bluuebunny/crossref_metadata_2025_split huggingface dataset:
Seed Germination of Three Provenances of Rhododendron catawbiense: Influence of Light and Temperature
Authors: Rowe D. Bradley , Blazich Frank A. , Warren Stuart L. , Ranney Thomas G. 
Published: August 2020

Abstract
Seeds of three provenances of Rhododendron catawbiense Michx. (Catawba rhododendron) were collected during Fall 1992 from the following localities in the southeastern United States: Cherokee Co., GA [34°20′N, 84°23′W, elev. = 320 m (1050 ft)], Johnston Co., NC [35°45′N, 78°12′W, elev. = 67 m (220 ft)], and Yancey Co., NC [35°45′N, 82°16′W, elev. = 1954 m (6410 ft)]. Following drying for 1 month and storage at 4°C (39°F), seeds were removed from storage in January 1993 and germinated at 25°C (77°F) or an 8/16 hr thermoperiod of 25°/15°C (77°/59°F) with daily photoperiods of 0, ½, 1, 2, 4, 8, 12, or 24 hr. Regardless of temperature and provenance, seeds required light for germination. Negligible germination for all provenances in total darkness was overcome by daily photoperiods as short as ½ hr. All provenances commenced germination earlier at 25°C (77°F) than at 25°/15°C (77°/59°F). Mean germination at day 24 for both temperature treatments and for all photoperiods with the exception of total darkness was 98%, 90%, and 80% for the Yancey, Johnston, and Cherokee Co. provenances respectively. Light and temperature requirements for seed germination of all provenances were similar, although seeds of the higher elevation, Yancey Co. provenance exhibited greater vigor; they germinated at a faster rate with greater cumulative germination.
Ornamental Grasses For Minnesota
Authors: Meyer M. Hockenberry , White D. B. , Pellett H. 
Published: August 2020

Abstract
One hundred and sixty-five (165) species and cultivars of ornamental grasses and grass-like plants were investigated to determine winter survival in USDA Zone 4a from 1987 to 1993 at the Minnesota Landscape Arboretum, Chanhassen, MN. Eighty-five (85) entries survived and performed well all six years and are considered hardy under the conditions of the experiment. Additionally, 35 entries survived four or five of the six years and are considered marginally hardy. The remaining 45 entries survived no more than two winters and are not hardy in zone 4a. Hardiness varied within species of Miscanthus sinensis Anderss. and Pennisetum alopecuroides (L.) Spreng..Saccharum ravennae (L.) Murray, synonym (Erianthus ravennae); Imperata cylindrica L. ‘Red Baron’; and Chasmanthium latifolium (Mic.)Yat. were not considered hardy. Some popular genera such as Calamagrostis, Deschampsia, Molinia, and Spodiopogon were reliably hardy throughout the years of the investigation.
Early Lifting and Transplanting of Flowering Dogwood Seedlings Increases Survival in the Southern United States
Authors: Ruter J.M. , Garber M.P. , Moorhead D.J. 
Published: August 2020

Abstract
Effects of lift date and photoperiod on budbreak and survival of 1-0 flowering dogwood (Comus florida L.) seedlings were studied under greenhouse conditions while survival was evaluated on plants transplanted in field plots. Seedlings were lifted from field beds on October 3, 1990; October 31, 1990; November 28, 1990; December 18, 1990; and February 5, 1991 (0, 63, 192, 357, and 851 chill hours, respectively (&lt;7°C, 45°F)) and were placed in photoperiod chambers (10, 12, and 14 hr) constructed in a greenhouse or planted in the field under natural conditions. Increasing photoperiod under greenhouse conditions decreased the number of days to budbreak across lift dates. Photoperiod had no effect of survival. Survival of greenhouse plants was greater than 85% for all but the February lift date (72%). Survival of plants in the field decreased to 50% for the December lift date compared to &gt;90% for both October lift dates. Mean survival across lift dates for the greenhouse and field plants were 88% and 77%, respectively. No differences in shoot growth or root regeneration were seen between treatments for greenhouse-grown plants. Results of these studies suggest that bareroot seedlings of flowering dogwood should be lifted and planted in the fall for optimal survival in the warmer areas of the southern United States.
Mid-Season Reapplication of Controlled Release Fertilizers Affect ‘Helleri’ Holly Growth and N Content of Substrate Solution and Effluent
Authors: Shiflett Melinda C. , Niemiera Alex X. , Leda Carol E. 
Published: August 2020

