bluuebunny/crossref_metadata_2025 huggingface dataset:
Intensity of Anthracnose on Three Wintercreeper Euonymus Cultivars as Influenced by Fungicide Program
Authors: Cole Janet C. , Schupbach Stephanie L. , Conway Kenneth E.
Published: August 2020

Plants of three cultivars of wintercreeper euonymus (Euonymus fortunei (Turcz.) Hand.-Mazz. ‘Emerald Gaiety’, ‘Emerald ‘n Gold’ and ‘Canadale Gold’) in containers were sprayed at 7-or 14-day intervals depending on label directions with mancozeb, propiconazole, or thiophanate methyl alone or in tank mixes of two fungicides to determine efficacy in controlling anthracnose symptoms caused by Colletotrichum gloeosporioides (Penz.) Penz. & Sacc. Each fungicide was applied at the maximum label rate and half the maximum label rate when applied alone or at the maximum label rate when applied in combination. Plants were rated for disease symptoms monthly at two sites in 2002 and at one site in 2006. At Stillwater, disease ratings were typically lowest on ‘Emerald Gaiety’ and highest on ‘Emerald ‘n Gold’ on all rating dates in both years. Plants of all three cultivars and in all fungicide treatments at Stillwater had sufficient disease symptoms in July, August and September of both years to be considered nonsalable. When applied alone, mancozeb typically provided better anthracnose control than propiconazole or thiophanate methyl. Disease ratings from plants receiving any fungicide mixture were generally similar to those of plants receiving mancozeb alone. At Park Hill, disease ratings differed among cultivars only in August and September, and ratings did not differ among fungicide treatments on any rating date. Disease severity was substantially less at Park Hill than Stillwater in 2002, presumably the result of greater shade intensity and lower temperatures.
Zein-based Bioplastic Containers Alter Root-zone Chemistry and Growth of Geranium
Authors: Helgeson Matthew S. , Graves William R. , Grewell David , Srinivasan Gowrishankar
Published: August 2020

Bioplastic containers made from zein, a protein from corn (Zea mays L.), have been developed but not evaluated as alternatives to conventional, petroleum-based plastics. We tested the hypothesis that biodegradation of zein containers provides nitrogen (N) that promotes growth of plants and examined whether plants grown in zein containers could be transplanted successfully without removing the container, thus eliminating the need to dispose of containers. Zein containers provided root zones of geranium (Pelargonium ×hortorum L.H. Bailey) with up to 298 and 277 mg·kg−1 of NH4+-N and NO3−-N, respectively, and unlike geraniums in conventional plastic containers, leaves of plants in zein containers remained dark green when produced without fertilization. Electrical conductivity and pH of the substrate in zein containers increased above ranges recommended for many horticultural crops, and NO2−, which can be toxic to plants, was present in the substrate. These chemical changes may have been responsible for reduced canopy height and width, surface area of selected leaves, length of root systems, and dry weight of shoots of geraniums in zein containers compared with geraniums in conventional plastic containers. In a second experiment, when geraniums were transplanted without removing zein containers, growth of roots and shoots was reduced until after six weeks, when biodegradation of containers was nearly complete, and extension of roots past the zone of the degraded container was documented approximately 12 weeks after transplanting. Geraniums can be produced and transplanted in containers made from zein, but additional research must solve problems that result from altered root-zone chemistry during production and from chemical and physical impediments that delay transplant success.
Effects of Cyclanilide and Benzyladenine Tank Mixes on Shoot Production and Growth of Three Woody Landscape Species during Production
Authors: Farris M.E. , Keever G.J. , Kessler J.R. , Olive J.W.
Published: August 2020

A study was conducted to determine if there were synergistic effects from applying two plant growth regulators (PGRs), cyclanilide (CYC) and benzyladenine (BA), with cytokinin properties on Rhaphiolepis sp. (L.) Lindl. ‘Conor’ and ‘Snow White’ (Indian hawthorn), Rhododendron L. ‘North Lake Beauty’ (azalea), and Ilex crenata Thunb. ‘Sky Pencil’ (Japanese holly) during nursery production. Foliar applications of 100 or 200 ppm CYC promoted new shoot development in all species, whereas 2500 ppm BA either had no effect or suppressed shoot development, except in one of two experiments when shoot development was promoted in holly. With no species was there a synergistic effect on shoot development from combining the two PGRs, even when both PGRs individually promoted new shoot development in holly. Indian hawthorn and holly developed transient symptoms of toxicity in response to CYC, BA, and CYC + BA combinations that had dissipated by the end of the growing season and had no lasting effects on plant quality.
A Comparison of WholeTree and Chipped Pine Log Substrate Components in the Production of Greenhouse Grown Annuals
Authors: Gaches Whitney G. , Fain Glenn B. , Eakes Donald J. , Gilliam Charles H. , Sibley Jeff L.
Published: August 2020

WholeTree (WT) and chipped pine logs (CPL) are potential new sustainable greenhouse substrate components made by milling chipped pine trees and/or pine logs (Pinus taeda L.). Two experiments were conducted to evaluate the growth of Catharanthus roseus L. ‘Grape Cooler’ and Impatiens walleriana Hook.f. ‘Dazzler Apricot’ in 1:1 (v:v) WT:peat (WTP) and 1:1 (v:v) CPL:peat (CPLP), and to compare physical properties of those substrates. In Experiment 1 WTP had 76.8% container capacity (CC) and 96.4% total porosity (TP) while CPLP had 72.4% CC and 90% TP; air space (AS) and bulk density (BD) were similar. In Experiment 2 there were no differences in physical properties. In Experiment 1 EC peaked at 14 days after potting (DAP) and decreased through the remainder of the study. At 0 DAP pH ranged from 4.2–4.3 and increased to a range of 6.4 to 6.8 at 42 DAP. This trend was similar in Experiment 2, except that EC peaked at 7 DAP. In impatiens, plants were similar in Experiment 1 but those grown in WTP in Experiment 2 had bloom counts of 37.3 compared to 27.9 for plants grown in CPLP. With vinca, in Experiment 1 plants grown in CPLP had a dry weight of 7.3 g as compared to 6.9 g for plants grown in WTP, but there were no differences in Experiment 2. Results indicate that growers could use CPL and/or WT interchangeably, depending on available resources.
Day/Night Temperatures Influence Growth and Photosynthesis During Containerized Production of Selected Species of Helleborus (Hellebores)
Authors: Lowder Adam W. , Kraus Helen T. , Blazich Frank A. , Warren Stuart L.
Published: August 2020

