bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Effects of Near-zero Leachate Irrigation on Growth and Water Use Efficiency and Nutrient Uptake of Container Grown Baldcypress (Taxodium distichum (L.) Rich.) Plants
Authors: Sammons Jonathan D. , Struve Daniel K. 
Published: August 2020

Abstract
Fertilization and irrigation practices affect water-and nutrient use-efficiencies in container-produced nursery crops. This study was conducted to determine if gravimetric monitoring of a plant-substrate-container unit could manage real-time irrigation volume to achieve a near zero leachate fraction and to study baldcypress (Taxodium distichum (L.) Rich.) growth, nutrient accumulation and water-use efficiency under a factorial combination of two irrigation leachate fractions and two controlled release fertilizer (CFR) rates. Baldcypress plants were grown at either 45 or 90 g of 15N–3.1P-12.5K (15-7-15 Multicote, six-month controlled release fertilizer top dressed on each container), and two irrigation rates, near-zero or 0.2 leachate fraction. Height growth, whole plant dry mass and shoot: root dry mass ratios, and water-use efficiency were not affected by a fertilizer and irrigation interaction. The higher fertilizer rate increased the whole plant N and K concentrations. Relative to a 20% leachate fraction irrigation regime, a near-zero leachate fraction decreased leachate volume and root, shoot and whole plant dry mass, while leachate electrical conductivity (EC), plant tissue mineral nutrient concentrations and water use efficiency increased. Although baldcypress whole plant dry mass was reduced under the near-zero leachate irrigation regime (presumably due to high soluble salt levels) there was no difference in height and stem diameter at the higher fertilizer rate between the two irrigation regimes. The near-zero leachate irrigation regime applied approximately one-half the irrigation volume of the 0.2 LF irrigation regime.
Control of Butterfly Bush with Postemergence Herbicides
Authors: Altland James , Ream Julie 
Published: August 2020

Abstract
Butterfly bush (Buddleja davidii) is classified as invasive in several parts of the United States. Two experiments were conducted to evaluate the effectiveness of four herbicides and two application methods on postemergence butterfly bush control. The four herbicides included: Roundup (glyphosate), Aquamaster (glyphosate), Garlon (triclopyr), and Arsenal (imazapyr). Application methods included spraying foliage with a CO2 backpack sprayer, and applying herbicide concentrate to recently cut stems (cut-stump method). Plants were treated in September with the maximum labeled rate for each herbicide. Cut-stump rates were determined such that the same amount of active ingredient was applied as in the spray treatments. Applications were made to plants several months after planting to simulate control of small recently germinated plants, and again to plants over 1 year old to simulate control of larger and more established plants. Summarizing results over both plant sizes and from two repetitions of the experiment, Roundup and Aquamaster provided higher levels of control compared to Garlon and Arsenal early in the experiment. Cut-stump applications provided more rapid control than spray applications. Despite differences in control when evaluated several weeks after application, all treated plants were dead when evaluated the following spring.
Effect of IBA Treatments, Bottom Heat, Stock Plant Location, and Cutting Type on the Rooting of Spigelia marilandica Cuttings
Authors: Pill Wallace G. , Goldberger Brian 
Published: August 2020

Abstract
Spigelia marilandica (India pink, pinkroot), a herbaceous perennial native to the United States, is underused in the nursery trade, in part because it is difficult to propagate. We found from the first of two studies conducted during winter 2007 that stem-tip cuttings collected from greenhouse-grown stock plants submersed in 3000 or 6000 ppm (mg·liter−1) potassium salt of indole-3-butyric acid (IBA) for one minute had greater percentage rooting (average 76.6) than cuttings not treated with IBA (46.9). Bottom heat [average 27.2C (81F)] compared to no bottom heat [23C (73F)] increased rooting percentage from 48 to 85%. The second winter 2007 study determined that rooting percentage according to method of application of 3000 ppm IBA was in the order: solution dip (60.1) &gt; powder dip (49.8) ≥ solution submersion (46.6) ≥ control (42.7). During summer 2009, bottom heat and the same methods of application of 3000 ppm IBA described above were applied to terminal (stem tip) or subterminal cuttings collected from greenhouse-or field-grown stock plants. While IBA application method had no effect on rooting of cuttings from greenhouse-grown stock plants (average 54.1%), it affected cuttings from field-grown stock plants in the order: solution submersion (80.1%) &gt; solution dip (54.4%) &gt; powder dip = control (average 29.5%). Solution submersion cuttings from field-grown stock plants had much greater rooting (80.1%) than those from greenhouse-grown stock plants (47.2%). Control and powder dip cuttings from greenhouse-grown stock plants had greater rooting percentage than those from field-grown stock plants. Cutting type had no effect on rooting of field-grown cuttings (average 48.4%). Terminal cuttings from greenhouse-grown stock plants had greater rooting (73.3%) than subterminal cuttings (34.8%).
Response of Two Salix L. Species to Water Deficit
Authors: Zhivotovsky Olena P. , Kuzovkina Yulia A. 
Published: August 2020