Abstract
The objective of this study was to determine how a mid-season CRF (controlled release fertilizer) reapplication to container-grown Ilex crenata ‘Helleri’ Thunb. affected growth, substrate solution N content, and the amount on N leached compared to a single early season CRF application (control). ‘Helleri’ holly liners were initially fertilized (March 7) with an 8 to 9 month CRF, Osmocote 18N-2.6P-9.9K (18-6-12), or a 12 to 14 month CRF, Osmocote 17N-3.1P-9.9K (17-7-12). A subset of plants received a CRF reapplication (half rate) of the respective Osmocote formulation on July 19, August 2, or August 16. In addition, 12 plants received a water soluble fertilizer solution (WSF) with each irrigation starting on July 19. All effluent was collected and analyzed for N. Substrate solution N and electrical conductivity (EC) levels (via the pour-through method) and foliar N concentrations were determined every two weeks. Throughout the experiment, plants were irrigated with an irrigation amount that resulted in an ≈ 0.25 leaching fraction (LF). Plant width was determined on November 1. Plant width values were higher for the first and second reapplication and WSF treatments for both formulations than the control. However, in terms of commercial size grades, plants of all treatments were in the same grade. Thus, there was no economic advantage to reapplying CRF. We concluded that CRF reapplication was not necessary when substrate solution N and foliar N values were ≥ 20 mg N/liter and ≥ 2.3%, respectively. Irrigating at a LF of 0.2, the mid-season CRF application increased the amount of N lost from containers by 42% compared to a single, early season CRF application.
Nitrogen Nutrition of Containerized Cryptomeria japonica ‘Elegans Aurea’
Authors: Jull Laura G. , Warren Stuart L. , Blazich Frank A. 
Published: August 2020

Abstract
Containerized, rooted stem cuttings of ‘Elegans Aurea’ Japanese cedar [Cryptomeria japonica (L.f.) D. Don ‘Elegans Aurea’] grown in calcined clay, were fertilized three times weekly for 14 weeks with a complete nutrient solution containing 0, 25, 50, 100, or 200 mg N/liter supplied as ammonium nitrate. Top and root dry weights were not affected by N rate suggesting that 25 mg N/liter was adequate for maximizing growth. Nitrogen fertilization increased top and root dry weights by 149% and 20%, respectively, compared to the nontreated controls (0 mg N/liter). As N concentrations increased, root area and total root length decreased linearly. Nitrogen fertilization decreased root:top ratio by 50% compared to the nontreated controls. However, the root:top ratio was not affected by N rate. Percent top N concentration was increased by N compared to the nontreated control. Percent top K, Ca, and Mg decreased linearly with increasing N rates. There was a quadratic response in percent top P with a maximum at 50 mg N/liter.
Cold Hardiness of Landscape Pear Taxa
Authors: McNamara Steve , Pellett Harold 
Published: August 2020

Abstract
The cold hardiness of ten landscape pear cultivars and two pear species was evaluated in container- and field-grown plants during the dormant periods of 1991 through 1994. Timing and extent of acclimation by containerized plants overwintered in a temperature-moderated greenhouse was similar to that of plants growing in the field, indicating that containerized stock can be used for determining the hardiness of taxa lacking sufficient hardiness to survive outdoors in USDA Zone 4a. Among P. calleryana cultivars, ‘Autumn Blaze’ exhibited the best overall cold tolerance and greatest mid-winter hardiness [−34°C (−29°F)]. ‘Bradford’ was consistently the least hardy P. calleryana cultivar. All P. calleryana cultivars acclimated too slowly in the fall and or lacked sufficient mid-winter to survive in USDA Hardiness Zone 4a. Both P. salicifolia ‘Silver Frost’ and P. fauriei were hardier than the P. Calleryana cultivars on most sampling dates. P. ussuriensis was the hardiest taxon on all sampling dates and withstood −42°C (−44°F) by mid-December 1992. In field trials, only ‘Silver Frost’, P. fauriei, and P. ussuriensis survived exposure to −36°C (−32°F) in January of 1994.
Preference for and Suitability of Selected Elms, Ulmus spp. and Their Hybrids for the Elm Leaf Beetle, (Pyrrhalta luteola Coleoptera: Chrysomelidae)
Authors: Miller Fredric , Ware George 
Published: August 2020