Containerized seedlings of Helleborus foetidus L. (stinking hellebore), H. niger L. (Christmas rose), and H. ×hybridus L. (Lenten rose) were grown under long-day conditions in controlled-environment chambers for 95 days with 9-hr days of 14, 18, 22, 26, or 30C (57, 64, 72, 79, or 86F) in factorial combination with 15-hr nights of 10, 14, 18, 22, or 26C (50, 57, 64, 72, or 79F). Long-day conditions were provided by a 3-hr night interruption. Growth of each species responded differently to day and night temperatures. Calculated maximum root, top, and total dry weight, and leaf area of H. foetidus occurred with days/nights of 20/15, 18/13, 19/14, and 18/15C (68/59, 65/55, 66/57, and 65/59F), respectively. While night temperature (NT) had no effect on root:top ratio [RTR (root dry weight ÷ top dry weight)], RTR was greatest (0.65) with days of 22C (72F). Helleborus niger had calculated maximum root dry weight and total dry weight with days of 14C (57F) and nights of 16 and 13C (60 and 55F), respectively. Top growth of H. niger decreased linearly as NTs increased for days of 14 or 22C (57 or 72F). Day temperatures (DTs) had no effect on RTR, whereas RTR responded quadratically as NT increased with a calculated maximum RTR at nights of 19C (66F). Leaf area was maximized at days/nights of 14/10C (57/50F). At days of 22 or 26C (72 or 79F), top growth of H. ×hybridus responded quadratically as NT increased with maxima occurring at nights of 18 or 17C (64 or 63F). Root dry weight responded quadratically at days of 14, 22, or 26C (57, 72, or 79F) and calculated maxima occurred with nights of 18C (64F). At days of 22 or 26C (72 or 79F), there were quadratic responses in total dry weight with calculated maximum growth of H. ×hybridus at nights of 18 or 17C (64 or 63F), respectively. For days of 14, 22, or 30C (57, 72, or 86F), there were quadratic responses in RTR with greatest RTR calculated at nights of 15, 18, or 16C (59, 64, or 60F), respectively. There were quadratic responses at days of 22 or 26C (72 or 79F) for leaf area with calculated maxima at nights of 18 or 17C (64 or 63F), respectively. As DTs increased from 14 to 30C (57 to 86F) net CO2 assimilation (PN) of H. ×hybridus also increased linearly whereas increased NTs had no effect on PN. In contrast, stomatal conductance was not impacted by DT or NT.
A Survey Method to Gauge Public Interest in Programs, Activities, and Events at Arboreta and Botanic Gardens
Authors: Conklin Janine R. , Drackett Patricia R.
Published: August 2020

To provide arboreta and botanic gardens with a guide to determine public interests in programs at their institution, a case study was completed of the Crosby Arboretum, Mississippi State University. ‘Community’ was defined as participants that resided within 105 km (65 mi) of the arboretum (97% of community respondents) and attended the Picayune Street Fair. ‘Visitors’ were defined as respondents that attended the Piney Woods Heritage Festival at the arboretum. At each event, an intercept survey was conducted in Picayune, MS, during November 2009 where self-selected respondents (n = 271 for community and n = 56 for visitors) answered six demographic and 11 program, activity, and event questions. Both groups were similar in all demographic variables except age (9 year average age difference) and the number of homes without children (60 and 76%). Each group was most interested in continuing education classes, craft exercises, music performances, fitness walks, and workshops. The community and visitors were the least interested in book clubs, dance instruction, preschool activities, and scout programs. This study can be adapted by any botanic garden or arboretum and may be useful in planning current and future programs which target visitor or community interests for repeated visits to the site.
In Vitro Propagation of Viburnum opulus ‘Nanum’
Authors: Hildebrandt Virginia , Harney Patricia M.
Published: August 2020

Explants of actively growing shoot tips from greenhouse-grown plants of Viburnum opulus ‘Nanum’ initiated new shoots on a modified Murashige and Skoog (MS) revised medium plus 0.1 mg/L indoleacetic acid (IAA). These shoots were transferred for proliferation to the same medium, but with 1 mg/L 6-benzylamino purine (BA) replacing IAA and the addition of 2.5 mg/L 2-iso-pentenyladenine (2iP). Both adenine sulfate AdS) and NaH2PO4.H2O inhibited shoot proliferation, while gibberellic acid (GA3) and glycine had no effect. The shoots could be rooted either in the basal medium without cytokinin or in vermiculite under mist.
Effect of Growth Regulator and Nitrogen on Height and Branching of Skimmia reevesiana
Authors: Ryan George F.
Published: August 2020

