bluuebunny/crossref_metadata_2025_split huggingface dataset:
Evaluation of Selected Preemergence Herbicides in Field-Grown Landscape Crops in Kentucky
Authors: Setyowati N. , Weston L. A. , McNiel R. E. 
Published: August 2020

Abstract
Research was conducted during 1990 and 1991 at the Horticultural Research Farm in Lexington, Kentucky, to evaluate the efficacy of herbicides available for use on woody landscape plants (simazine and oryzalin), newly labelled herbicides (isoxaben, isoxaben plus oryzalin, metolachlor and metolachlor plus simazine) and those not widely labelled for the nursery industry (oxyfluorfen and dithiopyr). Herbicide phytotoxicity was also evaluated in 10 species of woody nursery crops. Results 6 WAT (weeks after treatment) indicated that the standard of simazine at 1.1 kg ai/ha (1.0 lb/A) plus oryzalin at 3.3 kg ai/ha (3.0 lb/A) provided adequate control of most common broadleaf weeds (98%) and annual grasses (98%) but not yellow nutsedge (31%). Isoxaben plus oryzalin at 4.2 kg ai/ha (4.0 lb/A) (DF formulation) and isoxaben plus trifluralin at 4.2 kg ai/ha (4.0 lb/A) (granular formulation) gave excellent full-season control of nearly all broadleaf and grass weeds with the exception of galinsoga and field bindweed. In addition, yellow nutsedge control was acceptable, ranging from 63 to 96% in these treatments. Isoxaben alone also provided excellent broadleaf control (93%) 6 WAT in 1990 but poorer (&lt;70%) control of giant foxtail, galinsoga and velvetleaf by 12 WAT. Dithiopyr (granular formulation) provided excellent full-season residual control of broadleaf weeds, nutsedge and grasses at the highest rate of 2.2 kg ai/ha (2.0 lb/A). Oxyfluorfen at the higher rate (2.2 kg ai/ha) (2.0 lb/A) also controlled all species except yellow nutsedge. Poor broadleaf control was obtained 12 WAT with 3.3 kg ai/ha (3.0 lb/A) metolachlor or metolachlor plus simazine at rates up to 4.4 kg ai/ha (4.0 lb/A) in both 1990 and 1991. Pronamide at 2.2 kg ai/ha (2.0 lb/A) did not provide adequate control of either broadleaf or grasses at 6 or 12 WAT. No visible phytotoxicity to woody ornamentals was observed in either season up to 8 weeks after application. However, growth reductions were noted in both common lilac and red oak stem or trunk diameter following treatment with isoxaben at 1.1 kg ai/ha (1.0 lb/A).
Evaluation of New Systemic Insecticides for Elm Insect Pest Control
Authors: Sclar D. Casey , Cranshaw Whitney S. 
Published: August 2020

Abstract
Use of systemic insecticides that can be injected either into the root system or trunk of woody plants provides several potential advantages, notably in control of drift during application. Recently, new classes of insecticides with systemic activity have been developed, which may supplant the organophosphate and carbamate systemic insecticides that have previously been available. To evaluate their potential to control insects affecting shade trees, studies were conducted using imidacloprid and abamectin on elm. Soil injections of imidacloprid appeared particularly effective, controlling all three of the target pest species in this study (elm leaf beetle, European elm scale, elm leaf aphid). Both imidacloprid and abamectin also were effective against at least some elm insects when injected into trunks. Persistence of irnidacloprid was unusually long, providing second season control of all elm insect pests, although root uptake following soil injections was slow.
Gas Exchange Rates for Selected Red Maple Cultivars Grown in Alabama
Authors: Sibley Jeff L. , Eakes D. Joseph , Gilliam Charles H. , Keever Gary J. , Dozier William A. 
Published: August 2020