Abstract
Selected elms Ulmus spp. and their hybrids growing at the Morton Arboretum, Lisle, IL were evaluated in the laboratory for feeding preference by the elm leaf beetle, Pyrrhalta luteola (Muller). Results from the single-choice and multiple-choice feeding studies showed that U. szechuanica was the least suitable for feeding and reproduction by the adult elm leaf beetle. The hybrids U. pumila x U. parvifolia and U. pumila x U. americana, and U. pumila (control) appeared to be highly suitable for feeding and reproduction by the adult elm leaf beetle. Adult longevity and the pre-ovipositional period appeared to be a function of suitability as adults feeding on U. szechuanica had the shortest longevity and the longest pre-ovipositional period. The converse was also true. Results from multiple-choice studies were consistent with the single-choice studies. The intermediately suitable species/hybrids of U. japonicawilsoniana x U. pumila, U. Japonica, U. macrocarpa, and U. wilsoniana show promise for further elm breeding programs. Further studies are needed to evaluate hybrid crosses of the intermediately and least preferred elms as potential sources of shade trees resistant to Dutch elm disease and not preferred by the elm leaf beetle.
Evaluation of Selected Herbicides on Field-Grown Woody Ornamentals
Authors: Reeder Jesse A. , Gilliam Charles H. , Wehtje Glenn R. , South David B. , Keever Gary J. 
Published: August 2020

Abstract
Six herbicides and selected combinations were evaluated on four field-grown woody landscape crops: live oak, ‘Mary Nell’ holly, ‘Chesapeake’ viburnum, and ‘Acoma’ crapemyrtle. All herbicide treatments provided excellent control of goosegrass (Eleusine indica (L.) Gaertn.). Treatments with Predict (norflurazon) provided adequate sicklepod (Cassia obtusifolia L.) control. Only Goal (oxyfluorfen)-containing treatments controlled cutleaf eveningprimrose (Oenothera laciniata Hill). Predict and Predict treatment-combinations bleached older foliage of crapemyrtle and viburnum when applied in the first year after planting; however, growth was not affected. Holly was not injured by any herbicide treatments. Pendulum (pendamethalin) and Surflan (oryzalin) had similar weed control activity and plant growth with no plant injury
Offset Stage of Development Affects Hosta Propagation by Stem Cuttings
Authors: Keever G.J. , Eakes D.J. , Gilliam C.H. 
Published: August 2020

Abstract
Offset stem cuttings of Hosta sieboldiana at different stages of development (SOD) were removed from mother plants previously treated with BA; half of the cuttings at each SOD were treated with 1000 ppm IBA prior to placing under intermittent mist. Rooting percentages, primary and secondary root counts, root lengths, root rating, root dry weights, and final shoot SOD were greater for cuttings removed at a more advanced SOD. Rooting was greater than 85% for cuttings with 3 unfurled leaves, the most advanced SOD in this study. Treatment of cuttings with IBA increased primary root counts by 35%, but did not affect other measured characteristics.
Influence of Inoculant Form and Applied Nitrogen on Growth and Root Nodulation of Maackia amurensis
Authors: Giridhar J. , Pai B. , Graves William R. 
Published: August 2020