Application of gibberellins A4 + 7 (GA4 + 7) or 6-benzylamino purine (BA) stimulated a second growth flush on plants of Skimmia reevesiana Fort. that had completed normal spring growth. Plants treated with GA4 + 7 were up to 130% taller than untreated plants at the end of the first season, and up to 50% taller after a growth flush the following spring without re-treatment. The number of shoots was increased more than 100% by BA at 4000 ppm, without affecting height. Promalin (BA + GA4 + 7) at 2000 ppm of each active ingredient increased height 50% the year of treatment, and the number of shoots more than 160%. There was not a significant difference in height after the next spring flush. Increasing the amount of nitrogen (N) supplied to the plants increased the number of shoots the second season and decreased plant height. Application of GA4 + 7 tended to counteract these effects of N.
Effects of Propagation Container Dimensions, and Media on the Growth of 4 Nursery Crops
Authors: Threadgill C. Chris , Whitcomb Carl E. , McNew Ronald
Published: August 2020

Four woody nursery crops were propagated in 3 media in containers with 3 depths and 3 diameters. A container, 7.0 cm (2.8 in) depth and 5.6 cm (2.2 in) diameter provided the best plant performance both during propagation and production. Volume trend analysis suggests that depth and diameter, not just increasing volume, influence plant response. Performance during propagation was best in peat and perlite, followed by peat and vermiculite and 100% peat. However, subsequent plant growth during the growing season was best when the rooting medium was 100% peat.
Effects of Soil pH on Four Field-Grown Nursery Crops
Authors: Gilliam C.D. , Eason J.T. , Evans C.E.
Published: August 2020

Four woody nursery crops were grown for 3 years (1981–1983) in plots with varying pH levels. Greater growth of ‘Compacta’ Japanese holly and Foster's holly occurred in 1981 and 1982 at lower pH levels (4.1–5.8). However, Mn phytotoxic symptoms appeared on ‘Compacta’ Japanese holly dunng the fall of 1982. Foliar Mn levels of all 4 species exceeded 2500 ppm when grown at the lowest pH level, with the exception of Foster's holly in 1983. Growth of ‘Nellie R. Stevens’ holly was not affected by pH, while Taxus growth was enhanced in 1983 at the higher pH levels (4.7–5.9). Foliar nutrient concentration trends were similar among the 4 crops.
Flavonoid Shifts During Developmental Stages of Spathiphyllum Inflorescences
Authors: White Roseann S.
Published: August 2020

Flavonoids of spadix and spathe samples representing 6 different stages of maturation were extracted in methanol and analyzed by paper chromatography. Although the flavonoid composition appeared similar for the different developmental spadix stages, flavonoid diversity increased during maturation. Similar results were obtained from spathe samples. The flavonoid chromatographic profile obtained with leaf blades also differed markedly from that of either the spathe or spadix. These preliminary chromatographic studies demonstrate phytochemical diversity not only between different plant organs but within the same organ at different developmental stages.
Evaluation of Growth Regulator Effects of Embark, Atrinal, Blazer, and Bayleton on Container-Grown Azaleas
Authors: Banko Thomas J.
Published: August 2020

Three chemicals that are not normally used to promote branching were evaluated for their abilities to increase shoot production of containerized outdoor-grown azaleas and compared with Atrinal (dikegulac sodium) and manual shearing. In an initial experiment, spray applications of Embark (mefluidide) at 0.38% ai (active ingredient) promoted more new shoots than the sheared only controls and slightly more than Atrinal (0.5% ai) for most azalea cultivars. In subsequent experiments, applications of Embark at 0.3 and 0.4% ai generally promoted fewer new shoots than Atrinal (0.5% ai) and, in most cases, smaller plants. Applications of Blazer (acifluorfen, 4 mg ai per pot) as a soil drench consistently promoted more new shoots than Atrinal (0.5% ai), however, plant size was also smaller. Lower levels of Blazer (1 to 3 mg ai per pot) resulted in larger plant sizes, but inconsistent shoot production. Spray applications of Bayleton (triadimefon) at 0.06% ai had no significant effect on azalea shoot production or plant growth.
Horticultural Oils
Authors: Johnson Warren T.
Published: August 2020

Horticultural oils are among the safest of pesticides. Lack of product identification through the label makes it difficult for the field user to know what product was actually used in experimental studies. A minimum standard for product identification is suggested. Phytotoxicity, while relatively uncommon, continues to cause fears on the part of nurserymen and spray contractors. Factors that must be taken into account before spraying oil include dosage, timing with regard to plant phenological development and climatic conditions, and an awareness of sensitive plant species. A list of sensitive plants is given. A new expression of pesticide resistance through the thickening of the test of certain armored scales was observed.
Effects of Controlled-Release Fertilizer Placement on Nutrient Leaching and Growth of Bedding Impatiens
Authors: Andiru G.A. , Pasian C.C. , Frantz J.M.
Published: August 2020

Bedding impatiens plants were grown with a 16N-3.9P-10K controlled-release-fertilizer (CRF) of 5–6 or 8–9 month longevities placed at four positions in the container: top-dressed, incorporated, top-one-third, and bottom. These were compared to plants grown with a 20N-4.4P-16.6 water-soluble fertilizer (WSF) at a rate of 150 mg·L−1 nitrogen (N) (150 ppm N). All treatments received the same volume of tap water (CRF treatments) or fertilizer solution (WSF treatment), which was enough to achieve a 20 to 30% leaching fraction. Leachates were collected and measured at each irrigation and the concentrations of N, phosphorous (P), and potassium (K) were measured. Shoot dry weight (SDW) and canopy cover (CC) were also determined. Fertilizing with WSF produced plants of similar size as CRF treatments. CRF applied at the bottom of the substrate leached the highest amount of N among all treatments. Higher concentrations for most nutrients were measured in the leachates from containers treated with 5–6 month CRF during the first 20 d after planting than the next 23 to 34 days. The higher levels of nutrients in the leachates observed within two weeks after planting does not support the use of 5–6 month CRF at the application rates used in this experiment with short-cycle plants such as bedding plants in compared to use of WSF. Except for the bottom placement treatment, the use of 8–9 month CRF resulted in generally less nutrients leached than WSF.
Nutrient Leaching from Container-Grown Ornamental Tree Production
Authors: Zhu H. , Zondag R.H. , Merrick J. , Demaline T. , Krause C.R.
Published: August 2020