Abstract
Physiological responses and growth of two Salix species — S. miyabeana and S. cinerea — were compared during one and two drought cycles. Photosynthetic rate (Asat), stomatal conductance (gs), and transpiration (E) were determined for each species. The highest total biomass and root: shoot ratio were recorded for S. cinerea. After two drought cycles, S. cinerea had significantly higher Asat at wilting and recovery stages compared to S. miyabeana. In addition, after two drought cycles, the stem water potential and water use efficiency were higher in S. cinerea than in S. miyabeana. Based on the results obtained in this study, S. cinerea is more drought tolerant than S. miyabeana.
Remediation of Nitrogen and Phosphorus from Nursery Runoff during the Spring via Free Water Surface Constructed Wetlands
Authors: White Sarah A. , Taylor Milton D. , Chandler Stewart L. , Whitwell Ted , Klaine Stephen J. 
Published: August 2020

Abstract
Agricultural operations face increasing pressure to remediate runoff to reduce deterioration of surface water quality. Some nursery operations use free water surface constructed wetland systems (CWSs) to remediate nutrient-rich runoff. Our objectives were twofold, first to examine the impact of two hydraulic retention times (HRT, 3.5 and 5.5 day) on CWS performance, and second to determine if increased nutrient loading from internal CWS and nursery sources during the spring contributed to nutrient export in excess of regulatory limits. We quantified nutrient loading and removal efficiency in a free water surface CWS from late winter through late spring over three years and monitored various water quality parameters. Total nitrogen in runoff was reduced from 20.6 ± 2.8 mg·liter−1 (ppm) to 4.1 ± 1.3 mg·liter−1 (ppm) nitrogen after CWS treatment. Phosphorus dynamics in the CWS were more variable and unlike nitrogen dynamics were not consistently influenced by water temperature and hydraulic loading rate. Phosphorus concentrations were reduced from 1.7 ± 0.8 mg·liter−1 (ppm) PO4-P in influent to 1.2 ± 0.6 mg·liter−1 (ppm) PO4-P in CWS effluent, but substantial variability existed among years in both phosphorus loading and removal rates. The CWS was able to efficiently remediate nitrogen even under high spring loading rates.
Irrigation Pond Characterization and Analysis: Impact of Weather and Management
Authors: Fox Laurie J. , Struik Paul C. , Appleton Bonnie L. , Nowak Jerzy E. 
Published: August 2020

Abstract
Weather and management practices were monitored to assess the impact on water quality at four stormwater retention ponds used for irrigation. Two retention ponds were located at Bayville Golf Club (BGC) in Virginia Beach, VA, and two were located at Knotts Creek Nursery (KCN) in Suffolk, VA. Total dissolved N concentrations were examined at increasing depths and over time at the pond inflows and middles. Multiple fertilizer products with variable analyses were applied more frequently at BGC, but N concentrations were consistently higher at KCN. In 2002, a drought year, water temperatures fluctuated little over the season or with depth, regardless of location. N concentration ranges were 1.0—3.5 mg·liter−1 (ppm) at BGC and 2.5—6.0 at KCN. Nitrogen concentrations fluctuated as water depth increased. In 2003 rainfall was above average. Water temperatures fluctuated more over the season than in 2002 and with increasing depth. N concentration ranges were 0.75—4.2 mg·liter−1 (ppm) at BGC and 0.5—6.0 at KCN; and were consistent as water depth increased. Both water temperatures and N concentrations fluctuated dramatically at the inflow locations compared to the middles of the ponds.
Green Roof Growing Substrates: Types, Ingredients, Composition and Properties
Authors: Ampim Peter A.Y. , Sloan John J. , Cabrera Raul I. , Harp Derald A. , Jaber Fouad H. 
Published: August 2020

