Brief Summary of Minutes of Annual Meeting

Catherine Neal - Univ. of New Hampshire. Accomplishments: Completed a 3-year study of container production systems utilizing Syringa "Miss Kim" as the test species. Results clearly show superior growth of both tops and roots in below ground pot-in-pot and bag-in-pot systems compared with above-ground fabric and plastic containers. However, plants in above-ground fabric containers over-wintered very successfully whereas plants in plastic containers fared poorly. Similar results were observed in other trials with Viburnum plicatum Mariesii and Weigela florida, where all the above ground plastic container plants were winter-killed but the above ground fabric container plants survived. The positive response of plants to fabric containers is attributed to their effects on root morphology and distribution and on modifying temperatures during winter cold events as well as preventing radiant heating during the summer. James E. Klett  Colorado State University. Accomplishments: Woody and herbaceous plants continue to be evaluated for adaptability to the High Plains on a 30 ha site. Woody (95 taxa) and herbaceous plants (82 taxa) were acquired in 2007 for evaluation. Performance records for 3,300 taxa of woody and herbaceous plants were entered into a computer system, which are available on three websites. Over 1,150 varieties of annual flowers were grown and evaluated in 2007 and a performance report was published and sent to all cooperators and industry personnel in the state and region. Many vegetatively propagated annual varieties including argyranthemum, calibrachoa, coleus, geranium, New Guinea impatiens, osteospermum, petunia, and verbena have become very important bedding plant crops in the state, due to this research. In 2007, seven plant species were recommended or introduced by Plant Select®. In 2007, over 1.5 million Plant Select® labels were sold which is our best estimate of the number of Plant Select® plants sold. Over eighty demonstration gardens are displaying Plant Select® plants throughout Colorado. The multi-site woody plant trial continued at five locations throughout the state. Plants tested for five years are being evaluated and Cupressus arizonica from the 2002 planting will be a future Plant Select® recommendation. In 2008, seven additional plants are being recommended or introduced. Four herbicides: Mesotrione, Dinnethenamid, Sulfentrazone, and Dimethenamid Plus were evaluated for weed control effectiveness and phytotoxicity on six herbaceous plants with the experiment starting at three different times in Fort Collins. Sulfentrazone resulted in phytotoxicity, reduced dry weights, and some death with Echinacea purpurea. The drought tolerance study was continued in 2007 with extensive data taken on common lilac, three-leaf sumac, serviceberry, tall fescue, and Kentucky bluegrass. The tall fescue and Kentucky bluegrass showed physiological stress due to water. The shrub species with more extensive rooting systems only showed some minor stress at lower water treatments. A project determining herbaceous plant species and media type suitable to support green roofs in a semi-arid, high elevation area was initiated in 2007. William R. Graves  Iowa State University. Accomplishments: Propagated plants from a small population of Styrax americanus that is disjunct to the north from the primary distribution of this species. Genetic and physiological tests to assess the potential attributes of this northern germplasm are underway. Evaluated the genetic structure of Nyssa aquatica and examined the stress resistance of this species, which, to date, has not been examined for its horticultural value(in collaboration with J. Sharma). Assessed the capacity for Nyssa aquatica and Nyssa ogeche to be propagated asexually from stem cuttings (in collaboration with J. Sharma). Documented the overwintering capacity and landscape performance of two provenances of Callicarpa americana planted at five sites from Arkansas north to central Iowa. Continued to evaluate the horticultural potential of the three species of Dirca (Dirca palustris, Dirca mexicana, Dirca occidentalis), including research on propagation, stress physiology, and provenance variation in ornamental traits(in collaboration with J. Sharma). Studied interactions between Alnus maritima and Alnus nitida and the nitrogen-fixing Frankia that associate with these alders (in collaboration with J. Sharma and R. Hummel). Progressed