Economical production of marketable container-grown ornamental shade trees with minimum amounts of nutrients in leachate requires careful management of fertilizer applications during a growing season. Sixteen fertilizer treatments were evaluated for their nutrient leaching potential in container-grown ‘Red Sunset’ red maple (Acer rubrum L.) production in a commercial nursery. Tests were conducted at two sites that were irrigated with either city or recycled pond water. Two slow-release granular fertilizers (18-5-12 and 12-0-42) were applied separately or together, by incorporation, top-dressed, or both, to trees grown in #7 containers and placed above or below ground. Trees irrigated with pond water also received supplemental liquid nutrients throughout the growing season along with nitric and phosphoric acids. Compared to either top-dressed or incorporation of fertilizer, incorporation of fertilizer combined with top-dressing doubled the amounts of nutrients applied but did not increase tree growth and caused greater nutrient leaching through the container substrate. Adding nitric and phosphoric acids to the supplemental liquid nutrients had little effect on lowering pH of the container substrate to the desired level. Trees irrigated with pond water had greater caliper growth than trees irrigated with city water, but this practice caused greater nutrient loss through the leachate and required additional nutrient inputs and labor throughout the growing season. Among the 16 fertilizer practices, the top-dressed fertilizer applications in the above- and below-ground containers were the most efficient method to produce fast tree growth with low nutrient leaching.
Responses of Six Lamiaceae Landscape Species to Saline Water Irrigation
Authors: Wu Shasha , Sun Youping , Niu Genhua , Pantoja Graciela Lizette Grimaldo , Rocha Arturo Castro
Published: August 2020

Salt tolerance of six Lamiaceae ornamental species was evaluated in a greenhouse experiment. Rooted cuttings were transplanted into 3.8 L (1 gal) pots and grown for three weeks in the greenhouse before treatment. Plants were then irrigated six times with a nutrient solution at an electrical conductivity (EC) of 1.2 dS·m−1 (control) or a saline solution at EC of 5.0 or 10.0 dS·m−1 (EC 5 or EC 10). Stachys coccinea (Texas betony) was the most salt tolerant among the six species tested, with less than 50% foliar damage and 56% reduction of dry weight (DW), and less than 10% reductions in gas exchange in EC 10 compared with nontreated plants. Perovskia atriplicifolia (Russian sage) and Lamium maculatum ‘Pink Pewter’ (spotted dead nettle) were moderately tolerant with slight salt damage and low mortality rates in EC 10. With visual scores of 3.1 and 3.9 (0 = dead; 5 = excellent), and DW reduction of 36 and 43% in EC 5, Russian sage and spotted dead nettle could grow well when irrigated with low quality water with EC less than 5.0 dS·m−1. Ajuga reptans ‘Burgundy Glow’ (bugleweed), Poliomintha longiflora (Mexican oregano), and Scutellaria suffrutescens ‘Pink Skullcap’ (cherry skullcap) were the most sensitive to salinity stress with a survival rate of 80% and 0 in EC 5 and EC 10, respectively.
Ex Vitro Rooting of American Chestnut Improves Acclimatization Survival and Plantlet Quality
Authors: Oakes Allison D , Desmarais Tyler R. , Powell William A. , Maynard Charles A.
Published: August 2020

Tissue culture of plants has many applications, from producing genetically identical horticultural varieties, to production of secondary metabolites, to virus indexing, and most relevantly, developing novel traits by genetic transformation. Using Agrobacterium-mediated transformation on somatic embryos, blight-resistant American chestnuts [Castanea dentata (Marsh.) Borkh.] have been developed as shoot cultures in plant tissue culture. Rooting tissue-cultured shoots and acclimatizing the rooted plantlets are key steps in tree production. In this study, in vitro and ex vitro rooting methods were compared. The ex vitro method resulted in a lower initial rooting percentage but an overall higher survival percentage, resulting in higher potted plant production. The higher survival was likely due to partial acclimatization taking place before the plantlets were transplanted into potting mix. After 8 weeks, plantlets rooted via the ex vitro method were taller, and had more, and larger, leaves than the in vitro-rooted plantlets. These trees are currently in high demand for inoculation studies for federal regulatory review and eventually for restoration of this keystone species to its native habitat.
Responses to Propagation Substrate and Rooting Hormone Products to Facilitate Asexual Propagation of Silene chalcedonica and Silene coronaria
Authors: Jiang Li , Dunn Bruce L. , Wang Yun-wen , Goad Carla L.
Published: August 2020

Many ornamentals are commercially propagated by cuttings, which is an easy and cost-effective propagation method. Silene L. is a promising genus for extensive use as a landscape ornamental due to its drought tolerance, profuse flowering, and perennial characteristic. Silene is readily cross pollinated, so to ensure genetic purity for breeding and cultivar release, an asexual cutting propagation protocol needs to be established. Adventitious rooting of cuttings of Silene chalcedonica (L.) E.H.L. Krause and Silene coronaria (L.) Clairv. were evaluated using two different propagation substrates and three different root-promoting hormone products. Rooting percentage of S. chalcedonica cuttings was improved by Dip ‘N’ Grow treatment (1,000 mg·L−1), which contains 1% indole-3-butyric acid and 0.5% 1-napthaleneacetic acid, and Hormex Rooting Powder No. 1 (1,000 mg·L−1), which contains 0.10% indole-3-butyric acid; however, 89% of S. coronaria cuttings rooted readily in vermiculite without an auxin treatment. Therefore, rooting success of stem cuttings was highly species related. Because of the relatively low rooting percentage seen in vermiculite (46%) and in perlite (63%) using Dip ’N Grow auxin treatment for S. chalcedonica, an effective stem cutting propagation method still needs to be explored for this species.
Less is More? Basil Growth and Flowering under Below-Recommended Nitrogen Fertilization Rates
Authors: Rhodes Stephanie A. , Chong Juang-Horng
Published: August 2020