Abstract
Although development of low (extensive) and high (intensive) maintenance green roof systems has progressed significantly, studies on the function of the growing substrate as a living constituent are lacking. The objective of this review paper is to summarize current scientific knowledge on the components, composition, and characteristics of green roof substrates and to identify future research needs. Due to variations in climate and desired plant types, there is no universal growing substrate. An appropriate substrate is expected to provide permanent physical support for plants and possess a fine balance between free drainage and adequate plant available water and nutrient retention. Typical substrate components include minerals in natural or modified forms such as sand, lava rock, or expanded shale, clay and slate; recycled waste materials like crushed bricks or tiles, crushed or aerated concrete and subsoil; stabilized organic matter such as composts; and plastic materials and slow release fertilizers. Proportions of components vary among substrates based on target vegetation, green roof type, and other considerations. Better green roof management for maximum benefits will require characterizing, quantifying and understanding the impacts of plant species and building attributes such as aspect, slope, height and heating on substrate performance, and should be considered for future research.
Entomosporium Leaf Spot Control on Red-tip Photinia in the Landscape
Authors: Hagan A.K. , Arkidge J.R. 
Published: August 2020

Abstract
In 2006, 2007, and 2008, efficacy of the soil-applied fungicide drench All-In-One Rose & Flower Care [All-In-One] (tebuconazole) was compared with the foliar-applied fungicides Daconil Weather Stik (chlorothalonil), Immunox Multipurpose Fungicide (myclobutanil), RosePride Disease Control Concentrate (triforine), and Disease Control for Roses, Flowers & Shrub Concentrate (tebuconazole) for the control of Entomosporium leaf spot on field-grown red-tip photinia (Photinia × fraseri ‘Birmingham’). While the label rate of All-In-One drench was poured over the soil surface around the base of each plant at monthly intervals, the foliar applied-fungicides were applied at label rates at 2-week intervals to runoff. Over the study period, drenches of All-In-One failed to protect photinia from Entomosporium leaf spot, while the foliar-applied fungicides significantly reduced disease levels. Defoliation on the non-fungicide treated controls was similar to the All-In-One drench and ranged over the study period from 25 to nearly 75%. In contrast, little if any leaf spotting and no defoliation occurred in any of the study years on the photinia treated with Daconil Weather Stik, Immunox Multi-purpose Fungicide, RosePride Disease Control Concentrate, and Disease Control for Roses, Flowers & Shrub Concentrate. Poor efficacy of the All-In-One was attributed to an inadequate concentration of the fungicide component tebuconazole when applied at the label drench rate.
Evaluation of Powdery Mildew Resistance in Hydrangea macrophylla
Authors: Windham Mark T. , Reed Sandra M. , Mmbaga Margaret T. , Windham Alan S. , Li Yonghao , Rinehart Timothy A. 
Published: August 2020

Abstract
Powdery mildew, Erysiphe polygoni DC, can be a significant problem on Hydrangea macrophylla (Thunb.) Ser. in the landscape in late summer to fall and during greenhouse propagation or production of potted plants. Because very little information related to sources of resistance is available, 90 H. macrophylla cultivars were evaluated for resistance to powdery mildew over a 3-year period. This included 69 H. macrophylla ssp. macrophylla and 18 H. macrophylla ssp. serrata (Thunb.) Makino cultivars, along with three cultivars that are hybrids between the two subspecies. Significant differences among cultivars to powdery mildew were found in all three study years. Three cultivars, ‘Amagi Amacha’, ‘Shirofuji’ and ‘Veitchii’, were among the most resistant each year. ‘Diadem’, ‘Komachi’, and ‘Omacha’ were highly resistant in 2006 and 2008, but only moderately resistant in 2007. ‘Komachi’ and ‘Shirofuji’ were considered unsuitable for breeding purposes as they do not appear to produce fertile flowers. ‘Veitchii’ was the only member of H. macrophylla ssp. macrophylla with a high level of powdery mildew resistance; while all other resistant cultivars were members of H. macrophylla ssp. serrata, not all members of this subspecies are resistant. Results of this study will be useful in breeding powdery mildew resistant H. macrophylla.
Physical and Chemical Properties of Green Roof Media and Their Effect on Plant Establishment
Authors: Olszewski Michael W. , Young Courtney A. 
Published: August 2020

