bluuebunny/crossref_metadata_2025 huggingface dataset:
Influencing Public Perception of Sustainable Roadside Vegetation Management Strategies
Authors: Lucey Anne , Barton Susan
Published: August 2020

Sustainably managed roadsides limit non-native turf grass and include meadows of native warm season grasses and flowering perennials, native shrubs, and trees. Implementation of sustainable strategies result in cost savings, better water quality and infiltration, increased diversity of insect life and benefits to the socioeconomic health of the state. Lacking an awareness of associated benefits, the public is often hesitant to accept sustainable, but less manicured roadsides, causing many Departments of Transportation to revert to traditional management regimes. This research assessed perception and determined that acceptance could be increased with an awareness of associated benefits. An Internet survey was administered to three groups of participants. A control group rated eleven roadside images from least to most desirable and completed a brief survey. An experimental group read a list of information about traditional and sustainable strategies of roadside vegetation management before rating the images and completing the survey. Another experimental group viewed a 6½ minute video that delivered the same information as the list, but engaged the respondent differently. This group then rated the images and completed the survey, as did the previous two groups. Among those who read the list, a significant change in perception occurred for three of the images when compared to those in the control group. Among those who viewed the video, a significant change in perception occurred for four of the images when compared to those in the control group. When all images were compared to the baseline image (mown turf), Delaware's current default vegetation management strategy, each response distribution was significantly different than that of mown turf. Respondents rated images of flowering meadows, meadow with a mown turf margin, turf with a wooded edge, shrubs and trees more desirable than mown turf and images with grassy meadows less desirable. When strategies were grouped according to similar attributes and compared to mown turf, respondents rated images with flowers (flowering meadows, shrubs and trees), and images with a mown turf margin more desirable than turf and grass meadows less desirable.
Reduced Use of Pesticides for Effective Controls of Arthropod Pests and Plant Diseases
Authors: Zhu Heping , Zondag Randall H. , Krause Charles R. , Merrick Jim , Daley Jay
Published: August 2020

Current label recommendations of pesticides for arthropod pests and plant diseases in the nursery and green industry are vague and frequently result in excessive pesticide use. The objective of this research was to demonstrate that modifications of spray application techniques with current spray equipment in ornamental nursery production could reduce pesticide use. The efficacy of half rates and full rates of both active ingredients and carrier was investigated in commercial nurseries with air-assisted sprayers in two tests and a state inspector survey for the control of arthropod pests and plant diseases. Sprayers were optimized with properly sized nozzles and properly calibrated operating parameters. In Test 1, treatments were conducted in approximately 0.5 ha (1.2 A) plot each in three commercial nurseries for control of arthropod pests and diseases, and in Test 2, the same treatment for aphid control was evaluated in a birch tree plot. The survey was a compilation of the pests and diseases that were diagnosed by state inspectors in over 2,800 plant varieties and species from two commercial nursery fields [total about 280 ha (692 A)] after the spray treatments in six growing seasons. Crop damage by 49 insects and 40 diseases were surveyed for different application rates. The studies revealed that insect and disease control using 50% of the label rates was as effective as full rates when quality spray coverage on targets was achieved, resulting in real cost benefits to producers, consumers and the environment.
Low-Value Trees as Alternative Substrates in Greenhouse Production of Three Annual Species
Authors: Murphy Anna-Marie , Gilliam Charles H. , Fain Glenn B. , Allen Torbert H. , Gallagher Thomas V. , Sibley Jeff L. , Boyer Cheryl R.
Published: August 2020

Peat and perlite have served as industry standards in greenhouse substrates for over 50 years. The continued availability of peat, paralleled with its inert characteristics, as well as its ability to stay generally pathogen-free have all contributed to its success in the horticulture industry. Expanded perlite has long been used as an amendment in container mediums to provide air space to container substrates without adding to bulk density or affecting substrate pH and EC. However, due to increased restrictions on the harvesting of peat, as well as fluctuations in fuel prices necessary for shipping, the future availability of peat is a largely unknown factor in greenhouse production. Additionally, growers consider perlite to be a general nuisance due to the lung and eye irritation problems. Because of these problems, researchers have focused on identifying and evaluating possible alternatives to standard substrates. These studies evaluated three possible substrate alternatives for use in greenhouse production, including fresh sweetgum (SG), hickory (H), and eastern redcedar (RC), in addition to WholeTree (WT) substrate. Three greenhouse annual crops (petunia, impatiens, and vinca) were planted in varying ratios of these species mixed with peat. Plants grown with SG and H as amendments did not perform as well as a traditional peat:perlite mix with respect to flower number, growth indices, and plant dry weight. However, plants grown in RC tended to be equivalent to those grown in a traditional mix. Data showed that greenhouse producers could amend their standard greenhouse substrate with up to 50% eastern redcedar with little to no differences in plant growth.
Using Simple Sequence Repeats (SSRs) to Measure Pollen Flow in a Flowering Dogwood Orchard
Authors: Rhoades Paul , Wadl Phillip A. , Klingeman William E. , Trigiano Robert N. , Skinner John
Published: August 2020