Basil (Ocimum basilicum L.) is an herb commonly used as a flavoring additive for food. Its cultivation requires the selection of an adequate fertilization level that results in the greatest crop yield. This study evaluated the effects of four sub-recommended nitrogen fertilization levels [0, 21, 48 and 91 ppm N (mg·L−1 nitrogen)] on basil (cv. ‘Dark Opal’) growth, flower production, time of flowering, and leaf and stem N and C contents. The nitrogen fertilization level closest to the optimal rate (91 ppm N) produced plants with greater canopy weights, and more plants flowered than at the lower fertilization levels. However, plants fertilized at 21 ppm N were 14.7% taller and had about the same number of fully expanded leaves and branches, but with more flower clusters, than plants fertilized at 91 ppm N at 56 days after the initiation of the fertilization treatments. Growers may benefit from a lower-than-recommended nitrogen fertilization level (21 ppm N), which produced plants with more flowering clusters per flower head and with just as many leaves as higher nitrogen fertilization levels.
Attractiveness of Species of Vitex (Chastetree) to Pollinators
Authors: Hawkins Susan M. , Robacker Carol D.
Published: August 2020

Native and non-native bees are important pollinators of both food and ornamental crops. However, bee populations across the world have declined, mainly through loss of habitat. Careful selection of landscape plants in urban areas can help mitigate habitat loss and create new habitat for pollinators. Ten mature genotypes of Vitex, comprising V. agnus-castus L., V. negundo L., and a hybrid between V. agnus-castus x V. rotundifolia L. f., were evaluated during June and July 2016 to assess their attractiveness to pollinators. Pollinator counts were taken two times daily, at 9:00 a.m. and 11:00 a.m., twice weekly for three weeks. Pollinators were also captured from the Vitex plants for identification. Insects captured from Vitex plants were identified to genus and bumblebees [Bombus spp. (Latreille, 1802)] were further identified to species. Bumblebees and honeybees [Apis mellifera (Linnaeus, 1758)] were more numerous on Vitex plants than carpenter bees. V. agnus-castus plants attracted more bumblebees than honeybees. V. negundo and the V. agnus-castus x V. rotundifolia hybrid attracted more pollinators over the course of the study than V. agnus-castus. Our study shows that Vitex plants can be a good resource to support pollinators in an urban landscape.

Index words: urban landscape, bumblebees, honeybees; Vitex agnus-castus, Vitex negundo, Vitex rotundifolia.

Species used in study: Vitex agnus-castus L.; Vitex negundo L.; Vitex rotundifolia L.
Growth and Flowering of Salvia nemorosa ‘Ostfrieland' in Response to Reduced Irrigation1
Authors: Bayer Amanda
Published: August 2020

Reduced irrigation (RI) can conserve water and control plant growth; however, the timing of RI applications can impact plant growth and flowering. The goal of this research was to quantify growth of Salvia nemorosa L. ‘Ostfrieland' (East Friesland) in response to RI. A soil-moisture sensor automated irrigation system was used to apply four irrigation treatments: RI and well-watered (WW) controls (20% and 38% substrate water content) and two combination treatments to apply RI for either the first two weeks (20% followed by 38%, RIWW ) or final four weeks (38% followed by 20%, WWRI ) of the six-week study. Flower number, height, compactness, and relative chlorophyll content (SPAD) were not different across treatments. Average flower stem length was greater for the WW and RIWW treatments than for the RI treatment. Shoot dry weight was less for the RI treatment compared to the WW and RIWW treatments, respectively]. Cumulative irrigation volume was lowest for the RI treatment and highest for the RIWW treatment. Visually, plants in the RIWW treatment had an open, floppy habit that would likely negatively impact sales in a retail setting. Plants in the RI treatment were smaller, but visually appealing.

Index words: soil moisture sensor, plant production, herbaceous perennial, container plants.

Species used in this study: ‘Ostfrieland' salvia (Salvia nemorosa L.).
An Update of the Literature Supporting the Well-Being Benefits of Plants: Part 4 – Available Resources and Usage of Plant Benefits Information
Authors: Hall Charles R. , Knuth Melinda J.
Published: August 2020

This paper provides an overview of the key resources available to green industry firms that provide evidence of the health and well-being benefits associated with plants and improved landscaped areas and how they influence the physiological, psychological, cognitive, and social well-being constructs affecting quality of life. These benefits may persuade reluctant residential homeowners to purchase plants and improve their landscapes, may aid municipal leaders and policymakers in justifying green infrastructure-related funding decisions, and may provide grounds for the construction industry for using biophilic design principles to ensure the built environment offers opportunities for green space interactions. In this way, the green industry can play a pivotal role not only in providing plants of high quality for these applications, but in educating stakeholders regarding the benefits discussed herein. This research should also be strategically incorporated into both industry-wide and firm-specific marketing messages that highlight the quality of life value proposition in order to maintain the industry's sense of value and relevance to residential landscape consumers of the future. If done correctly, the demand for green industry products and services may be affected positively.