toward the development of so-called bioplastic plant pots fabricated from zein, a protein from corn. Jyotsna Sharma  University of Florida. Accomplishments: Assessed mycorrhizal and genetic diversity of an endangered terrestrial orchid from the west coast. Piperia yadonii populations showed strong genetic differentiation even though all populations are located within 50 km from each other. Produced plants of Canna flaccida from seeds and tested them for Phosphorus uptake. Assessed nitrogen removal capacity of an artificial wetland at a plant nursery by studying the nitrogen dynamics and denitrification associated with plant rhizospheres. Assessed shade tolerance and nitrogen requirement of Callicarpa americana and Myrica cerifera. H. Brent Pemberton - Texas AgriLife Research, Texas A&M System. Accomplishments: Bedding plant greenhouse and garden performance trials were continued both for the spring and fall seasons with industry support. Also, an effort geared toward trials of new material for a mid-winter color market was continued. Several hundred entries were trialed from the major seed companies doing business in the U.S. Data from these trials were presented at Field Days and programs to target audiences. In addition, a web site for presentation of the results and images from the trials was updated and improved. Trials were continued in cooperation with the Dallas Arboretum. In addition, the number of accessions in the Research and Demonstration Garden was expanded showcasing roses that have been proven disease resistant in the Overton trials, perennial entries in the bedding plant trials, Texas Superstar (CEMAP) plants, and other plants showing potential for introduction to the Texas Greenhouse/Nursery industry. The award program called the North Texas Winners Circle was continued to denote the best performers of the bedding plant trials at the Overton Center, Dallas Center, and Dallas Arboretum locations. Also, work on the Texas Superstar Board continued and trials and promotions were accomplished. Continued role as Convener and Organizer of the Fourth International Rose Symposium which was held in Santa Barbara, California in September 2005. Served as Editor of a volume of Acta Horticulturae that serves as the published proceedings for the symposium. This work is now in print. Work continues on the installation of a model landscape to measure water use of several ornamental species in a landscape setting using soil moisture probes. This work is being done in cooperation with Dr. R. White (Soil and Crop Sciences, Texas A&M University). Secured funding from the federally funded IR4 program to study the effects of growth regulators on postharvest performance of several ornamental greenhouse species. These studies are being performed in cooperation with Dr. M. Reid (University of California, Davis) so that test plants can be subjected to actual shipping treatment by commercial carrier. Studied the effects of E-beam technology on geranium cuttings as a possible method of disease control in cooperation with W. Mackay (TAES - Dallas) and S. Pillai (E-beam facility - College Station). Irradiation from the E-beam killed the cuttings and a paper was published with the results. Secured funding and initiated studies on the efficacy of a new controlled release fertilizer product for bare-root forcing of dormant field grown roses. This study was completed and another study was completed for potted roses grown from liners. A study was initiated in cooperation with Dr. U. Schuch (University of Arizona) to study the water use of roses. Rooted cuttings are being grown in large pots to simulate a landscape situation. The study is being replicated at two locations to determine the effect of the climate differences between eastern Texas and southern Arizona. Stan Hokanson  University of Minnesota. Accomplishments: We continue to evaluate the Rosa germplasm remaining in the program including seedlings and advanced selections A testing agreement with Bailey Nurseries to evaluate UMNRosa 362, a red-flowered polyantha garden rose (w/ Kathy Zuzek). Polyantha rose selections UMNRosa 251, UMNRosa 215, and UMNRosa 320, named Rosa Northern Accents" Sven, Lena, and Ole respectively, are currently for sale in local nurseries and garden centers. Fifteen University of Minnesota advanced rose selections are being evaluated with Bailey Nurseries, Inc. at their testing sites across North America to determine how broadly adapted they are (w/ Debbie Lonnee, and Johnathan Pedersen, Bailey Nurseries). Current efforts with deciduous azalea breeding include production of seedlings with improved foliage quality, i.e. lower levels of powdery mildew and better fall color, later flowering, i.e. mid-June to August, and improved flower fragrance. Fourteen parental combinations were included in this years crossing with the primary goal of developing later flowering cultivars. Currently ~ 500 seedlings are being evaluated in the program. Approximately 400 of these were planted into seedling nurseries this spring. Nine selections have been made since 2002. We continue to evaluate a trial planting of several advanced selections of four maple taxa (17 genotypes) that was established at the NCROC in Grand Rapids, MN in May, 2004. Five of the six red and Freeman maple selections, including the programs newest introduction, FirefallTM maple, performed well at Grand Rapids. Two of the seven sugar maple selections experienced substantial cold injury at Grand Rapids and appear unsuitable for use in USDA zone 3a. Several other sugar maples experienced varying amounts of injury among replications, possibly due to microclimatic variations in temperature and / or soil drainage. Plantings of these same maple genotypes were also established at the University of Minnesota Landscape Arboretum (Chanhassen), UMORE Park (Rosemount), Bachmans Production Nurseries, and Laws Nursery, Inc. (Lakeville). The later plantings will give us information regarding how well the trees grow and respond in a production setting(w/ Steve McNamara, Shengrui Yao, John Daniels, Bachmans, Inc. and Tim Power, Laws Nurseries). We continue to evaluate Weigela florida seedlings resulting from crosses between larger statured, cold hardy cultivars Red Prince and White Prince and the less cold-hardy, dwarf cultivar Minuet at the HRC. Bailey Nurseries has signed testing agreements to evaluate 15 selections from these populations. We are currently evaluating over 700 seedlings resulting from crosses between our initial F1 selections and the dwarf cultivar Minuet (w/ Steve McNamara, Debbie Lonnee, and Jonathan Pedersen, Bailey Nurseries, Inc.). We signed an exclusive license agreement with Bailey Nurseries, Inc. to market and sell the Betty Matthews clone of Kentucky Wisteria. Plant sales are expected to begin no later than 2011. New plantings of seedlings populations of Lacebark elm (Ulmus parvifolia) and Bald cypress (Taxodium distichum) were established at Grand Rapids in 2007 for cold hardiness evaluation. Cornelian cherry (Cornus mas) and sweetgum (Liquidambar styraciflua) populations established at Grand Rapids in 2005 suffered extensive cold damage with the sweetgums being completely killed-off. Approximately ten Cornelian cherry genotypes which suffered little to no damage are being vegetatively propagated for futher testing. A full years data on a planting of 650 Ribes aureum var. villosum (Clove Currant) seedlings, derived from 13 maternal parents established in May, 2006 at the Horticultural Research Center has been collected. The species, native to the upper Great Plains, is noted for its early season display of bright yellow, clove-scented flowers. We have identified families with a propensity for early flowering, disease resistance, and repeat bloom. Individual plants have been noted for these traits. At least one more year of data will be collected before selections are made for parental and cultivar potential. Efforts continue to identify and characterize black spot resistance genes in Rosa germplasm. Three tetraploid (cultivated) rose populations have been phenotyped for black spot resistance. Two of these populations are currently being evaluated with bulk segregant analysis in order to identify markers more closely linked to the resistance genes. Marker development for the BSA analysis was based on resistance gene analog sequences developed in collaboration with Dr. Thomas Debener at the University of Hannover in Germany. Tetraploid and diploid populations segregating for partial resistance to the three races of black spot disease have been developed. They will be analyzed to determine levels of specific or general combining ability. We have secured all the rose black spot races that have been reported and cultured around the world. We have obtained rose genotypes used in these various race differentiation tests. We have designed a new host differential array amalgamated from members of the previous