Abstract
The objective of this study was to develop a rapid screening technique to characterize selected red maple (Acer rubrum L.) cultivars based on their gas exchange capacities. Evaluations were conducted in Alabama under ambient conditions on an established, irrigated field trial. In preliminary evaluations 9 red maple cultivars (‘Autumn Flame’, ‘Fairview Flam’, ‘Franksred’, ‘Karpick’, ‘Northwood’, ‘October Glory’, ‘Redskin’, ‘Schlesingeri’, and ‘Tilford’) and 3 Freeman maple (Acer x freemanii E. Murray) selections (‘Autumn Blaze’, ‘Morgan’, and ‘Scarsen’) were observed for differences in net photosynthesis (Pn), transpiration (E), and stomatal conductance (Cs). Based on these results, 4 cultivars of A. rubrum were selected and evaluated intensively over 2 years. Throughout the study, growth rates for the 4 selections failed to correspond with gas exchange observations.
Host-Parasite Relationships of Susceptible and Resistant Elm Callus Cultures Challenged with Ophiostoma ulmi (Buisman) Nannf.
Authors: Krause C. R. , Ichida J. M. , Schreiber L. R. , Domir S. 
Published: August 2020

Abstract
Ultrastructural effects of Ophiostoma ulmi (Buisman) Nannf..(= Ceratocystis ulmi Buisman C. Moreau) on susceptible American elm (Ulmus americana L.) callus tissue consisted of extensive vacuolation, accumulation of cytolytic substances, and plasmolysis when viewed with electron and light microscopy. Infected resistant American elm callus tissue revealed slight cell wall damage with some phenolic-like deposits but adjacent cells, membranes, mitochondria and nuclei were intact. Fungal hyphae that adhered to callus grown from susceptible American elm plants were regularly observed. Sparse hyphal growth was not suspended above resistant American elm callus cells. Callus from nonhost and resistant elms showed reduced hyphal growth between host cells compared to susceptible elm with increased accumulation of extracellular, phenolic-like deposits than in callus of American elm. The fungal structures on resistant tissue showed evidence of irregular growth and morphology. The latter suggest a phytoalexin-like response by the resistant American elm callus tissue.
Vegetation Management Effects Growth of Leyland Cypress Grown for Christmas Trees
Authors: NeSmith D. Scott , Lindstrom Orville M. 
Published: August 2020

Abstract
Leyland Cypress trees x Cupressocyparis LeyLandii (A.B. Jacks. and Dallim.) Dallim. and A.B. Jacks. ‘Haggerston Grey’ were planted in the late winter of 1993 in a tall fescue (Festuca arundinacea Schreb.) sod. Vegetation-free circles of 0 (control), 0.6, 0.9, and 1.5 m (0, 2, 3 and 5 ft) diameters were maintained from 1993 to 1994 by a combination of commercially recommended herbicides and hand-weeding. The treatments resulted in vegetation-free areas of 0, 0.3, 0.6, and 1.8 m2 (0, 3, 7, and 19 ft2). Trees were mea sured over a 2 year period to determine the influence of vegetation-free area on growth. There were no differences in trunk cross sectional area or tree volume (calculated from height and width measurements) during 1993. By the spring of 1994, both trunk cross sectional area and tree volume increased with size of vegetation-free area. The influence of vegetation-free area on tree growth was even more pronounced by the fall of 1994. These results indicate vegetation control is important in establishing Leyland Cypress for Christmas trees. The optimum vegetation-free area appears to be between 0.6 m2 and 1.8 m2 (7 and 19 ft2) during the second year of growth.
Weed Control With Herbicide-Coated or -Blended Fertilizer in ‘August Beauty’ Gardenia
Authors: Crossan C.K. , Gilliam C.H. , Eakes D.J. , Keever G.J. , Wehtje G.R. , Dozier W.A. 
Published: August 2020