Index words: benefits of plants, information resources, elasticity of demand.
Effects of Container Size, Root Pruning, and Fertilization on Growth of Seedling Pecans
Authors: Keever G.J. , Cobb G.S. , McDaniel R.
Published: August 2020

Seedling pecan top growth was greater in 38 1(#10) containers and shallow 19 1(#5) containers when compared to deeper 19 1 (#5) containers and 11 1 (#3) containers; however, all trees were large enough to bud by July of the first growing season. Root pruning at transplanting did not affect top growth, but increased root branching and total root growth. Increased rates of a complete fertilizer increased root growth, but did not affect top growth.
Sod Marketing at the Consumer Level
Authors: Adrian John L. , Lokey Charles M. , Dickens Ray
Published: August 2020

Demand and consumption relationships for sod at the consumer level of the market were estimated. The price of sod, lot size and property value had significant impact on sod purchases. Consumers were responsive to sod price changes with a 1% change in price resulting in a 1.83% change in quantity demanded, other factors being held constant at mean levels. An evaluation of data for purchasers and nonpurchasers of sod indicated that income, house age, interest in landscaping and occupation had significant impact on purchases. Income elasticities for households having an annual income in excess of $31,000 were found to be elastic; that is, these households respond to income increases with larger purchases of sod. The market participation (entry-exit) phenomenon was credited with at least 70% of the total market adjustment by purchasers. These relationships emphasize the need for careful examination of advertising and pricing efforts of sod producing and marketing firms and also the potential growth of the industry as incomes and the general standard of living increase.
Effects of Seed Handling, Pre-germination and Planting Positions on Tree Seedling Root and Stem Development
Authors: Appleton B. L. , Whitcomb C. E. , Akers S. W.
Published: August 2020

Distortions of stem and root systems are sometimes noted with woody landscape plants propagated from seed. While position of the seed during stratification appears to produce no adverse effect, a change in seed orientation during pre-germination and/or transplanting can influence the subsequent development of these stem and root systems, frequently resulting in distorted seedlings unacceptable for commercial or research use.
Container Production of Comptie, Zamia furfuracea Ait.
Authors: Keever G.J. , Cobb G.S.
Published: August 2020

The effects of cultural factors on growth of comptie, Zamia furfuracea Ait., were evaluated. Plant growth was increased under 47% shade compared to 72% shade and when 1.2 kg m−3 (2 lb yd−3) dolomitic limestone was incorporated into the medium compared to 4.7 kg m−3 (8 lb yd−3). Nitrogen fertilization of 200 ppm and 300 ppm per week increased frond number compared to 100 ppm per week whereas container volume had no effect on plant growth.
Influence of Fertilizer Briquette Placement and Irrigation Regime on Container Medium Nutrient Content and Growth of ‘Mrs. G.G. Gerbing’ Azalea
Authors: Ingram Dewayne L. , Yeager Thomas H.
Published: August 2020

‘Mrs. G.G. Gerbing’ azaleas were grown for 1 year in a pine bark:Canadian peat:builders' sand (2:1:1 by vol) medium amended with 3 kg/m3 (5 lb/yd3) of dolomitic limestone and fertilized with 4 Woodace 14N-l.5P-2K (14-3-3) briquettes placed either below the root ball, 4 briquettes placed in the growth medium surface or 2 briquettes in the surface and 2 below the root ball. After one year, shoot and root dry weights were greatest for the surface placement and these plants were less chlorotic than for the other placements. The 460 ml (l in) per irrigation rate resulted in the smallest plants with more chlorosis than the 150 or 230 ml (0.3 and 0.5 in) rates. Leaf tissue, N, P and K levels were generally lower than optimal levels for azaleas. Data from this experiment indicate Woodace briquettes should be placed in the growth medium surface and the medium should be amended with supplemental micronutrients even though the briquettes contain micronutrients.
Effect of Vigorous Shoot-Tip-Removal on Increased Fruiting of Young ‘Western’ Pecan Trees
Authors: Hanna J. Dan
Published: August 2020

Tip removal pruning of long vigorous shoots of young ‘Western’ pecans, Carya illinoensis, (Wang) K. Koch, growing in the Rio Grande Valley in El Paso County, Texas, increased lateral buds persisting and growing through the season, decreased growth per lateral bud forced, and increased fruiting of shoots from buds forced from pruned shoots during both years. Total yield per tree was increased the second year. A useful role for tip-pruning in controlling vigor and converting vigorous shoot growth to fruiting shoots is indicated.
Effects of Three Herbicides on the Foliage of Kurume Azaleas
Authors: Frank J. Ray , Krause Charles R. , Edward Beste C.
Published: August 2020

A single foliar spray of Fusilade 2000 (fluazifop-butyl) [( ± )-2-[4-[[5-(trifluoromethyl)-2-pyridinyl] oxy] phenoxy] propanoic acid] or PP005 (fluazifop-p-butyl) [butyl (R)-2[4-[[5-(trifluoromethyl)-2-pyridinyl] oxy] phenoxy] propanoate] at 0.50 or 1.0 kg/ha (0.45 or 0.89 lb/A) caused extensive foliar damage and reduced growth of ‘Hinocrimson’ azaleas but not ‘Hershey Red.’ Poast (sethoxydim) [2-[1-(ethoxyimino)butyl]-5-[2-ethylthio)-propyl]-3-hydroxy-2-cyclohexen-l-one] at 1 kg/ha (0.89 lb/A) or less did not injure ‘Hinocrimson’ or ‘Hershey Red’ azaleas. Scanning electron microscopy observations and photographs of the upper leaf surface of the untreated control plants of both azalea varieties revealed that the epidermal cells were uniformly turgid and covered with smooth epicuticular wax. The leaf epidermal cells of ‘Hinocrimson’ azalea treated with Fusilade 2000 or PP005 at rates of 0.25 kg/ha (0.22 lb/A) or more were flaccid, the epicuticular wax was damaged, and the stomatal configurations were altered to produce cells with an ovoid pointed appearance. When ‘Hinocrimson’ foliage treated with Fusilade 2000 or PP005 was examined with energy dispersive X-ray analysis (EDX), a potassium (K) peak which was over 3 times higher than that of the untreated control plants was observed. No increase in potassium peak size was observed following EDX analysis with any ‘Hershey Red’ foliage samples.
The Effect of Light Quality and Fertility on Long Term Interior Maintenance of Selected Foliage Plants
Authors: Turner Melanie A. , Morgan David L. , Reed David Wm.
Published: August 2020

