most commonly reported pests are listed.
Rooting Fraser Fir Stem Cuttings
Authors: Hinesley L. Eric , Blazich Frank A.
Published: August 2020

Since 1978, propagation of Fraser fir (Abies fraseri (Pursh) Poir.) by rooting stem cuttings has been investigated. A number of factors influencing rooting have been studied and the results are summarized. In addition, procedures for collecting and rooting cuttings are presented.
Nutrition and Performance of Container-Grown Japanese Black Pine Seedlings
Authors: Hathaway Robert D. , Whitcomb Carl E.
Published: August 2020

Growth of Japanese black pine (Pinus thunbergi Parl.) seedlings in containers was enhanced by incorporating a slow-release fertilizer (Osmocote) and micronutrient source in the growth medium while dolomite was detrimental. Seedlings transplanted into the field showed excellent survival, regardless of propagation treatment, however, plants grown with Osmocote and micronutrients in the container medium were significantly larger after 1 growing season. Root-to-shoot ratio was not related to survival or growth. Container-grown seedlings were larger after 3 months than 2-year-old conventional bed-grown plants and continued to outgrow the bed-grown seedlings after one year in the field.
Fertilization Practices as They Influence the Growth Rate of Young Shade Trees
Authors: van de Werken Hendrik
Published: August 2020

An overview of historical development of shade-tree fertilization practices and current state of the art is presented. Research involving 6 shade tree cultivars and their response to 4 fertilizer formulations and 2 methods of application is reported. Test results show that on phosphorus deficient soil, broadcast application of a slow-release complete fertilizer yielded larger trees than any of the other treatments. Urea formaldehyde applied in 46 cm (18 in) deep holes stimulated shade tree development least. The section, Application of Research Findings, covers applications of the ‘Universal Tree Fertilization Calculation’ formula for determining the amount of fertilizer to apply per tree based on the radius of the root system.
Grass Competition for Nitrogen Around Landscape Trees
Authors: Neely Dan
Published: August 2020

The sod around established saplings was treated with the nitrogenous fertilizer ammonium nitrate and/or the herbicide Roundup (glyphosate). Compared with untreated trees, all treatments increased the shoot growth of black walnut (Juglans nigra L.), and the trunk growth of sycamore (Platanus occidentalis L.), Norway maple (Acer platanoides L.), and honey-locust (Gleditsia triacanthos L. inermis Willd.). The response in walnut persisted for 2 growing seasons following application.
Growth Response of Annual Transplants and Physical and Chemical Properties of Growing Media as Influenced by Composted Sewage Sludge Amended with Organic and Inorganic Materials
Authors: Hemphill Delbert D. , Ticknor Robert L. , Flower D.J.
Published: August 2020

Composted sewage sludge was combined with several other organic and inorganic components to form 19 growing media. Increasing the proportion of sludge compost in media from 25 to 50% increased media pH, electrical conductivity (EC), airfilled pore space (AS), and nutrient levels, and usually increased growth of pansy, snapdragon, and cabbage plants. Of the other organic components, sawdust-based media had the highest pH, EC, and AS; sphagnum peat-based media the highest water holding capacity. Plant fresh weights were highest with bark, which produced media with highest retention of K, Ca, Mg, and Na. Of the inorganic components, pumice produced media with lower AS and lower yields of each crop than did perlite or vermiculite. Inorganic components had no effect on media pH or EC. Yields of all crops were usually higher in media containing compost than in 5 commercial potting mixes but less than in a fertilizer-amended bark medium. High yields appeared to be associated with higher medium AS and higher initial levels of major and minor plant nutrients.
Effects of Pruning and Staking on Landscape Trees
Authors: Harris Richard W.
Published: August 2020

Pruning and staking can be effectively used to develop structurally stable trees. The growth of young trees can be directed by pruning branches that are in unwanted permanent positions. Staking should be used primarily to protect and anchor young trees; support staking should be used only when plants are not able to stand upright without support.