Abstract
Prostrate spurge (Euphorbia maculata L.) control and injury to container-grown ‘August Beauty’ gardenia (Gardenia jasminoides Ellis) were evaluated using Ronstar 50WP (oxadiazon) or Pennant 7.8E (metolachlor)-coated or Ronstar 2G (oxadiazon) or Pennant 5G (metolachlor)-blended Nursery Special 12N–2.6P–5.0K (12–6–6) fertilizer. Herbicides were applied at 4 rates, 2.3, 4.5, 9.0, and 18.0 kg ai/ha (2, 4, 8, and 16 lb ai/A) and compared to broadcast and spray applied pre-emergence herbicide applications at 4.5 kg ai/ha (4 lb ai/A). Ronstar (oxadiazon)-coated or -blended Nursery Special at all rates, except 2.3 kg ai/ha (2 lb ai/A) provided similar weed control to the broadcast or spray applied controls. Pennant (metolachlor)-coated or -blended fertilizer controlled spurge only at 18.0 kg ai/ha (16 lb ai/A). Weed control was similar when comparing herbicide formulation (coated vs. blended). Gardenia growth was similar among treatments and no injury symptoms were observed with any treatment.
Landscape Maintenance Firms: I. Business Features and Factors Influencing Industry Performance
Authors: Garber M.P. , Bondari K. 
Published: August 2020

Abstract
Seventy-two completed questionnaires sent to landscape maintenance firms in Georgia were received for a response rate of about 38%. Approximately two-thirds of the landscape maintenance firms were located in the metro Atlanta area and about 98% of their projects were in Georgia. Firms surveyed were involved primarily (approximately 95% of their projects) in outdoor maintenance activities, however, 50% of the large firms were involved in some level of indoor plant maintenance. Three size classes of firms were established based on their 1993 wholesale value of plant material purchased, small (&lt;$25K), medium ($25K-$100K), and large (&gt;$100K). The large firms accounted for 26% of the respondents, 72% of the gross revenue, and 79% of the plant materials purchased. Plant material purchased from growers (52.5%), rewholesalers (35.0%), brokers (8.5%), and garden centers (3.9%) accounted for 99.9% of plants purchased by landscape maintenance firms. Industry trends most frequently identified by respondents to have a positive impact on the industry over the next 5 years were: (1) an improving economy (38.7%), (2) consumer emphasis on plant quality (18.1%), and (3) alternative debris disposal such as composting and recycling (12.6%). The 3 trends with the greatest potential for negative impact on the industry were identified as: (1) unprofessional, new firms that submit unrealistic low bids (28.4%), (2) mandatory employee benefits and government regulations (22.7%), and (3) public concern regarding pesticide safety (17.0%).
Interior Plants May Improve Worker Productivity and Reduce Stress in a Windowless Environment
Authors: Lohr Virginia I. , Pearson-Mims Caroline H. , Goodwin Georgia K. 
Published: August 2020

Abstract
This study documents some of the benefits of adding plants to a windowless work place—a college computer lab. Participants' blood pressure and emotions were monitored while completing a simple, timed computer task in the presence or absence of plants. When plants were added to this interior space, the participants were more productive (12% quicker reaction time on the computer task) and less stressed (systolic blood pressure readings lowered by one to four units). Immediately after completing the task, participants in the room with plants present reported feeling more attentive (an increase of 0.5 on a self-reported scale from one to five) than people in the room with no plants.
Compost and Rubber Tire Chips as Peat Substitutes in Nursery Container Media: Effects on Chemical and Physical Media Properties
Authors: Jarvis Beth R. , Calkins James B. , Swanson Bert T. 
Published: August 2020