Ficus benjamina, F. stricta, Dieffenbachia amoena and Brassaia arboricola were used to determine the effects of light quality and fertility on long-term maintenance of foliage plants in low light. The following light regimes were tested to determine the effect of light quality: 1) 100% PAR (photosynthetically active radiation) from fluorescent, 2) 70% PAR from fluorescent plus 30% PAR from incandescent, and 3) 50% PAR from each of Gro-Lux and Gro-Lux Wide Spectrum fluorescent. All light intensities were standardized at a total of 20 uEm−2s−1 (149 ft-c) for 4 months then 14 uEm−2s−1 (104 ft-c) for 8 months. When total PAR was equalized between treatments, no light source consistently proved superior for maintenance of the plants for one year in the interior. Three fertilizer regimes were used to maintain the four species in the interior for three months at 20 uEm−2s−1 (149 ft-c) then for 9 months at 12 uEm−2s−1 (89 ft-c). The fertilizer regimes tested were 1) soluble fertilizer (Peter's 20-20-20) added wkly in the irrigation water weekly at 200 ppm N : 88 ppm P : 166 ppm K, 2) slow-release fertilizer (Osmocote 14-14-14, 3 month release) applied as a top dress every three months at 4.1 g/15 cm (6 in) pot (0.57 g N : 0.25 g P : 0.47 g K), and 3) an unfertilized control. At the end of one year the effects of fertilizer treatment were found to be minimal, with the soluble fertilizer treatment showing some improved response with several growth parameters.
Growth Response and Mineral Uptake of Vegetable Transplants Grown in a Composted Sewage Sludge Amended Medium.
Authors: Falahi-Ardakani A. , Bouwkamp J.C. , Gouin F.R. , Chaney R.L.
Published: August 2020

Six vegetable species, broccoli, cabbage, lettuce, eggplant, pepper, and tomato plants were grown for 8 wks on a medium of composted sewage sludge (compost), perlite, and peat (equal parts by volume). P, Ca, and Mg were adequate for the growing period, but accumulation of N and K did not increase after the 6th wk after transplanting. Cabbage and broccoli accumulated greater amounts of N and K from the medium and could be successfully grown in the medium without supplemental fertilization. Zn and Cd, potentially hazardous heavy metals present in compost, did not reach excessive levels for either plant nutrition or human consumption.
Tomato Spotted Wilt Virus Infection of Commercial Aphelandra sp.
Authors: Halliwell Robert S. , Barnes Larry W.
Published: August 2020

Tomato spotted wilt virus (TSWV) is becoming more prevalent in Texas crops. TSWV diseases are endemic in peanuts, tomatoes, peppers, and are becoming more of a problem in greenhouse crops. TSW of Aphelandra sp., is described as a new disease problem in commercial greenhouse production.
Occurrence of Thielaviopsis basicola and Phytopathogenic Nematodes on Healthy and Declining Landscape-Grown Ilex crenata ‘Helleri’
Authors: Wick Robert L.
Published: August 2020

Examination of the soil and root systems of 34 landscape-grown Japanese holly, (17 rated as healthy/17 as declining) was undertaken to determine the role of Thielaviopsis basicola and phytopathogenic nematodes in plant decline. One hundred roots per plant were cultured on carrot discs and the recovery of T. basicola was recorded. Soil was assayed for phytopathogenic nematodes and tested for P, K, Ca, Mg, soluble salts and pH. Thielaviopsis basicola was found to have colonized 33 of the 34 plants and the extent of occurrence was positively correlated with the presence of decline symptoms. Declining plants had a total of 34% of intact roots colonized while healthy plants had 17%. Only one plant had a significantly high number of nematodes. Nematodes, soil pH, soluble salts, P, K, Ca, and Mg were not correlated with decline.
Suitability of Thirteen Different Host Species for Elm Leaf Beetle, Xanthogaleruca luteola (Coleoptera: Chrysomelidae)
Authors: Hall Richard W. , Townsend Alden M. , Barger Jack H.
Published: August 2020

Thirteen different host species for elm leaf beetle, Xanthogaleruca luteola (Muller), were assayed to determine their relative suitability. Species examined were Ulmus parvifolia Jacq., U. thomasii Sarg., U. laevis Pall., U. wilsoniana Schneid., U. americana L., U. japonica Sarg., U. pumila L., U. rubra Muhl., U. laciniata Mayr., U. glabra Huds., U. carpinifolia Gledisch, Zelkova serrata Makino, and ‘204,’ a hybrid of U. carpinifolia × U. parvifolia. Suitability was determined by feeding adults excised foliage from a tree and measuring mortality and fecundity during a two wk period. Significant differences in beetle mortality and fecundity occurred among hosts. In general, European elms were better hosts than American or Asiatic species. Suitability of a European x Asiatic hybrid fell between that of the parent species.
Response of 13 Species of Landscape Plants to Altered Photoperiods
Authors: Keever Gary J. , Cobb Gary S.
Published: August 2020