tests. We will be running the races across the new array to standardize our current understanding of the rose black spot race situation in the world. The information will allow for a more concerted effort in black spot resistance gene identification and mapping efforts. With some recently obtained grant funding, we have initiated a study of the epidemiology of the fungal pathogen Cryptodiaporthe canker. This pathogen incites the golden canker disease in Pagoda dogwood (Cornus alternifolia). The disease is the primary limiting factor to Pagoda dogwood gaining significance in the upper Midwest Landscape Nursery industry. We have collected canker samples from several diseased Pagoda dogwood trees in Minnesota and have cultured the fungus. Spore trapping and rotating uninfected disease-free trees under infected trees through the growing season (April-October) should provide critical information on the spore dispersal cycle, infection timing, and disease development. Results should allow for the development of best management practices for the nursery industry. We also intend to develope a high-throughput screening protocol for identification of resistant germplasm (w/ Jenny Juzwik, USDA Forestry/Plant Pathology, Bob Blanchette, Plant Path., Kathy Zuzek). We have concluded experiments designed to determine the cause of stunting, necrosis, and distorted growth exhibited by river birches growing in artificial growing media. These symptoms showed-up as we attempted to screen birch germplasm for elevated pH tolerance. Experiments to determine the cause have included insect exclusion, manipulation of soil types, investigations into the role of soil microorganisms, and the role of various micro- and macronutrients. Interestingly, similar symptoms have been detected in pecan orchards, where symptoms are alleviated with Ni treatments. Mineral soils and Ni treatments alleviated the BAGS symptoms in our experiments (w/ Steve McNamara, Carl Rosen, Soil Sciences). With funding obtained from the Minnesota Nursery Landscape Association we have been collecting data and setting-up experiments designed to determine the relative invasiveness of introduced maple species (in comparison to native maples) and elucidate life history and reproductive biology traits which contribute to invasiveness. This is the second season in which we have made flower and seed counts for one to three genotypes of seven Acer species. Seed has been collected and tested for viability for each of these genotypes. Seed lots for each have been put into several storage regimes to test for dormancy requirments and viability. Seed is being sown in seven landscape environments to test for invasive potential. Long-term experiments are planned to evaluate persistence in different environments and reproductive success of these plants (w/ Steve McNamara). With some grant funding we have initiated a germplasm evaluation of some woody plant species with potential as sources of cellulosic derived ethanol. Alnus or alder species are nitrogen-fixing woody plants capable of growing on water saturated soils and nutrient poor soils which have never been used for food production. If alders capable of growing on such soils were found to produce ethanol profitably, they should be of some benefit to society. Finding key collaborators, Ulrike Tschirner  Bioproducts, Andy David  Forest Products, and Dean Current  CINRAM, was the key to obtaining the funding that is allowing us to pursue this research. We have established 4 of 6 proposed research sites this year. Our graduate student is evaluating mature wood samples of several Alnus, Salix, and Populus species for wood structure and ethanol yield. We hope to establish a correlation between yields in younger seedlings in the test plots and mature samples(w/ Ulrike Tschirner, Will Kusch, BioProducts/Andy David, Forest Products/Dean Current, CINRAM). Rolston St. Hilaire - New Mexico State University. Accomplishments: Micropropagated bigtooth maple (Acer grandidentatum) plants and tested their responses to short term radiation stress (Ph.D. Clare Bowen-OConnor, 2008). Evaluated the genetic diversity among selected provenances of bigtooth maples using simple sequence markers (sabbatical in the USDA-ARS lab in Beltsville, Maryland, 2007). Completed the evaluation of water use of contrasting designed landscapes used in urban desert environments (M.S. student, Victoria Frietze). Started the evaluation of weatherbased irrigation controllers (Ph.D student, Malik Aljouni). Developing a methodology for categorizing urban landscape types (Ph.D student, Malik Aljouni). Evaluating the impacts of climate change on selected New Mexico crops (Ph.D student, Salman Al Kofahi). Roger Kjelgren - Utah State University. Accomplishments: Working with nursery industry in the Intermountain West on developing pot-in-pot system for production of native plants. Looking at expanding to small farm/organic growers to add pot-in-pot native production of slower growing native woody species on contract basis. Jim Sellmer - Penn State University. Accomplishments: Pennsylvania researchers have developed a screening method for challenging Tusga species for susceptibility to hemlock woolly adelgid (HWA). Employing the challenge, they have confirmed the resistance of Tsuga chinensis (Chinese hemlock). Results of that research have been accepted for publication in the Journal of Arboriculture and Urban Forestry. A similar challenge protocol has been employed in evaluation of elongate hemlock scale (EHS) on hemlock. Preliminary data suggests that the system works for other scale insects. White pine weevil management research has demonstrated initial success in attracting and trapping adults using an alpha-pinene lure over that of a conventional alcohol/gum turpentine evaporative lure during a year in low white pine weevil presence/pressure. Janet Cole  Oklahoma State University. Accomplishments: Research on control of anthracnose caused by Colletotrichum gloeosporioides on Euonymus fortunei has been ongoing for several years. This research has shown that most fungicides are not effective in controlling anthracnose symptoms, but mancozeb reduces symptoms. Better control has been achieved by changing crop management practices. Plants grown under shade have less anthracnose symptoms than plants grown in full sun. Plants sprinkler irrigated during the afternoon generally have less symptoms that those that are sprinkler irrigated in the morning. Hannah Mathers  Ohio State University. Accomplishments: A multi-state survey of the United States (US) nursery/ landscape industry, worth $147.8 billion (Bn), generating 1.9 million (Mn) jobs and having an annual payroll of over three billion dollars was conducted in 2006-07 to gather information such as labor use, demographics and employment characteristics previously not collected. The lack of information was unpredicted considering over 40% of production costs and 20 to 39% of gross sales go to labor, and labor shortages, immigration reform and legal status of employees are widely reported as the US nursery/ landscape industry=s most critical issues. A total of 4466, self administered questionnaires (SAQs) containing 31 questions and 139 variables were sent in the summer of 2006, to nurseries [large (20 acres or more) and 15 medium (5 to 19 acres), i.e. 16.5 employees/ site] in each of nine states, Ohio, Michigan, Delaware, Tennessee, Florida, Indiana, Kentucky, Arizona and Rhode Island and 1548 SAQs were returned and analyzed (34%). Hispanics constituted 70% of nursery workforce, 57% from Mexico, and were the dominant group in all states except Indiana. The average employee age was 18-34, 41.7% had completed high school, 75% earned $6 to 10/ hr, 70% lacked health insurance and labor retention was less than 50% after five. For a long time, industry felt that split bark was an environmental problem, driven mainly by cold temperatures. But we were receiving reports of split bark in warmer parts of the country, such as Georgia, the Carolinas and California. Why would it be a cold issue if split bark is happening in those areas? Winter temperatures are part of the problem, but only because glyphosate weakens the bark structure enough to cause the trunks to split under stress. There's a large body of national research that supports those findings. Our research on the role of glyphosate and bark cracking has resulted in our teaming up with agricultural company, Monsanto, to help develop a glyphosate product that is safer to use for weed control around landscape and nursery woody plants. Dr. Mathers at OSU has been leading national public research on the impacts of glyphosate on woody plants, as well as educational efforts on which glyphosate products to use and how to properly apply the chemical in nursery/landscape settings. Gary Kling - University of Illinois. Accomplishments: Finished up a joint research project with Hannah Mathers with the publication