Dispersal of flowering dogwood pollen in an orchard was evaluated by performing parentage analyses on open pollinated seedlings collected from a single maternal tree. Pollen sources for 45 seedling trees were established using three polymorphic simple sequence repeat (SSR) loci. Previous data suggest that Cornus florida pollen is typically limited to travel between closely situated trees. If this is true, breeding may be simplified by crossing trees through open pollination rather than more laborious current methods involving pollination cages. However, the expected leptokurtic distribution, in which the likelihood that pollen transfer will occur between trees decreases quickly as distance increases, was not seen. Although the majority of paternal trees were located within the 12 m (39.4 ft) radius of the study area, the trees most likely to have donated pollen were some of those located the greatest distance from the mother tree. Unusual pollen movement may be explained, in part, by asynchronous flowering times of trees within the study or by genetic similarities exhibited between the mother tree and potential pollen donors in the area. Additionally, andrenid and halictid bees, which were the predominant pollinators observed at this site, may have moved pollen farther than expected.
Management of Powdery Mildew on Flowering Dogwood with Soybean Oil
Authors: Deyton Dennis E. , Sams Carl E. , Cannon Adrianna L. , Cummins John C. , Windham Mark T.
Published: August 2020

Soybean oil formulations developed in our laboratory were evaluated for control of powdery mildew on flowering dogwood Cornus florida. In a preliminary trial in a field nursery, two formulations, TNsoy1 and TNsoy2 [0, 1 or 2% (v/v)], were applied to field-grown flowering dogwood at 2 wk intervals from June 10 until August 19. Soy oil-treated trees had less powdery mildew, higher net photosynthetic rate and growth rate than unsprayed trees, without apparent phytotoxicity. Leaves sprayed with Banner MAXX had less powdery mildew and higher photosynthetic rates than oil treated leaves. These same treatments applied the next year under more frequent rain showers did not provide satisfactory control. Newer soybean oil formulations using natural or food grade emulsifiers, were compared to three commercial botanical oil formulations and to SunSpray Ultra Fine Oil in greenhouse trials. All oil formulations provided some protective and eradicative control of powdery mildew. Photosynthesis of oil treated leaves was usually depressed, compared to controls, for several days but recovered. In greenhouse trials where the oil was not washed off by rain or irrigation, the oil residue was visible on leaves, reduced powdery mildew severity, and depressed photosynthesis for several weeks. In a second greenhouse trial, soybean oil formulations provided greater control if applied after rather than before initial inoculation.
Nitrogen Form Affects pH and EC of Whole Pine Tree Substrate and Growth of Petunia
Authors: Witcher Anthony L. , Fain Glenn B. , Blythe Eugene K. , Pounders Cecil T.
Published: August 2020

Wood-based substrates are potential alternatives or amendments to traditional peat-based and pine bark substrates. Undesirable changes in substrate pH may result from the application of supplemental fertilizer required by some crops grown in wood-based substrates. Experiments were conducted to evaluate petunia growth and substrate pH in response to nitrogen (N) treatments applied as a nutrient solution to whole pine tree (WPT) and peat-lite (PL) substrates. Nitrogen treatments were applied as 100% ammonium (NH4+ N), 100% nitrate (NO3−N), or a combination of both in various proportions. The pH range of WPT substrate widened considerably over time among the N treatments, while a change in substrate pH was minimal for PL substrate during the same period. Generally, 100% NO3−N and 100% NH4+ N resulted in the highest and lowest substrate pH, respectively, regardless of substrate. Greater shoot dry mass was obtained in PL substrates compared with WPT substrates. Maximum shoot dry mass and flower count with ‘Celebrity Rose’ petunia were obtained with the mixed N-form treatments in both substrates. Greater substrate air space and total porosity was associated with WPT substrates compared with PL substrates, the latter having greater container capacity.
Occurrence of Cercospora Blight on Cryptomeria japonica (L.f.) D. Don in the United States
Authors: Wick R.L. , Lambe R.C.
Published: August 2020

This is the first report of the occurrence of Cercospora sequoiae as a pathogen of Cryptomeria japonica in the United States. Koch's postulates were fulfilled on rooted cuttings indoors; the fungus caused dark brown lesions on succulent needles and stems. Conidiophores were fascicled and measured 40-107 μm. Conidia were brown, 33–80 μm × 4–6 μm, echinulate and 3–8 septate.
Control of Pratylenchus vulnus on American Boxwood
Authors: Hagan Austin , Gilliam Charles
Published: August 2020

Post-plant applications of Nemacur 15G, Vydate 10G, Furadan 10G, and Temik 15G controlled lesion nematode, Pratylenchus vulnus, on roots of Amencan boxwood. Combination of fall and spring nematode applications provided season long nematode control. One year after application, significant increases in shoot numbers and plant growth occurred with treated plants compared to nontreated plants.
Influence of Photoperiod and Minimum Overwintering Temperature on Growth of Nursery Liners
Authors: Daggett Carol , Klingaman Gerald L.
Published: August 2020

Ten woody plant species were rooted during the summer with half of each species overwintered at 4°C (40°F) and half at 18°C (65°F) minimum night temperature. Half of the plants in each temperature regime received long day conditions while half received short day conditions. By May 1 all species except Snow azalea (Rhododendron obtusum ‘Snow’), Emerald'n Gold euonymus (Euonymus fortunei ‘Emerald 'n Gold’), and deutzia (Deutzia gracilis) had greater dry weights with the 18°C (65°F) long day regime. Deutzia was heavier under the 4°C (40°F) regime with no difference between photoperiod treatments. At 4°C (40°F) only Judd viburnum (Viburnum x juddii) was heavier with the long day regime. Plants grown until June 1, after two flushes of vegetative growth, showed less overwintering treatment effect, but Hetzi holly (Ilex crenata ‘Hetzi’), blue rug juniper (Juniperus horizontalis ‘Wiltoni’), crapemyrtle (Lagerstroemia indica ‘Centennial’), and Judd viburnum (Viburnum x juddii) were larger when grown under the 18°C (65°F) long day regime.
Innovations and the Nursery Industry1
Authors: Whitcomb Carl E.
Published: August 2020