Abstract
Physocarpus opulifolius ‘Dart's Gold’, Forsythia x ‘Meadowlark’, Spiraea x billiardii, Juniperus chinensis ‘Seagreen’, J. sabina ‘Mini Arcade’, J. horizontalis ‘Hughes’, and Lamiastrum galeobdolon were grown in container media amended with three yard waste (YW) composts, one municipal solid waste (MSW) compost and shredded rubber tire chips. Each of the five amendments was used to replace 50% or 100% of the sphagnum peat in a standard container medium resulting in eleven media treatments. Effects of peat replacement with compost or tire chips were compared relative to chemical and physical media characteristics. Amendments evaluated had limited long term nutritional value. Initial pH was increased when peat was replaced with compost or rubber tire chips; the increase in pH was proportional to the amount of peat replaced (50 or 100%). Over time, pH of all media equilibrated with irrigation water pH. Soluble salts were reduced for media amended with rubber tire chips while peat replacement with compost had variable effects on soluble salt levels based on compost source. Media amended with compost exhibited increased bulk density and decreased porosity, water infiltration capacity and water holding capacity compared to the standard, peat-based control medium. Peat replacement with rubber tire chips increased bulk density and porosity and decreased water holding capacity compared to the standard control medium. Water infiltration capacity was greatly increased and water holding capacity decreased when peat was replaced 100% with rubber tire chips.
Rooting of ‘Brown Velvet’ Southern Magnolia Stem Cuttings as Influenced by Medium and Auxin Treatment
Authors: McCracken T. Patrick , Catanzaro Christopher J. , Bilderback Ted E. 
Published: August 2020

Abstract
Terminal stem cuttings of ‘Brown Velvet’ Southern magnolia (Magnolia grandiflora L. ‘Brown Velvet’) were treated with 0.3% indole-3-butyric acid (IBA) in talc, or 0.5% naphthaleneacetic acid (NAA) quick dip + 0.3% IBA in talc, or 0.5% NAA + 1.0% IB A quick dip. Rooting media included pine bark, perlite, or combinations of bark and perlite at the following ratios: 3:1, 1:1, 1:3 (by vol). Cuttings were rooted in a greenhouse mist bed supplied with bottom heat. Rooting percentage was unaffected by media with the exception of a decreased response in perlite. Root length and secondary root formation was greater with pine bark than with perlite, while the bark/perlite blends provided an intermediate response. Increased auxin concentrations produced more primary roots but reduced formation of secondary roots. However, rooting percentage was not affected by auxin treatment. Results suggest that medium selection is more important than auxin source or delivery method in the rooting of ‘Brown Velvet’ Southern magnolia.
Factors Influencing Seed Germination of Lupinus perennis
Authors: Mackay Wayne A. , Davis Tim D. , Sankhla Daksha , Riemenschneider Don E. 
Published: August 2020

Abstract
Seeds of Lupinus perennis Wats. (perennial lupine) were subjected to a variety of scarification and temperature treatments. Without scarification, &lt;15% germination was observed within 1 week. Germination increased quadratically as the duration of acid scarification time increased. After 15 min scarification, nearly 90% of the seeds germinated and nearly 100 percent germination was obtained after 45 min scarification. Nicking the seed coats with a razor blade resulted in 100% germination. In contrast, soaking seeds in 22C (72F) water for 24 hr failed to enhance germination. Total germination of scarified seeds was &gt;80% between 21 and 29C (70 and 85F) within 54 hr. The most rapid germination occurred within 24 to 29C (75 to 85F). At 32C (90F), total germination was reduced to approximately 60%. At temperatures ≥ 35C (95F), total germination was reduced to less than 4%. Germination occurred equally well in the light or dark. Our data indicate that seeds of L. perennis must be scarified to germinate and the most rapid germination occurs between 24–29C (75–85F).
Freezing Date and Duration Effects on Regrowth of Three Species of Container—grown Herbaceous Perennials
Authors: Perry Leonard P. , Herrick Todd 
Published: August 2020