Abstract
There are few research reports on components of green roof media. Better elucidation will allow landscape installers to select the ideal medium for individual or regional situations. The present study examined the effects of heat-expanded clay media components on: (1) physical and chemical properties and (2) growth of Sedum floriferum (stonecrop) and Dianthus gratianopolitanus (dianthus) plugs on a green roof. The addition of fine grade components caused an increase in bulk density and a decrease in total porosity, aeration porosity, and aeration porosity at applied suction pressure of 6.3 kPa. Container capacity reached a maximum following the addition of 40–60% (by vol) fine grade particles. Stonecrop and dianthus plugs were planted in early summer (June 29, 2010) into 6.4 cm (2.5 in) depth media containing 10–60% fine or medium grade heat-expanded clay located in a green roof garden. By early autumn (October 3, 2010), dianthus cover and plant weight were greatest in media containing 50–60% fine grade heat-expanded clay or 60% medium grade heat-expanded clay while stonecrop growth was inadequate regardless of media type.
Characterization of Hydrangea macrophylla Cultivars by the Anthocyanin Content in their Sepals
Authors: Schreiber Henry D. , Wade Samantha E. , Mayhew Kelly M. , Cobb Jason A. 
Published: August 2020

Abstract
In order to ascertain the role of anthocyanin content on the color and brightness of Hydrangea macrophylla sepals, anthocyanin contents of different colored sepals were measured for numerous commercial cultivars. Anthocyanin contents were primarily determined by extraction of the pigment, then measurement by differential spectrophotometry. Concentrations ranged from about 25 to over 400 μg delphinidin-3-glucoside per g of fresh sepal, with the magnitude roughly proportional to the perceived intensity of sepal coloration for that Hydrangea macrophylla cultivar. However, the anthocyanin content was independent of the sepal color, being the same for red, purple, or blue sepals of the same cultivar. Even though significant sepal-to-sepal variation in color intensity existed within a single inflorescence, the extractable anthocyanin content was constant for a specific cultivar. Accordingly, Hydrangea macrophylla cultivars were classified in terms of their color brightness or anthocyanin content in sepals as blush (very light colored, 25 to 60 μg·g−1), cold-hardy (light colored, 80 to 120 μg·g−1), classic (medium colored, 140 to 190 μg·g−1), vivid (deep colored, 230 to 270 μg·g−1), or vibrant (very deep colored, &gt;300 μg·g−1) at peak bloom. The anthocyanin content of the sepals steadily increased as the inflorescence approached peak bloom, remained constant for a week or more, then decreased. The cultivar-dependent anthocyanin contents of the sepals can be used, in part, to rationalize the relative bluing capability of the various Hydrangea macrophylla cultivars.
Propagation of Osmanthus heterophyllus ‘Variegatus’ by Stem Cuttings
Authors: Lambert Christopher R. , Blazich Frank A. , LeBude Anthony V. 
Published: August 2020

Abstract
Nontreated softwood cuttings of Variegatus' osmanthus [Osmanthus heterophyllus (G. Don) P.S. Green ‘Variegatus’] collected in early June 2009 and late May 2010 rooted at &gt; 70%. Treatment of cuttings with solutions of the potassium (K) salt (K-salt) of indolebutyric acid at 500 to 2000 mg·liter−1 (ppm) was generally ineffective and does not appear to be necessary for satisfactory rooting.
Preference and Performance of Black Cutworm (Lepidoptera: Noctuidae) on Poa Species
Authors: Hong Seung Cheon , Chris Williamson R. , Held David W. 
Published: August 2020

Abstract
Black cutworm (Agrotis ipsilon Hufnagel) is a destructive pest of golf course turf. Previous work suggests that Poa pratensis ‘Midnight’ is resistant to black cutworm, but it is not known if resistance also exists among other Poa species and cultivars. This study compared preference and performance of black cutworm on Poa species and cultivars to a susceptible host plant, creeping bentgrass (Agrostis stolonifera L. ‘Penncross’) in laboratory choice feeding assays and rearing experiments. Seven-and 14-day-old larvae were used in performance feeding tests. Larvae reared on all Poa spp. exhibited significantly lower developmental and survival rates than larvae fed creeping bentgrass. Young (7 days old) larvae did not survive to pupation. Although older (14 days old) larvae pupated and eclosed on Poa, larval weight gain was significantly lower than those reared on creeping bentgrass. In choice feeding bioassays, regardless of larval stage, black cutworm preferred creeping bentgrass over all Poa species and cultivars. The results of this research suggest that although Poa species are generally resistant to black cutworm, the resistance varies among cultivars and insect growth stage.
Cultural Treatment and Cutting Type Affects Growth of ‘Heritage’ Birch Rooted Cuttings
Authors: Struve Daniel K. 
Published: August 2020