Two container designs are described that stimulate root branching and prevent root circling during production of nursery crops. In addition, the containers described accelerate the establishment of plants in the landscape and reduce losses. A pallet handling-overwintering-summer temperature modification system is described. This work unit solves several major problems related to container plant production. A root control system for growing nursery crops in the field is presented. This unique fabric container restricts root growth horizontally, but stimulates root branching and carbohydrate accumulation within the root system, thereby allowing transplanting any time and with little plant stress.
Adventitious Root Formation in Rosa Multiflora ‘Brooks 56’ Hardwood Cuttings
Authors: Davies F.T.
Published: August 2020

Production of Texas field grown rose bushes is inefficient with less than 60 percent of Rosa multiflora hardwood cuttings developing into marketable plants after two years of commercial production. Uniformity of rooting of hardwood cuttings differs between field location and time of year. Treatments consisting of Hare's powder, 0, 3000, 10000 mg/l IBA (0, 300, 10000 ppm), 2N H2SO4 acid treatment, NaOH solution pH 10.5 and/or wounding were established to test the effect of selected chemical and mechanical treatments on rooting hardwood Rosa multiflora cuttings propagated under field and greenhouse conditions. Results were comparable between field and greenhouse propagated hardwood cuttings. Best treatments were with Hare's powder and wounding, while acid, base and IBA treatments did not enhance rooting. The importance of determining the physiological condition of field stock plants for successful rooting of hardwood cuttings is discussed.
Effect of Pine Bark Age, Starter Nitrogen, and Activated Charcoal on Growth of Plants in Containers
Authors: Whitcomb C.E. , Appleton B.L.
Published: August 2020

Activated charcoal and soluble starter nitrogen were added to fresh and aged pine bark prior to use as a container growth medium. All test plants grew equally well in either fresh or aged pine, regardless of activated charcoal or soluble starter nitrogen application.
Influence of Liming Rate on Phosphorus Leaching from a Peat-Sand Medium
Authors: Havis John R. , Baker John H.
Published: August 2020

Leaching of phosphorus (P) from a peat-sand medium was measured at 3 liming rates. Leaching of P from superphosphate was reduced only at the highest rate of hydrated lime, 2.65 kg/m3 (4.5 lb/yd3), which resulted in pH 6.6. Each rate of lime reduced P leaching from the slightly soluble dicalcium phosphate. Further investigation of sparingly soluble P sources for amending soilless media is suggested.
Effect of Seedling Size and Transplant Bed Density on Performance of Eastern Hemlock Planting Stock
Authors: Eric Hinesley L.
Published: August 2020

After grading two-year-old Eastern hemlock (Tsuga canadensis (L.) Carr.) seedlings by height, performance was examined for one year under various transplant bed densities, and for 2 years in the field. In the nursery, average diameter growth and dry matter production were influenced by bed density; height growth was not. A transplant bed density of 65 plants/m2 (6/ft2) resulted in the greatest average diameter and dry weight, but densities up to 151 plants/m2 (14/ft2) yielded more usable transplants per unit of nursery bed. Although there were residual effects of transplant bed density, the major differences in growth after 2 growing seasons in the field were due to initial seedling size. Transplants originating from large seedlings outperformed those from small seedlings. Compared to small seedlings, larger plants require less time in transplant beds, are less troublesome to maintain in the field, and reach marketable size in fewer years, all of which increase their value relative to small seedlings.
Effects of Glomus fasciculatum or Glomus mosseae on Growth of Liriodendron tulipifera under High Fertility
Authors: Verkade Stephen D. , Hamilton David F.
Published: August 2020

Liriodendron tulipifera L. seedlings were grown under greenhouse conditions and inoculated with the endomycorrhizal fungi Glomus fasciculatum (Thaxter) Gerdemann & Trappe or G. mosseae (Thaxter) Gerdemann & Trappe. Inoculated and non-inoculated plants were grown in highly fertile medium of perlite : sphagnum peat moss : loam soil (2:2: 1, by volume with 120 mg/l NO3, 53 mg/l P, 130 mg/l K, and 12 mg/l NH4) and were watered as needed with nutrient solution (516.6 mg/l KNO3, 367.6 mg/l NH4NO3, and 0.124 ml/1 of 75% H3PO4). Both fungal species successfully promoted plant growth under these conditions, but G. mosseae tended to be more effective at promoting growth.
Container Production of Tropical Trees Using Sewage Effluent, Incinerator Ash and Sludge Compost
Authors: Fitzpatrick George
Published: August 2020

Five species of tropical trees, West Indian mahogany [Swietenia mahagoni (L.) Jacq.], Key lime [Citrus aurantiifolia (Christm.) Swingle], schefflera (Brassaia actinophylla Endl.), pink tabebuia [Tabebuia pallida (Lindl.) Miers], and pigeon plum (Coccoloba diversifolia Jacq.) were grown for 17 months in 50 cm (20 in) diameter galvanized steel containers (20 gal), with 2 potting media: a 4:1 (v:v) blend of sewage sludge compost: sifted incinerator ash; and a mix of 3:3:2:2:1 (v:v:v:v:v) cypress shavings: perlite: Canadian peat: muck (“Florida peat”): sand (commercial mix). Plants were irrigated with either tap water or secondary treated sewage effluent supplied by a low volume drip system. Schefflera grew faster in the commercial mix irrigated with tap water. The remaining 4 species grew equally as well in the sludge compost: ash medium irrigated with effluent, as they did in the commercial mix irrigated with tap water.
Effects of Soil Type and Compaction on the Growth of Ailanthus altissima Seedlings
Authors: Pan Elizabeth , Bassuk Nina
Published: August 2020