Abstract
Three species of herbaceous perennials were transplanted from 400 cell-size plugs to 400-ml containers and grown in a glasshouse at 25C day/20C night (78/68F) ± 2C (4F) until October 10. At that time glasshouses were programmed for ambient outdoor temperatures, but maintained above 3C (38F) ± 2C at night. Plants were exposed in controlled programmable freezers to four freezing temperatures [−5,−5,−11 and −14C (23, 18,12,7F)] on November 15,1995, and January 1, 1996. Plants were allowed to remain at each temperature for either 30 or 120 minutes. Plants were then returned to the glasshouse, and rated for survival and salability following 6 weeks regrowth at 15C (59F). The rating scale was subjective and ranged from 1 to 5 (1 = worst, 5 = best, 3 and above considered salable). Regrowth means of all three species declined as treatment temperatures decreased. Although freezing date had a significant influence on regrowth quality of Aquilegia and Dianthus, only freezing duration influenced Dianthus regrowth. Neither factor significantly influenced regrowth quality of Lavandula. Treatment temperature and its interaction with freezing date or duration was statistically significant for all three species. All plants remained marketable following exposure to −11C (12F).
Effects of Plant Growth Regulators on Sturdiness of Jack Pine Seedlings
Authors: Schnurr Jeffrey P. , Cheng Zong-Ming , Boe Arthur A. 
Published: August 2020

Abstract
Seven growth regulators (ancymidol, 6-benzylaminopurine, ethephon, flurprimidol, mefluidide, paclobutrazol, and uniconizole) at various concentrations were studied for their effects on sturdiness of greenhouse grown seedlings of jack pine (Pinus banksiana Lamb.), measured by a single parameter, growth modification index. All growth regulators at certain concentrations were effective in reducing plant height but none increased stem caliper. Several growth regulators increased shoot-to-root dry weight ratio. Benzylaminopurine greatly modified growth characteristics and resulted in deformed seedlings. Uniconizole was most promising for producing sturdier seedlings of jack pine.
Biosolids Improve Rooting of Bougainvillea (Bougainvillea glabra) Cuttings
Authors: Atzmon Nir , Wiesman Zeev , Fine Pinchas 
Published: August 2020

Abstract
Cuttings of Bougainvillea glabra were placed in 80-ml (4.9 in3) containers containing rooting medium mixed with various concentrations of biosolids (1, 2.5, 5 and 7.5%) from two sources (Herzliyya and Haifa). Two biosolids-free control media were used (with or without addition of mini-Osmocote fertilizer). Half of the cuttings were treated with IBA. The rooting percentage was improved by adding biosolids to rooting media. Treating cuttings with IBA without biosolids was inferior to some of the biosolid treatments. Root development was significantly stimulated by the biosolids compared with a slow-release fertilizer treatment. However, the effect of biosolids on shoot development was slightly improved. Generally, high concentrations of Herzliyya biosolids showed the best results in rooting and growth, whereas Haifa biosolids were best at lowest concentrations.
Effects of Above-Ground Pot-in-Pot (PIP) Placement and Humic Acid Extract on Growth of Crape Myrtle
Authors: Schluckebier J.G. , Martin C.A. 
Published: August 2020

Abstract
Rooted cuttings of crape myrtle (Lagerstroemia indica L. × L. fauriei Koehne ‘Muskogee’) were potted into 3.8 liter (1 gal) black polyethylene containers and subjected for two months to one of three above-ground shielding treatments; containers placed pot-in-pot (PIP) for two months, containers exposed to direct sunlight for two months, or containers placed PIP for one month and then exposed to sunlight for one month (PIP/exposed). Mean daily maximum temperatures in rooting substrate of containers exposed to sunlight were as much as 16C (29F) higher than PIP containers. Plants in containers exposed to sunlight for two months had less total root and shoot length and higher concentrations of leaf nitrogen compared with the other two treatments. Plants were next transplanted into 27-liter (7-gal) polybags filled with a landscape substrate and fertigated with a humic acid extract at 0, 50, 150, or 300 μL/L for two additional months. The change in shoot and root length of plants previously placed PIP for two months responded in quadratic fashion to increased humic acid extract concentration levels; the most response occurred at about 50 μL/L while the highest concentrations inhibited post-transplant growth. Growth inhibition caused by heat stress as a result of exposure of container walls to insolation was still evident two months after transplanting.
Production of Six Woody Landscape Plants in Copper-coated and Styrene-lined Containers
Authors: Brass Thomas J. , Keever Gary J. , Gilliam Charles H. , Eakes D. Joseph , Hesselein Charles P. 
Published: August 2020