of a joint article (see below). This project was a direct result of cooperation facilitated by our participation in the WERA-058. Finished the first phase of a research project on planting depth on Green ash, White ash, Thornless common honeylocust and Norway maple in which liners were planted at three depths (root flare at grade, root flare 6 or 12 below grade) and the trees grown for 2 years in a high quality nursery soil. At the end of 2 years, planting depth produced no differences in root dry mass within each species. Increasing depth however, resulted in increased trunk caliper for White ash and Norway maple. Quality ratings of the root systems (a function of number and branching) decreased for the deepest planted White ash but was unchanged in the other species. Norway maple had a decreasing root density with increasing depth and the deepest trees had roots that altered their original direction, turning to grow upward toward the surface. Additional replications of these treatments have remained in the ground and have now been grown a total of 5 seasons  data to be collected fall of 2008, followed by transplanting to landscape sites. Chris Starbuck - University of Missouri. Accomplishments: Research in collaboration with Dan Struve, Hannah Mathers, Bob Tripepi and others has documented that trees and shrubs of a number of species can be successfully transplanted bare root in summer using the Missouri Gravel Bed method. Recent work has shown that adding calcined clay to the gravel root growth medium improves plant growth in the gravel bed relative to the original mix containing 10% sand. Incorporating calcined clay also reduces the frequency of fertilization and irrigation required to maintain plants in the bed in good condition. Art Cameron - Department of Horticulture Michigan State University. Accomplishments: We conducted research on new crops including tender and hardy herbaceous and woody perennials. We determined photoperiod and vernalization requirements for several species and cultivars including Aquilegia Winky, Astilbe Astary Mix, Campanula Merrybells, Coreopsis Jethro Tull, Helianthus Table Mountain, Heliopsi Tuscan Sun and Lupinus Gallery Blue. Specific studies were also conducted on several selections of Coreopsis. We have continued studies on select tropical plants grown as summer annuals in Michigan including several cultivars of Colocasia, Musa and Xanthosomas. We have investigated vernalization and short day substitution for vernalization in Coreopsis Sunray. We concluded and published several studies on vernalization of Veronica Red Fox, Laruentia Beths Blue, and Dianthus Baths Pink.Several trade publications on new crop development were written and published.

Klett, J. E. 2007. 2006 Annual Winners. ColoGreen 23(1) 59-60. Klett, J. E. 2007. Plant Select® for 2007. ColoGreen 23(2) 64-65. Klett, J. E. 2007. Superior Herbaceous Perennials. ColoGreen 23(3) 52-54. Klett, J. E. 2007. Container Weed Control. ColoGreen 23(4) 48-49. Klett, J. E. 2007. The Root of the Matter. ColoGreen 23(5) 54-55. Klett, J. E. 2007. Plant Select® Update. ColoGreen 23(6) 50-51. Klett, J. E., Litus, Gl., And Ounsworth, M. 2007. Woody Plant Drought Study. Looseleaf 24(1) 16. Klett, J. E. 2007. More Unusual Woody Plants from Research Plots. Looseleaf 24(2) 10-11. Klett, J. E. 2007. Superior Herbaceous Perennials from Research Plots. Looseleaf 24(3) 10-11. Ounsworth, M. and Klett, J. E. 2007. The Root of the Matter. Looseleaf 24(4) 8. Klett, J. E. 2007. 2008 Plant Select®. Looseleaf 24(5) 12-13. Klett, J. E. 2007 Best 2007 Annual Flower Trials. Looseleaf 24(6) 6-7. Klett, J. E., Staats, D., and Brescher. 2007. Colorado State University 2007 Annual Flower Trial Garden Performance Report. 207p. Klett, J. E., Staats, D., Howlett, T., and Rogoyski, M. 2008. Weed Control and Phytotoxicity Following Pre-emergence Herbicide Applications to Container-grown Herbaceous Plants. J. Environ. Hort. 26(1) 39-44. Klett, J. E. and MacDonald. 2007. Multi-site Woody Plant Evaluation in Colorado. Hort. Science 42(4) 995. (Abstract) Howlett, T., Staats, D., and Klett, J. E. 2007. Efficacy and Phytotoxicity of Pre-emergence Herbicides in Container-grown Landscape Plants. Hort Science 42(4) 877. (Abstract) Peterson, B.J., W.R. Graves, and J. Sharma. 2008. Color of pubescence on bud scales conflicts with taxonomic keys for identifying species of Dirca L. Thymelaeaceae). Rhodora: in press. Graves, W.R. 2008. Habitat and reproduction of Dirca mexicana. Rhodora: in press. Sharma, J., J.A. Schrader, and W.R. Graves. 