Ailanthus altissima (Tree-of-Heaven) seedlings were grown in compacted and non-compacted mason sand and sandy loam soil. Shoots and roots were measured to characterize seedling development and response to soil compaction. Dry weight increases were shifted to lateral roots when Ailanthus tap root growth was curtailed and relative growth rate slowed in response to changes in soil type and compaction. Although total plant dry weights were 50% lower in seedlings grown in compacted soils, increases in dry weights continued to the end of the experimental period.
Rooting of Pachysandra terminalis and Euonymus kiautschovica Stem Cuttings Under Intermittent Mist and Outdoor Thermo-blanket Tents
Authors: Lewandowski R.J. , Gouin F.R.
Published: August 2020

Thermo-blanket tent, intermittent mist propagation and copolymer moisture barrier systems were compared for rooting using common pachysandra (P. terminalis Sieb. & Zucc.), variegated pachysandra (P. terminalis ‘Variegata’), and euonymus (E. kiautschovica Loes.). Percent rooting and root dry weight of both pachysandra cultivars were higher under intermittent mist. More variegated pachysandra rooted than common pachysandra under both propagation systems. Measurements of root development over a 6 week period under both propagation systems indicated that euonymus cuttings rooted more rapidly under intermittent mist than under thermo-blankets; however, cuttings rooted 100 percent under both systems. Copolymer moisture barriers beneath thermo-blankets had no effect on percent rooting or root dry weight of euonymus cuttings.
Hydrophylic Polymers as a Carrier for VA Mycorrhizal Inoculum
Authors: Johnson C.R. , Hummel R.L.
Published: August 2020

Four techniques of inoculating rooted Carissa grandiflora cuttings with the mycorrhizal fungus Glomus intraradices were evaluated. Placement of a root inoculum around the root systems of Carissa or totally incorporated into potting medium resulted in higher colonization levels than dipping cutting root systems in suspensions of inoculum in Viterra or Terrasorb hydrophyllic polymers. Growth responses, especially top dry weight, showed little difference among the inoculation techniques. Mycorrhizal mediated growth benefits for the tops were realized for all treatments. Storage of root inoculum for 12 weeks at 4.4°C (40 °F) had little effect on colonization levels by the fungus in Carissa roots.
Vacuum Infiltration of Gibberellic Acid Stimulates Germination of Dormant Black Walnut Seeds
Authors: Dorn Christopher M. , Mudge Kenneth W.
Published: August 2020

Black walnut (Juglans nigra L.) seed normally requires cold stratification to overcome dormancy. In 2 experiments, dormant, unstratified seeds were treated with gibberellic acid (GA3) in attempts to overcome dormancy. To facilitate uptake of treatment solutions, seeds were scarified by making 2 small notches through the shell with a grinding wheel. Treatment solutions of 0, 50, 150, or 250 mg/l (ppm) GA3 were applied either by soaking seeds for 24 hours or by vacuum infiltration (VI) for 30 minutes. VI GA3 stimulated germination in both experiments to a level equal to or greater than germination of seeds receiving cold-moist stratification for 45 days. A brief 15 day stratification period followed by GA3 was more effective than VI alone. Soaking in GA3 was effective in the first experiment but not the second. Germination rate and seedling height was increased by GA3.
Growth Response of Photinia and Thuja and Nutrient Concentration in Tissues and Potting Medium as Influenced by Composted Sewage Sludge, Peat, Bark and Sawdust in Potting Media
Authors: Ticknor R.L. , Hemphill D.D. , Flower D.J.
Published: August 2020

Composted sewage sludge was blended with pumice and either bark, peat moss, or sawdust to form 6 potting media. Increasing the proportion of compost in media from 25 to 50% caused increased initial pH, electrical conductivity (EC), and airfilled pore space (AS) in all media, and increased growth of Photinia x fraseri Dress. and Thuja occidentalis L. ‘Pyramidalis.’ Sawdust-containing media had the highest pH, EC, and AS; sphagnum peat-containing media the highest water holding capacity and greatest shrinkage; bark-based media the highest bulk density. Plant growth in compost-based media containing peat or bark was equal to or better than that in two commercial media composed primarily of bark or peat.
Physical Properties of Pine Bark and Hardwood Bark Media and Their Effects with 4 Fertilizers on Growth of llex x ‘Nellie R. Stevens’ Holly
Authors: Bilderback T.E.
Published: August 2020

Pine bark (PB) and composted hardwood bark (HWB) were combined into 5 media. Particle size distribution, total porosity, air space, moisture retention characteristics, and bulk density were determined for each medium. Four commercial fertilizers were applied and substrate nitrogen levels, pH, % foliar nitrogen and top dry weight were determined for Ilex x ‘Nellie R. Stevens’ holly. Pine bark had approximately 84% of the particles between 4.75 and 1.0 mm (0.19 and 0.04 in). As HWB was added in 25% increments (by vol) the percent weight of particles in this range decreased. HWB increased bulk density, but did not significantly change total porosity. Hardwood bark and the 1:3 PB:HWB (v/v) medium held more water than other media. Nursery Special raised pH in all media treatments. Plants treated with SulfurKote tended to have the highest foliar nitrogen content. The Sierrablen in PB and SulfurKote in 3 PB:1 HWB and 1 PB:1 HWB (v/v) and HWB produced the greatest top dry weight.
Suitability of Whole Pine Tree Substrates for Seed Propagation
Authors: Witcher Anthony L. , Blythe Eugene K. , Fain Glenn B. , Curry Kenneth J.
Published: August 2020