Rooted cuttings of Betula nigra ‘Heritage’ originating from short shoots were either staked and lateral shoots pruned to a 3 node length or were unstaked and unpruned. One hundred and twenty-five days following propagation, the pruned and staked plants had higher net assimilation rates and lower leaf area ratios than unstaked and unpruned plants. No differences in relative growth rates, total dry weight, root/shoot ratios or shoot length were observed between control and treated plants. Pruned and staked plants had, relative to unstaked and unpruned, less leaf surface area composed of fewer but larger leaves which produced more grams of dry weight per cm2 leaf surface area per day. Pruning and staking maximized economically important dry matter production without reducing total dry weight.
Plants originating from long shoots had greater root, shoot and total dry weights, and required less staking to produce upright growth than plants originating from short shoots. By exploiting the beneficial topophysis growth of long shoots, nursery productivity can be increased.
Spray deposition inside multiple-row nursery trees with a laser-guided sprayer1
Authors: Zhu H. , Liu H. , Shen Y. , Liu Hengyu , Zondag R. H. 
Published: August 2020

Abstract
Multiple-row container-grown trees require specially designed sprayers to achieve efficient spray delivery. A five-port air-assisted sprayer with both automatic and manual control modes was developed to discharge adequate spray deposition inside multiple-row trees. The sprayer resulted from integration of a high-speed laser-scanning sensor with a sophisticated nozzle flow control system, an embedded computer with a touch screen, a Doppler speed sensor, a specially-designed algorithm and an air-assisted sprayer base. It was able to detect target tree presence and measure target tree size, shape and leaf density. The sprayer then controlled the spray output of each nozzle to match tree structures. The sprayer was tested for its sprayer deposition quality inside canopies in a four-row sterling silver linden (Tilia tomentosa 'Sterling Silver' Moench) field and another six-row northern red oak (Quercus rubra L.) field. Tests were conducted with the sprayer in variable-rate application (VRA) and constant-rate application (CRA) modes. The average spray deposit on foliage of trees was 1.37±0.47 μL cm−2 from VRA and 1.29±0.42 μL cm−2 from CRA in linden, and was 2.15±0.57 μL cm−2 from VRA and 2.72±0.94 μL cm−2 from CRA in red oak, respectively. In comparison, spray coverage on foliage of trees was 19.8±3.0% from VRA and 20.9±4.3% from CRA in the linden trial, and was 27.9±3.7% from VRA and 30.5±5.4% from CRA, respectively, in the red oak trial. The newly developed air-assisted sprayer in both VRA and CRA modes would be able to discharge adequate spray deposition inside multiple-row tree plants while conserving pesticide.
Index words: environmental protection, pest control, pesticide, precision sprayer, spray coverage.
Species used in this study: sterling silver linden (Tilia tomentosa 'Sterling Silver' Moench), northern red oak (Quercus rubra L.).
Effect of Propagation Tray Design on Early Stage Root Development of Acer rubrum, Quercus rubra, and Populus tremuloides 1
Authors: McGrath Darby , Henry Jason , Munroe Ryan , Agro Erin 
Published: August 2020

Abstract
This experiment investigated the effect of different plug-tray cell designs on root development of red maple (Acer rubrum), red oak (Quercus rubra), and quaking aspen (Populus tremuloides) seedlings. In April of 2015, seeds of each species were sown into three plug trays with different substrate volumes and grown for 17 weeks. Two trays had permeable walls for air-pruning, one with vertical ribs and one without. The third tray had impermeable plastic cell walls. Harvested seedlings were analyzed for root dry weight, length, volume, surface area and number of deflected roots. Root length per volume was highest in the impermeable-walled tray for red maple and quaking aspen. The total numbers of deflected root systems were higher for all species in the impermeable-walled tray. Seedlings grown in the air-pruning trays had smaller proportions of deflected root masses. Greater substrate volume did not influence root deflection development. The air-pruning tray without vertical ribs had the lowest total number of root masses with misdirected roots and lower proportions of root masses with misdirected roots for all species. These results indicate that improved root architecture in root-air pruning tray designs is achievable in tree propagation; however, vertical plastic structures in air-pruning trays can still cause root deflections.
Index words: Deflected roots, air-pruning, seedling, propagation, plugs, root architecture.
Species used in the study: red maple (Acer rubrum L.); red oak (Quercus rubra L.); quaking aspen (Populus tremuloides Michx.).