2008. Ecology and phenotypic variation of Leitneria floridana (Leitneriaceae) in disjunct native habitats. Castanea: in press. Schrader, J.A. and W.R. Graves. 2008. Nodulation and growth of Alnus nitida and Alnus maritima inoculated with species-specific and nonspecific Frankia. Journal of Environmental Horticulture 26:29-34. Schrader, J.A., M.A. Kroggel, and W.R. Graves. 2007. Nodulation and nitrogen-fixing capacity of rhizobial isolates from China in symbiosis with Maackia amurensis. Journal of Environmental Horticulture 25:47-50. Mickelbart, M.V.*, G.S. Bender, G.W. Witney, C. Adams, and M.L. Arpaia. 2007. Effect of clonal rootstocks on Hass avocado yield components, alternate bearing, and nutrition. Journal of Horticultural Science and Biotechnology 82:460-466. Mickelbart, M.V.*, S. Melser, and M.L. Arpaia. 2007. Salinity-induced changes in ion concentrations of Hass avocado trees on three rootstocks. Journal of Plant Nutrition 30:105-122. Teixeira, E.I.*, D.J. Moot, and M.V. Mickelbart. 2007. Seasonal patterns of root C and N reserves of lucerne crops (Medicago sativa L.) grown in a temperate climate were affected by defoliation regime. European Journal of Agronomy 26:10-20. Mickelbart, M.V.*, S. Larsen, R. Heath, and M.L. Arpaia. 2007. Changes in photosynthesis during flush development in avocado (Persea Americana Mill.). HortScience 42(4):992. Mickelbart, M.V.*, N. Wasmer, S. Revankar, and L. Collier-Christian. 2007. Effects of supplemental sulfur on growth of three woody ornamental species. HortScience 42(4):994. Yoo, C.Y.*, J.B. Jin, K. Miura, Y. Hua, M. Gosney, M.V. Mickelbart, R.A. Bressan, and P.M. Hasegawa. 2007. Ca2+/CaM signaling through AtGTL1 mediates drought stress adaptation. Plant Physiology, Plant Biology 07, Final Program and Abstract Supplement p. 108. Sharma, J., J.A. Schrader, and W.R. Graves. 2008. Ecology and phenotypic variation of Leitneria floridana (Leitneriaceae) in disjunct native habitats. Castanea. In Press. Peterson, B.J., W.R. Graves, and J. Sharma. 2008. Color of pubescence on bud scales conflicts with taxonomic keys for identifying species of Dirca L. (Thymelaeaceae). Rhodora: in press. Funderburk, J.E, L.A. Mound, and J.Sharma. 2007. Thysanoptera associated with native, terrestrial orchids in northern Florida and southern Georgia. Journal of Entomological Science 42(4):573-581. Sharma, J., Ishida, M.L.***, and V.L. Yadon. 2007. Mycorrhizal diversity of an endemic terrestrial orchid. Lankesteriana 7(1-2): 215-218. Sharma, J. and A. Bolques. 2007. Nutrient profile of runoff water at commercial plant nurseries in southeastern U.S. Proceedings of Southern Nursery Association Research Conference 52:29-33. Sharma, J., P.C. Wilson, and T.H. Yeager. 2008. Remediation of Runoff: Options for Container Plant Nurseries. 8pp. ENH-1088, Institute of Food and Agricultural Sciences, University of Florida. Sharma, J., A.V. Ogram, and A. Al-Agely. 2007. Mycorrhizae: Implications for Environmental Remediation and Resource Conservation. 5pp. ENH-1086, Institute of Food and Agricultural Sciences, University of Florida. Funderburk, J.E., S. Diffie, J. Sharma, A. Hodges, and L.S. Osborne. 2007. Thrips of ornamentals in the southeastern US. Gainesville, Florida: University of Florida, EDIS. 6 pp. ENY-845, Institute of Food and Agricultural Sciences, University of Florida. Sharma, J. 2008. Why Worry About Runoff at Container Plant Nurseries: Part II. 18 February. Sharma, J. 2007. Why Worry About Runoff at Container Plant Nurseries: Part I. 9(13). 10 September. Byrne, D.H., N. Anderson, and H.B. Pemberton. 2007. The use of Rosa wichuraiana in the development of landscape roses adapted to hot humid climates. Fourth International Symposium on Rose Research and Cultivation. Acta Horticulturae 751:267-274. Pemberton, H.B. and U.K. Schuch. 2007. Relationship between visually determined starch content and flowering of containerized field-grown garden roses. Fourth International Symposium on Rose Research and Cultivation. Acta Horticulturae 751:105-109. Shupert, D., D.H. Byrne, and H.B. Pemberton. 2007. Inheritance of flower traits, leaflet number, and prickles in roses. Fourth International Symposium on Rose Research and Cultivation. Acta Horticulturae 751:331-335. Pemberton, H.B., editor. 2007. Proceedings of the fourth international symposium on rose research and cultivation. Acta Horticulturae 751. International Society for Horticultural Science. Leuven, Belgium. 