Wood-based substrates are a viable option for producing crops in containers, but seed propagation in such substrates has not been sufficiently examined. Seed germination and seedling development in processed whole pine tree (Pinus taeda L.) substrates were evaluated using the Phytotoxkit and seedling growth tests. Substrates compared using the Phytotoxkit included a reference soil, aged (WPTA) and fresh (WPTF) whole pine tree, aged (PNA) and fresh (PNF) pine needles, pine bark (PB), peat moss (PM), and saline pine bark (SPB). Substrates evaluated using the seedling growth test included WPTA, WPTF, PB, and a peat-lite (PL) substrate. Seed germination percentage and total root length were evaluated for garden cress (Lepidium sativum L.), white mustard (Sinapis alba L.), and sorghum [Sorghum bicolor (L.) Moench] in repeated Phytotoxkit experiments (2010 and 2011). Seed germination percentage was lowest for garden cress in PNF, but similar among all substrates for white mustard and sorghum. Total root length was similar or greater in WPTA compared with PM for all species. Seedling emergence percentage and total root length were evaluated for lettuce (Lactuca sativa L.), tomato (Solanum lycopersicum L.), and oat (Avena sativa L.) in repeated seedling growth experiments (2010 and 2011). Seedling emergence percentage varied among substrates and was substantially greater in PL and WPTA compared with PB and WPTF in 2010. Total root length was greatest in PL compared to the other substrates for all species in both years. In addition, PL had significantly lower air space and greater container capacity compared with the other substrates.
Blueberry Culture and Pest, Disease, and Abiotic Disorder Management during Nursery Production in the Southeastern U.S.: A Review
Authors: Fulcher Amy , Gauthier Nicole Ward , Klingeman William E. , Hale Frank , White Sarah A.
Published: August 2020

The genus Vaccinium represents an increasingly important group of plants for the U.S. green industry. In 2012, blueberries (Vaccinium sp.) ranked the second most important berry crop in the U.S. with a total crop value over $780 million. The popularity of blueberries creates opportunities as well as challenges for nursery crop producers. This article presents a review of current nursery production practices of blueberry and explores the challenges and opportunities for nursery crop producers, including pesticide use during nursery production of an edible crop, and discusses current research relevant to the green industry. Needs for additional research and opportunities for breeding are presented. Blueberries are Ericaceous plants and have very specific cultural requirements. This review presents the culture, as well as insect, mite, and disease control from an integrated pest management (IPM) approach for several blueberry species. A serious threat to the blueberry market, spotted wing drosophila (Drosophila suzukii Matsumura) is discussed to provide information needed by commercial producers and landscape managers to address client and customer questions. This review also highlights the most relevant blueberry selections for container production in the southeastern United States.
Seedling Developmental Stage at Transplanting Affects Growth and Flowering of Medallion Flower and Globe Amaranth
Authors: Keever G.J. , Kessler J.R. , Fain G.B. , Mitchell D.C.
Published: August 2020

A study was conducted to determine how seedling development stage at transplanting from plug flats into small pots affected growth and flowering of two commonly grown bedding plants. Seeds of Showstar® medallion flower and ‘Las Vegas Pink’ globe amaranth were sown in 392-cell flats on five dates for each of two experimental runs before transplanting into 8.9 cm (3.5 in) cubic pots. At transplanting of both species, plant height, node count and shoot dry weight increased as days from sowing to transplanting increased and there was no visible cessation in shoot growth due to root restriction. Time to first flower from transplanting decreased linearly with both species in both runs, except with medallion flower in the second run, as time from sowing to transplanting increased. In contrast, time to flower of both species from sowing increased linearly as time from sowing to transplanting increased. However, the magnitude of the increase or decrease in time to flower differed between the two runs indicating that other factors, most likely light intensity and duration, besides node counts were affecting time to flower. Globe amaranth height and growth index and medallion flower growth index at first flower decreased as time from sowing to transplanting increased, whereas medallion flower height was not affected by time from sowing to transplanting.
Garden Consumers' Behavior and Attitudes Toward Woody Plants and Water Conservation in Two Selected Communities
Authors: King Andrew R. , Palma Marco A. , Behe Bridget K. , Fernandez R. Thomas , Sage Lynnell , Hall Charles R. , Arnold Michael A.
Published: August 2020

Sustainability is one of the most important topics facing today's Green Industry. Consumers are increasingly savvy, but previous studies have shown some misperceptions concerning new terminology in the agricultural lexicon. With the recent focus on water issues in large portions of the United States, water conservation is a facet of sustainability that is at the forefront. Previous research has shown that consumers of ornamental horticulture products value energy-saving production practices over those that conserve water, but that could change as water becomes more of a concern. The objective of this study was to determine the attitudes and behaviors of different consumer segments (based on previous plant purchases) concerning water conservation and to identify patterns for each segment. An in-person survey was administered to 108 participants in East Lansing, MI, and College Station, TX, in May of 2013. Participants were asked to provide demographic information, details about plant and garden supply purchasing history and attitudes and behavior toward water conservation and woody plant production. Eight segments were identified through cluster analysis based on previous plant purchases. Clusters included ‘avid plant purchasers’, ‘tree purchasers’, ‘intermediate plant purchasers’, ‘culinary plant purchasers’, ‘indoor plant purchasers’, ‘flowering perennial purchasers’, ‘herb plant purchasers’ and ‘non-plant purchasers’. Attitudes toward water conservation and woody plant production were relatively homogenous though general patterns did emerge. ‘Avid plant purchasers’ expressed a high level of interest (4.1/5) in woody plants while ‘non-plant purchasers’ were least interested (1.6/5). Attitudes toward water conservation were statistically similar (P ≤ 0.05) among all segments except for ‘culinary plant purchasers’ who expressed greater knowledge (3.4/5) and ‘non-plant purchasers’ who expressed less (2.3/5) than the overall mean (3.0/5).
Influence of Moisture on Cold Hardiness of Six Container-Grown Herbaceous Perennials
Authors: Kingsley-Richards S.L. , Perry L.P.
Published: August 2020