Abstract
We studied growth and nodulation of Maackia amurensis Rupr. & Maxim, treated with three forms of an inoculant of Bradyrhizobium (USDA 4349) and irrigated with solutions containing N at 1.8, 3.6, 7.2, or 14.3 mol·m−3(25, 50, 100, or 200 ppm). One inoculant (arabinose-gluconate liquid) was prepared in our laboratory, whereas the other two (Cell-Tech liquid and Cell-Tech peat powder) were obtained from a commercial source. Nodule dry mass of 10-week-old seedlings was similar regardless of inoculant form. Only plants supplied N at 1.8 and 3.6 mol·m−3 (25 and 50 ppm) nodulated consistently, and nodule dry mass of plants in these two treatments was not different. Laminar area and plant dry mass were highest among plants provided the two highest concentrations of N. Shoot N content was lowest and highest for plants provided N at 3.6 mol·m−3 (50 ppm) and 14.3 mol·m−3 (200 ppm), respectively, and it was not affected by form of inoculant. We conclude that liquid and peat-based inoculants cause a similar degree of nodulation. This study also demonstrated that providing N at concentrations of 7.2 mol·m−3 (100 ppm) or higher inhibits nodulation, and that inoculation with USDA 4349 does not substitute for applied N if maximal early seedling growth is desired.
Stimulation of Basal and Axillary Bud Formation of Container-grown Hybrid Tea Roses
Authors: Jayroe-Cournoyer Linda , Newman Steven E. 
Published: August 2020

Abstract
Two plant growth regulators, 6-benzylaminopurine (BA) and sodium salt of 2,3,4,6-bis-O-(1-methylethylidene)-a-L-xylo-2-hexulofuranosonic acid [dikegulac-sodium (DS)], were applied separately to container-grown two-year-old hybrid tea rose cultivars ‘Honor’, ‘Peace’, ‘Tournament of Roses’, ‘Touch of Class’, and ‘Prima Donna’ to study the effects on basal and axillary shoot production. Four rates of BA (0,75,125 and 250 ppm) or DS (0,250,500 and 1000 ppm) were applied as drenching sprays to the graft union or with floral foam applied basally or to the top of a cut cane. ‘Tournament of Roses’ had the greatest number of basal shoots when BA was applied at 75 ppm to a cut cane with a floral cube. ‘Peace’ and ‘Prima Donna’ had the greatest number of basal shoots when BA was applied at 250 ppm to a cut cane with a floral cube. Axillary shoots increased on ‘Honor’ when BA was applied as a basal floral foam. DS increased axillary shoots for ‘Peace’ only when applied as a drenching spray to the bud union. Otherwise, DS did not increase basal shoots for any other cultivar regardless of application method and rate. Neither chemical nor application method consistently promoted basal and axillary shoots in all five cultivars.
Frequency of Drive (Quinclorac) Treatments on Common Bermudagrass Tolerance and on Large Crabgrass Control
Authors: Jack Johnson B. 
Published: August 2020

Abstract
When a postemergence (POST) herbicide is used to control large crabgrass [Digitaria sanguinalis (L.) Scop.] in common bermudagrass [Cynodon dactylon (L.) Pers.], the herbicide should maintain optimum weed control for 8 to 10 weeks without causing undesirable injury to the turfgrass. A field experiment was conducted during 1993 and 1994 to determine the lowest rate of Drive (quinclorac) needed to control large crabgrass without causing undesirable injury to bermudagrass turf. Drive (quinclorac) applied at 0.28 kg ai/ha (0.25 lb ai/A) initially in early May and repeated at the same rate at a 2-week interval, controlled 85% large crabgrass for 16 weeks in 1993 and 70% for 10 weeks in 1994. The control in 1994 was 96% for 17 weeks when the herbicide was applied at 0.28 kg ai/ha (0.25 lb ai/A) in each of three applications on May 2, May 29, and June 13. The maximum bermudagrass injury in 1993 from Drive (quinclorac) applied at 0.28 kg ai/ha (0.25 lb ai/A) in each of two applications at 2- to 4-week interval was ≤ 27% compared to ≥ 33% when ≥ 0.56 kg ai/ha (≥ 0.5 lb ai/A) was applied as a single application. Bermudagrass treated initially with Drive (quinclorac) at 0.28 kg ai/ha (0.25 lb ai/A) was injured higher in 1994 (≤ 35%) than in 1993 (≤ 14%). Bermudagrass injury was ≥ 40% when the second application was delayed until mid- to late June either year or when the herbicide was applied in three applications during May and June 1994.
Effect of 2,4-D and Triclopyr on Annual Bedding Plants
Authors: Hatterman-Valenti Harlene , Christians Nick E. , Owen Micheal D.K. 
Published: August 2020