Thirteen species of temperate landscape trees and shrubs grown outdoors in Mobile, Alabama from March 26, 1985, until June 5, 1986, were exposed to natural (NP), night interrupted (NI), or extended (EP) photopenods from June 21 until November 15. Shoot growth measured in December varied among species but was either greater under long day conditions or similar to growth under NP, whereas root development was greater with NP or unaffected by photoperiod. By June 1986 shoot growth was either greater under NP or similar to growth under EP or NI. Root growth patterns were similar to those observed in December. Six species exposed to long day conditions exhibited extensive twig dieback, following subfreezing winter temperatures.
Evaluation of European Corn Borer Resistance in Hardy Chrysanthemum
Authors: Schultz P. B. , Coffelt M. A.
Published: August 2020

Resistance of 12 yellow and 12 bronze chrysanthemum cultivars to the European com borer, Ostrinia nubilalis (Hubner), was evaluated in laboratory studies. Yellow cultivars ‘Freedom’, ‘Classic’, ‘Compatriot’, and ‘Fortune’ and bronze cultivar ‘Pancho’ had significantly lower infestation percentages. In field monitoring of chrysanthemum grown in commercial nurseries, the cultivar ‘Fireside Cushion’ was significantly lower at both nurseries, with cultivars ‘Buckeye’, ‘Grenadine’, and ‘Viking’ also having significantly lower infestation percentages. A significant positive correlation between infestation levels and stem diameters indicated stem thickness may be an indicator of host plant resistance.
Relative Growth Rate and Plant Habit of Linden Taxa
Authors: Pellett H. , Vogel K. , McNamara S. , Zuzek K.
Published: August 2020

Many cultivars of Tilia cordata Mill. and other Linden taxa have been evaluated at the University of Minnesota Landscape Arboretum. This paper provides data on relative growth rate and photographs illustrating differences in plant habit.
Influence of Nitrogen and Phosphorus on Growth and Tissue N and P Concentration in Salvia greggii
Authors: Hipp Billy W. , Simpson Benny J. , Graff Paul S.
Published: August 2020

Studies were conducted at the Texas Agricultural Experiment Station, Dallas to determine nitrogen and phosphorus requirements of Salvia greggii Gray. (autumn sage), a resource-efficient landscape plant for the Southwest. Maximum growth of potted rooted cuttings used in the studies was obtained with application of 200 mg/liter (ppm) N and 50 mg/liter (ppnl) P, although fertilization with 150 mg/liter (ppm) N and 30 mg/liter (ppm) P would produce near maximum growth. Tissue levels should be > 2.2% N and > 0.20% P for these elements not to limit growth.
Interior Performance of Temperate Zone Landscape Plants
Authors: Keever G.J. , Cobb G.S. , Stephenson J.C.
Published: August 2020

Cleyera (Ternstroemia gymnanthera), spreading lilyturf (Liriope spicata), Southern magnolia (Magnolia grandiflora), heavenly bamboo (Nandina domestica), mondo grass (Ophiopogon japonicus), climbing fig (Ficus pumila), and variegated waxleaf privet (Ligustrum japonicum ‘Variegatum ’) grown under 3 production light levels and shade-grown golden Japanese euonymus (Euonymus japonica ‘Aureomarginata’), plantain lily (Hosta ventricosa), King's Ransom Oregon grapeholly (Mahonia aquifolium ‘King' Ransom’), dwarf gold-dust plant (Aucuba japonica ‘Variegata Nana’), Wood's Dwarf heavenly bamboo (Nandina domestica ‘Wood's Dwarf’), Japanese anise-tree (Illicium parviflorum), and Pink Lady Indian hawthorn (Raphiolepis indica ‘Pink Lady’) adapted well to interior conditions following productlon. Bugleweed (Ajuga reptans) and variegated wintercreeper euonymus (Euonymus fortunei ‘Varietgata’) grown under 64% light exclusion were of acceptable quality while plants grown in full sun and under 47% light exclusion were of poor quality. Quality of Wintergreen Korean boxwood (Buxus microphylla koreana ‘Wintergreen’) grown under all production light levels was unacceptable after 15 weeks in the interior environment.
Influence of Gibberellins4 + 7 on Germination of Fraser Fir
Authors: Henry Paul H. , Blazich Frank A.
Published: August 2020

Seeds of Fraser fir [Abies fraseri (Pursh) Poir.] were soaked in solutions of gibberellins4+7 (GA4+7) at concentrations of 0, 400, 500, 600, 700, 800, 900, and 1000 ppm. Following treatment, seeds were germinated in the presence and absence of light at 9/15 hr thermoperiods of 30°/20°C (86°/68°F) and 20°/10°C (68°/50°F). At 30°/20°C (86°/68°F), 42-day germination of seeds maintained in darkness was significantly increased at GA4+7 concentrations of 500 and 600 ppm. Stimulation was not noted for illuminated seeds at 30°/20°C (86°/68°F) or for seeds germinated at 20°/10°C (68°/50°F).
Influence of High Salt Levels on the Germination and Growth of Five Potentially Utilizable Plants for Median Turfing in Northern Climates
Authors: St-Arnaud M. , Vincent G.
Published: August 2020

We evaluated the germination and growth of Coronilla varia (crown vetch), Lotus corniculatus (birdsfoot trefoil), Medicago lupulina (black medic), Kochia scoparia (kochia) and Polygonum aviculare (prostrate knotweed) at different NaCl concentrations. No reduction of germination was observed in the five species studied for all concentrations of NaCl. High concentrations of NaCl in the soil adversely affected the growth of L. corniculatus and M. lupulina, but not of the other species. For P. aviculare, germination and growth was better with higher salt concentrations.