Overwintering container-grown plants is often necessary during production. Plants maintained in pots at growing medium moisture levels above (‘wet’) and below (‘dry’) 10% volumetric water content were exposed to −2, −5, −8, −11, and −14 C (28, 23, 18, 12, 7 F) in January, then returned to a greenhouse kept at 3 to 5 C (37 to 41 F). In June, plants were assessed using a visual rating scale (1 = dead, 3 to 5 = increasing quality) and shoot dry weight of new foliage growth. Quality rating and shoot dry weight of Coreopsis L. ‘Tequila Sunrise’ and Carex morrowii Boott. ‘Ice Dance’ were not affected by moisture level. Quality ratings were higher for Geranium × cantabrigiense L. ‘Cambridge’ ‘wet’ plants than for ‘dry’ plants and for Heuchera L. ‘Plum Pudding’ ‘dry’ plants than for ‘wet’ plants. Shoot dry weight was higher for ‘dry’ plants of Carex laxiculmis Schwein. ‘Hobb’ (Bunny Blue™) and Carex oshimensis L. ‘Evergold’ exposed to most temperatures. Of the cultivars studied, effects of moisture level on overwintering container-grown plant growth and quality are cultivar-specific and a universal effect could not be established.
Evaluation of Chitinase Activity in Tall Fescue Cultivars Inoculated with Rhizoctonia solani
Authors: Cutulle Matthew , Derr Jeffrey , McCall David , Nichols Adam , Horvath Brandon , Sanchez Tatiana
Published: August 2020

Tall fescue has great utility as a low maintenance turfgrass in the northern and transition zone regions of the United States. A factor limiting tall fescue utility is its susceptibility to the pathogen Rhizoctonia solani Kuhn, the causal agent of foliar brown patch. Chitinase activity has been positively correlated with resistance to R. solani in other plant species. A chitinase assay was developed for tall fescue. Three tall fescue cultivars with differing agronomic qualities and brown patch susceptibility as well as a resistant hybrid bluegrass cultivar were inoculated with R. solani in a greenhouse humidity chamber. Chitinase activity 48 hours after inoculation was negatively correlated with percent brown patch severity 10 days after inoculation. ‘Jaguar’ tall fescue was the most tolerant to R. solani and exhibited the highest chitinase activity before and after inoculation. No significant increase in chitinase activity was observed in the other tall fescue cultivars following R. solani inoculation. Identifying tall fescue cultivars expressing high amounts of chitinase activity could be important for developing brown patch-tolerant tall fescue cultivars.
Pinching, Daminozide and Night-interrupted Lighting Start Date Affect Growth and Flowering of Achillea × ‘Coronation Gold’
Authors: Li Mohan , Kessler J. Raymond , Keever Gary J. , Foshee Wheeler G.
Published: August 2020

A study was conducted to determine the effects of pinching and the plant growth retardant, daminozide (B-Nine), on plant size and flowering of ‘Coronation Gold’ yarrow (Achillea × ‘Coronation Gold’). Greenhouse-grown plants were not pinched or were pinched by removing the apical bud from propagation offsets 3, 5 or 7 weeks after potting. One week after pinching, plants were provided night-interrupted lighting (NIL). Five weeks after pinching, a single application of daminozide was applied at 5,000 ppm to half the pinched and non-pinched plants. Pinching decreased inflorescence stem length by 6.4% and increased the number of flowering and total offsets by 33.3 and 9.1%, respectively. Daminozide application decreased inflorescence stem length and the number of flowering offsets by 7.9 and 40%, respectively, but increased the time to first open inflorescence and the number of non-flowering offsets by 6 days and 28.6%, respectively. Pinching at 7 weeks after potting resulted in the highest number of flowering, non-flowering, and total offsets, the fewest days to flower, and an intermediate flower stem length. In a second experiment, the effects of beginning NIL at different times after pinching the offset from propagation on offset production and flowering were evaluated. All plants were uniformly pinched and NIL was started 0, 1, 2, 3, or 4 weeks after pinching. Starting NIL at 4 weeks after pinching resulted in the fewest days to flower, the highest flowering offset number that was similar to starting NIL at 3 weeks, and a flower stem length about equal to all other NIL treatments.
Structural Breaks and Future Growth of the Green Industry
Authors: Perez Maria , Palma Marco , Behe Bridget , Hall Charles
Published: August 2020