Abstract
Greenhouse trials were conducted to evaluate annual flower response to simulated drift of Weedar 64 (dimethylamine salt of 2,4-D) and Turflon Amine (triethylamine salt of triclopyr). Mature annual flowers responded differently to low concentrations of Weedar 64 and Turflon. The order for species from most sensitive to least sensitive was petunia &gt; begonia = marigold =pansy =statice &gt; geranium =impatiens =rose periwinkle =salvia. Rates less than 128 g ae/ha (0.11 lb ae/A) caused only slight injury. Injury was expressed in reduced flower production and callus. Turflon suppressed flowering 19% more than Weedar 64. Both herbicides reduced flowering at rates greater than 100 g/ha (0.088 lb/A).
Efficacy of Three Nitrogen and Phosphorus Sources in Container-Grown Azalea Production
Authors: Warren Stuart L. , Bilderback Ted E. , Tyler Helen H. 
Published: August 2020

Abstract
Rooted stem cuttings of ‘Sunglow’ azalea (Rhododendron sp. ‘Sunglow’) were potted into 3.8 liter (#1) containers with a pine bark: sand (6:1 by vol) substrate and topdressed with 3.5 g (0.12 oz) N per container with resin-coated NH4 NO3 and P [Osmocote 18N–2.6P–10K (18–6–12)], urea and sulfur-coated P [Woodace 20N–1.8P–9.1K (20–4–11)], or composted turkey litter (CTL) [Sustane 5N–0.9P–3.3K (5–2–4)]. A container-grown plant production area was constructed and subdivided into nine separate plots, 7.6 × 1.8 m (25 × 6 ft), with a 2% slope and lined with black plastic. At 5:00 AM daily, 1.3 cm (0.5 in) of water was applied by overhead irrigation at a rate of 1.6 cm/hr (0.6 in/hr) resulting in a leaching fraction of approximately 0.1 to 0.2. All effluent was collected individually from each plot. At 8:00 AM daily, volume of effluent was measured and sub-sampled for analysis of NO3, NH4, and P. The experiment, a RCB design with 3 replications, was conducted for 100 days. Thirty containers were placed in each plot for a total of 90 containers per treatment. After 100 days, 13%, 12%, and 9% of the N applied was recovered in the effluent from containers fertilized with resin-coated NH4NO3, urea, and CTL, respectively. Of the P applied, 8%, 27%, and 15% was recovered in the effluent with resin-coated P, sulfur-coated P, and CTL, respectively. Resin-coated NH4NO3 and urea produced greater shoot growth and higher shoot N content compared to CTL. Shoot and root P contents were greatest with resin-coated P. Nutrient efficiency defined as grams of nutrient the plantabsorbed divided by total grams of nutrient found in effluent and plant resulted in resin-coated NH4NO3 and urea having the highest N efficiency (56%); while, resin-coated P had the highest P efficiency (43%).
Application of RAPD-PCR Markers for Identification and Genetic Analysis of American Elm (Ulmus americana L.) Selections
Authors: Kamalay Joseph C. , Carey David W. 
Published: August 2020

Abstract
We used randomly amplified polymorphic DNA (RAPD) markers from DNA polymerase chain reactions to differentiate selected American elms. DNA profiles made from leaf DNAs of parental trees were identical to profiles produced by DNA from leaves, roots, vascular tissues, callus or suspension-cultured cells from the same trees or their ramets. In addition, several variations in the technique did not appear to alter the genotype-specific DNA profiles from a given elm selection. RAPD polymorphisms were inherited as dominant Mendelian factors in the progeny of a cross between two American elm selections. We conclude that the construction of RAPD DNA profiles is a reliable and easy method for selection identification, genetic analysis, and the assembly of linkage maps in American elms.
Greenhouse Rose Production in Media Containing Coal Bottom Ash
Authors: Butler Susan H. , Bearce Bradford C. 
Published: August 2020