Abstract
Growth of Rhododendron L. ‘Hershey's Red’ (azalea), Magnolia grandiflora L. (magnolia), Ilex × meserveae S.Y. Hu. ‘Blue Princess’ (holly), Pittosporum tobira (Thunb.) Ait. (pittosporum), Gardenia jasminoides Ellis ‘August Beauty’ (gardenia), and Nerium oleander L. (oleander) were evaluated for 8 months in 3.8 liter (#1) containers treated with (+) or without (−) copper hydroxide (Cu) and with (+) or without (−) a styrene lining. Plants were then repotted into 10.3 liter (#3) untreated containers to determine treatment effects on root regeneration and shoot growth. In addition, azalea, gardenia, and holly were planted in the ground to evaluate root regeneration and shoot growth during landscape establishment. All species tested had less root growth at the substrate-container interface at the end of the first growing season when grown in Cu-treated containers. Other growth parameters measured (height, trunk diameter, growth index) varied among species in response to Cu treatment. One growing season (11 months) after repotting into 10.3 liter (#3) containers, all species had less surface root coverage when the original 3.8 liter (#1) container was Cu-treated. Dry weights of newly generated roots outside the original rootball of repotted or transplanted plants were not affected by Cu or styrene treatment, except for a lower root dry weight of holly when previously grown in +Cu containers. After repotting into larger containers, shoot growth in response to Cu was species-dependent. Transplanted azaleas had a lower growth index after transplanting from +Cu containers than from −Cu containers. Growth index of gardenia was increased after repotting into 10.3 liter (#3) containers from 3.8 liter (#1), styrene-lined containers; surface root coverage 5 months after repotting also was increased when plants were previously grown in styrene-lined containers. Oleander, holly, and magnolia previously grown for 8 months in 3.8 liter (#1), styrene-lined containers without Cu all had more surface root coverage after being grown for 11 months in 10.3 liter (#3) containers compared to plants grown in unlined containers.
Nitrogen Nutrition of Containerized Cupressus arizonica var. glabra ‘Carolina Sapphire’
Authors: Stubbs Hunter L. , Warren Stuart L. , Blazich Frank A. , Ranney Thomas G. 
Published: August 2020

Abstract
Rooted stem cuttings of ‘Carolina Sapphire’ smooth Arizona cypress [Cupressus arizonica var. glabra (Sudw.) Little ‘Carolina Sapphire’] grown in calcined clay in 3.8 liter (#1) containers were fertilized daily for 16 weeks with a complete nutrient solution containing 0, 20, 40, 80 or 160 mg N/liter supplied as ammonium nitrate. Plant heights and stem diameters were unaffected by N rate suggesting that a daily nutrient application of 20 mg N/liter was adequate for maximizing growth. Nitrogen fertilization increased heights and stem diameters by 71% and 56%, respectively, compared to the nontreated controls (0 mg N/liter). Even though shoot growth was unaffected by increasing N levels, foliage N concentration was positively correlated (r = 0.75, P &lt; 0.0001) to N levels. As N concentration increased, total root area and total root length increased quadratically. Nitrogen fertilization increased root area and root length 119% and 108%, respectively, compared to the nontreated controls. Phosphorus concentration of shoots increased quadratically with increasing N levels. Nitrogen rate failed to affect K concentration of shoots. Shoot Ca and Mg concentrations decreased with increasing N levels.