Every industry undergoes changes, but structural changes can abruptly and radically alter business for many firms in that industry. Identifying the substantial shifts in the green industry with regard to consumer spending can help the industry better understand its history. Using an econometric model of that same consumer spending data to look forward to the future can show firms what might lie ahead. We analyzed the personal consumption expenditures for two items measured by the U.S. Bureau of Economic Analysis to identify structural breaks in the green industry. We then conducted an econometric forecast using that same data to predict future consumer spending projections to the year 2020. To accomplish this, we analyzed household expenditures for Tools (including gardening tools and equipment) and Plants (including seeds, flowers, and plants) from 1959 to 2014. We identified one industry structural break using the Schwarz criteria for Tools in 2006 and another one for Plants in 2007 and (separately) identified four breaks using Bayesian Information criteria: one break for Tools in 2006 and three breaks in Plants in 1986, 2003, and 2008. The potential causes of these breaks are discussed (e.g. housing bubble, financial market stress). Lastly, we employed an econometric model to forecast spending and show that it will grow from $65.15 and $86.52 in 2015 to $71.17 and $96.97, for Tools and Plants respectively, in 2020.
Micronutrient Availability from Steel Slag Amendment in Pine Bark Substrates
Authors: Altland James E. , Locke James C. , Zellner Wendy L.
Published: August 2020

Steel slag is a byproduct of the steel industry that can be used as a liming agent, but also has a high mineral nutrient content. While micronutrients are present in steel slag, it is not known if the mineral form of the micronutrients would render them available for plant uptake. The objective of this research was to determine if steel slag could be used as the sole micronutrient source for container-grown nursery crops. Butterfly bush (Buddleja davidii ‘Pink Delight’) and rose (Rosa ‘Radrazz’) were grown in #3 (3 gal) containers in a base substrate composed of pine bark and peatmoss (80:20, by vol). The base substrate was amended with the following treatments: with a complete controlled release fertilizer (CRF) including micronutrients (C-control), a substrate amended with a different CRF containing only N, P, and K along with a granular micronutrient package (M-control), and three additional treatments amended with the CRF (N, P, and K only) and either 1.2, 2.4, or 4.8 kg·m−3 (2, 4, and 8 lb·yd−3) of steel slag. Plants were harvested at 2 and 4 months after potting (MAP). None of the plants displayed any sign of nutrient deficiency or toxicity throughout the experiment. However, plants grown in the substrate amended with the highest slag rate [4.8 kg·m−3 (8 lb·yd−3)] had lower shoot dry weight (SDW) than both control groups. Substrate pH increased with increasing slag rate, which may have affected micronutrient availability in those substrates. Among the micronutrients analyzed, only Copper (Cu) was consistently deficient in both the substrate and foliar tissue of slag-amended treatments. Steel slag either does not provide a sufficient quantity of Cu or the concomitant increase in pH with increasing rates of steel slag renders Cu unavailable for plant uptake. Steel slag should not be used as the sole source of micronutrients for shrubs grown in pine bark-based substrates.
Vegetative Stem Cutting Propagation of Idesia polycarpa
Authors: Wilson Barrett C. , Taylor Matthew D. , Zale Peter J.
Published: August 2020

Idesia polycarpa, Igiri tree, is a deciduous ornamental tree with 10 to 20 cm (4 to 8 in) long panicles of yellow-green flowers in spring and summer, maturing to ornamental orange-red berries in fall and winter. There are limited vegetative propagation protocols established for I. polycarpa. The objective of this study was to evaluate the effectiveness of different timing and auxin concentration combinations on rooting success of shoot tip cuttings. In 2009, there were nine collection dates of softwood cuttings during the summer and three indole-3-butyric acid (K-IBA) concentrations of 0, 5,000, and 10,000 mg·L−1 (PPM). Increasing the K-IBA rate to 10,000 mg·L−1 resulted in higher rooting percentages for most collection dates, though rooting percentage did not exceed 32% for any given treatment combination. The date cuttings were taken did not affect rooting percentage. Cuttings that did not receive K-IBA did not root. In 2010, the impact of cutting harvest date (softwood in June and semi-hardwood in September) and the effect of K-IBA rate (0, 10,000, and 20,000 mg·L−1) on rooting was determined. There was no statistical difference between the two higher concentrations, but both improved rooting versus the nontreated control, which did not root. Softwood cuttings showed a higher rooting percentage and greater root length compared to semi-hardwood cuttings.
Landscape Establishment for Baldcypress, Red Maple, and Chaste tree is Delayed for Trees Transplanted from Larger Containers1
Authors: Chance Lauren M. Garcia , Arnold Michael A. , Lombardini Leonardo , Watson W. Todd , Carver Sean T. , King Andrew R.
Published: August 2020

With container-grown trees offered to the public in an increasing array of sizes, it is important to determine the effects of different sizes of container stock on transplant establishment. Clonal replicates of Vitex agnus-castus, Acer rubrum var. drummondii, and Taxodium distichum grown under common nursery conditions in five container sizes, 3.5, 11.7, 23.3, 97.8, or 175.0 L (#1, #3, #7, #25, or #45, respectively), were transplanted to a sandy clay loam field. Physiological stress was measured using xylem water potential and photosynthetic gas exchange rates. Height, trunk diameter, and canopy spread were monitored post-transplant for three growing seasons and root growth was sampled for the first two growing seasons. Trees of all three species from smaller-sized containers, 23.3 L (#7) or less, exhibited reduced transplant shock, decreased establishment time and increased growth rates in comparison to larger-sized containers, apart from increased mortality in 3.5 L (#1) A. rubrum and slower growth in 3.5 L (#1) T. distichum compared to those transplanted from 11.7 L (#3) or 23.3 L (#7) containers Reduced stress levels and increased growth rates corresponded in timing with greater change in root extension of smaller container-grown trees. At the end of three growing seasons, no statistical differences in height or trunk diameter were present for V. agnus-castus container sizes. With a modest wait, consumers may find that smaller container-grown trees will overcome transplant stress more quickly and exhibit growth rates that surpass those of larger container-grown trees.