Abstract
Coal bottom ash was mixed with composted hardwood bark fines in proportions of 3:1, 2:1 and 1:1 (by vol) and with soil and peat in proportions of 1:1:1 (by vol). A mix of soil, sand and peat 1:1:1 (by vol) was used as the control root medium. Rosa × hybrida L. ‘Samantha’ plants were planted and cultured for one year and production indices recorded for four harvests. Flower stem lengths, flower bud diameters, production times, and numbers of flowers produced in media composed of ash and bark were equivalent to those in the control medium. Stem fresh weights of flowers produced in ash:bark media exceeded those in the control during third and fourth harvest. Foliar analysis showed increased B but decreased Mn and Cu in plants grown in the ash:bark media. Values of physical characteristics of all media were within acceptable ranges. Requirements for irrigation and fertilization were higher in the ash:bark media. The coal bottom ash:hardwood bark combinations showed potential as components of artificial root media for growing greenhouse roses.
Controlled Freezing of Twenty-three Container-grown Herbaceous Perennials
Authors: Herrick Todd A. , Perry Leonard P. 
Published: August 2020

Abstract
Twenty-three containerized herbaceous perennials were acclimated to ambient outdoor temperature and photoperiod until November 19, when they were moved into a greenhouse and held at 3C (37F) until February 15. At that time, plants were exposed for 30 minutes to a range of subzero temperatures, and returned to the greenhouse for forcing. Plants were rated for survival and salability following 6 weeks regrowth at 15C (59F), using a subjective scale of 1 to 5 (1 = worst, 5 = best, 3 and above considered salable). Of the 23 perennials studied, 15 survived after exposure to at least-8C (18F), however, 40% of the species and cultivars surviving at this temperature sustained a level of injury which rendered them unsalable. Most plants were rated salable at treatment temperatures 3 to 6 degrees warmer than their respective lowest survival temperatures (LST's). Phlox ‘Chattahoochie’, Phlox ‘Morris Berd’ and Tiarella ‘Laird of Skye’ remained salable after exposure to —11C (12F). Campanula takesimana, Heuchera americana ‘Dales Strain’, Penstemon fruticosus ‘Purple Haze’, Rosmarinus officinalis ‘Arp’, Tiarella ‘Running Tapestry’, and Tiarella cordifolia ‘Slick Rock’ remained salable after exposure to-8C (18F). Erodium reichardii ‘Roseum’, Hebe macrocarpa ‘Margaret’, and Verbena ‘Homestead Purple’ remained salable after exposure to-5C (23F). Only the unfrozen controls of Houttuynia cordata ‘Chameleon’ and Thelypteris kunthii remained salable. Treatment means for Ceratostigma plumbaginoides were not significantly different and all 6 Hibiscus cultivars (‘Blue River II’, ‘Disco Belle Pink’, ‘Disco Belle Rose Red’, ‘Disco Belle White’, ‘Lord Baltimore’ and ‘Southern Belle’) failed to survive any of the temperature treatments. In general, plants showed a gradual decline in salability with decreasing temperatures.
Generation and Identification of New Viburnum Hybrids
Authors: Hoch W.A. , Zeldin E.L. , Nienhuis J. , McCown B.H. 
Published: August 2020

Abstract
The controlled crossing of fragrant flowered viburnums (V. carlesii and its hybrids) with the hardier, rugose foliaged V. lantana is unattainable through traditional breeding methods due to incompatibilities within the developing seed. Hybrid plants from these crosses have now been obtained using embryo rescue techniques. Embryos were removed from developing seed 17 days following pollination and placed on WPM medium to promote continued maturation. Genotypes from two crosses, V. lantana ‘Mohican’ x V. carlesii ‘Aurora’ and V. lantana ‘Mohican’ x V. x juddii, were obtained and verified using RAPD markers. These plants are presently being evaluated for ornamental characteristics and cold hardiness.