Index words: Acer rubrum, Taxodium distichum, Vitex agnus-castus, container-grown trees, transplant shock, transplant establishment, photosynthesis, transpiration, water stress.

Species used in this study: Chaste tree (Vitex agnus-castus L. [an unnamed white flowering clone]); red maple (Acer rubrum L. var. dummondii [Hook. & Arn. ex Nutt.] Sarg. ‘Maroon'); bald cypress (Taxodium distichum (L.) Rich. [test clone TX8DD38]).
Evaluating Impacts of Brown Marmorated Stink Bug on Non-fruiting Nursery Crops1
Authors: Skillman Victoria P. , Lee Jana C.
Published: August 2020

Halyomorpha halys (Stål), the brown marmorated stink bug or BMSB, has become a major pest and nuisance since it arrived in the U.S. in 1996. This insect can feed on approximately 200 different plant species, many of which are important ornamental crops. BMSB's preference for fruits and the damage they cause is known, but it is not known how their presence on non-fruiting woody ornamentals can impact vegetative growth. The first study confined adult BMSB to branches of established stock block trees of five plant species for one month. Four measurements were taken to assess plant growth: branch length, leaf area, number of leaves, and dry weight. The second study confined adult BMSB on seedlings of eight plant species for one or two months. In this study, the same four measurements were taken as well as the change in trunk diameter. Overall, there were no significant differences in plant growth and only some marginal differences between branches or seedlings caged with BMSB versus no BMSB (control) after one or two months. Adults laid eggs on all plants species in both trials, and nymphs were observed to develop to the 2nd instar stage in the seedling trial on all the plant species except for maple. Confinement of BMSB on branches of well-established nursery plants or on newly planted seedlings had little or no impact on growth over a two month exposure.

Index words: Halyomorpha halys, Hemiptera, ornamentals, seedling, vegetative growth.

Species used in this study: Brown marmorated stink bug (Halyomorpha halys Stål); Dolgo crabapple (Malus sp.); Yoshino cherry (Prunus yedoensis Matsum.); Japanese elm (Ulmus davidiana Planch.); Siberian elm (Ulmus pumila L.); Ginkgo (Ginkgo biloba L.); Washington hawthorn (Crataegus phaenopyrum (L.f.) Medik); lsquo;Ivory Silk' lilac (Syringa reticulata Blume); ‘Green Mountain' silver linden (Tilia tomentosa Moench); ‘Crimson Sunset' maple (Acer truncatum Bunge); ‘Franksred' maple (Acer rubrum L.)
Effects of a Nonionic Surfactant on Growth, Photosynthesis, and Transpiration of New Guinea Impatiens in the Greenhouse1
Authors: Sibley Jeff L. , Yang Xiaomei , Lu Wenliang , Eakes D. Joseph , Gilliam Charles H. , Foshee Wheeler G. , Pickens Jeremy M. , Zinner Bertram
Published: August 2020

Production of quality greenhouse and nursery crops is dependent on high quality and quantities of water. At present, in some regions, insufficient water supply is a growing concern. This study was conducted to evaluate growth of New Guinea impatiens (Impatiens hawkerii 'Celebrate Salmon'), when watered with a polyoxyethylenesorbitan monolaurate (C58H114O26) solution commercially known as Tween 20, at differing irrigation levels compared with a conventional water regimen without the surfactant, and also to determine how Tween 20 would affect photosynthesis and transpiration. The treatment design was a 3 by 6 complete factorial design plus a control. The two factors were irrigation and Tween 20. Irrigation levels of 20%, 40%, or 60% of the full crop evapotranspiration (ET) requirements were used in combination with Tween 20 concentrations of either 0, 25, 50, 75, 100, or 125 mg·L−1 (0, 0.003338, 0.00668, 0.0100145, 0.01335, or 0.01669 oz per gallon). The control group was watered with tap water to container capacity with about 30% leachate. Evapotranspiration was determined as the difference of the applied water amount minus the leachate of the control. Plants irrigated with Tween 20 from 25 to 125 mg·L−1 (0.003338 to 0.01669 oz per gallon) at the 40% or 60% irrigation level had the same height and growth index as plants in the control after three months of growth. Plant fresh and dry weights were not different between the control and the treatments of Tween 20 from 50 to 125 mg·L−1 (0.00668 to 0.01669 oz per gallon) at the 60% irrigation level or the treatment of Tween 20 at 100 mg·L−1 (0.01335 oz per gallon) at the 40% irrigation level. Tween 20 had no effect on net photosynthetic rate. Tween 20 decreased the amount of transpired water of New Guinea impatiens 'Celebrate Salmon'. When the Tween 20 concentration increased from 0 to 100 mg·L−1 (0 to 0.01335 oz per gallon) at the 60% irrigation level, the transpiration rate and stomatal conductance decreased markedly by 43% and 47%, respectively, and water use efficiency was increased by 47%. Results from this study suggest that Tween 20 is able to increase plant water use efficiency through regulation of stomatal conductance or transpiration under deficit irrigation.

Index words: irrigation management, chemigation, source-sink physiology, deficit irrigation, wetting agent, Tween 20, adjuvant.

Species used in this study: New Guinea Impatiens (Impatiens hawkerii W. Bull. 'Celebrate Salmon').

Chemicals used in this study: Tween 20 (polyoxyethylenesorbitan monolaurate). (aka: polysorbate 20, polyoxyethylene (20) sorbitan monolaurate)