512 pages. Mackay, W.A., H.B. Pemberton, J. Maxim, and S. Pillai. 2008. Ionizing irradiation using electron beam to control importation of biothreat agents in geranium cuttings inhibits rooting. HortScience 43(3):955-956. Pemberton, H.B. 2008. An alternative method for analyzing landscape performance rating data. HortScience 43(4):1295 (Abstr.). Whitaker, V.M., K. Zuzek, and S.C. Hokanson. 2007. Resistance of 12 rose genotypes to 14 isolates of Diplocarpon rosae Wolf (rose blackspot) collected from eastern North America. Plant Breeding 126:83-88. Whitaker, V.M., J.M. Bradeen, and S.C. Hokanson. 2007. Distribution of rose blackspot (Diplocarpon rosae Wolf) genetic diversity in eastern North America using AFLP and implications for resistance screening Journal of the American Society for Horticultural Science 132:534-540. Whitaker, V.M., K. Zuzek, J.M. Bradeen, and S.C. Hokanson. 2007. Culturing and long-term storage of virulent races of the rose blackspot pathogen Diplocarpon rosae Wolf. Acta Horticulturae 751:199-205. Zuzek, K. and S.C. Hokanson. 2007. Shrub rose breeding at the University of Minnesota. Acta Horticulturae 751:291-298. Zlesak, D., K. Zuzek, and S.C. Hokanson. 2007. Rose pollen viability over time at varying storage temperatures. Acta Horticulturae 751:337-343. Khalil, S.D., R. St. Hilaire, M. OConnell and J. Mexal. 200x. Horticulturists can grow moonshine yarrow on a limited moisture budget. J. Environ. Hort. In Press. Bsoul, E., R. St. Hilaire, and D. VanLeeuwen. 2007. Bigtooth maples from selected provenances effectively endure deficit irrigation. Hortscience: 42:1167-1173. Bowen-OConnor, C.A., R. St. Hilaire, J. Hubstenberger, C.A. Baca, and D.M. VanLeeuwen. 2007. In vitro propagation of Acer grandidentatum Nutt. In vitro Cellular and Developmental Biol. 43: 50-60. Cardoso, G., T. Cerny-Koenig, R. Koenig, and R. Kjelgren. 2007. Characterizing fertilizer and media pH requirements for greenhouse production of Intermountain West native herbaceous perennials. Native Plant J..8:115-121. Zollinger, N., R. Koenig, T. Cerny-Koenig, and R. Kjelgren. 2007. Relative salinity tolerance of Intermountain Western United States native herbaceous perennials. HortScience 42:529-534. *Kjelgren, R. 2007. Agricultural experiment station faculty and administrator attitudes and perceptions regarding placing research results on the Internet. HortTechnology 17:95-101. Wehry, R.H., K.M. Kelley, R.D. Berghage, and J.C. Sellmer. 2007. Capturing Consumer Preferences and Interests in Developing a State Plant Promotional Program. HortScience 42(3): 574-580 Conklin, J.R. and J.C. Sellmer. 2007. Evaluating the Invasiveness of Norway Maple Cultivars. Pennsylvania Landscape and Nursery Magazine, Pa. Landscape and Nursery Association 53(2):28-34. Cole, J.T. and J.C. Cole. 2007. Tolerance of lilyturf (Liriope muscari) and four perennial ornamental grasses to preemergent herbicides. J. Applied Hort. 9:31-36. Boyer, C.R., J.C. Cole, and K.E. Conway. 2007. Effectiveness of copper sulfate pentahydrate, mancozeb, and hydrogen dioxide in controlling anthracnose on wintercreeper euonymus. J. Environ. Hort. 25:21-26. Acuna, A., and Mathers, H. M. 2008. Implementing and assessing an Onsite bilingual educational program for Hispanic nursery workers in Ohio. Journal of Environmental Horticulture. Accepted (In Press). Acuna, A., and Mathers, H. M. 2008. Nursery Worker Turnover and Language Proficiency. HortScience. (In review). Samatani, J. B., Kling, G. J., Mathers, H. M., and Case, L. T. 2007. Rice hulls, leaf-waste pellets and pine bark as herbicide carriers for container-grown woody ornamentals. HortTechnology. 17:289-295. Mathers, H. M., Lowe, S. B., Scagel, C., Struve, D. K., and Case, L. T. 2007. Abiotic factors influencing root growth of woody nursery plants in containers. HortTechnology. 17:151-162. Case, L. T., and Mathers, H. M. 2006. Herbicide Treated Mulches for Weed Control in Ornamentals. Journal of Environmental Horticulture 24:84-90. Stoven, A.A., H.M. Mathers, D.K. Struve. 2006. Fertilizer application method affects growth, nutrient and water use efficiency of container-grown shade tree whips. HortScience 41:1-7. Scagel, C., and Mathers, H. M. 2008. Root Death. American Nurserymen 207(2): 26-28, 30, 33-34. Mathers, H. M. 2008. Trees On Crack. Nursery Management & Production. July issue. Mathers, H. M., Case, L. T., and Rivera, D. 2007. An ace up your sleeve. American Nurserymen 206(11): 36-38,40,42-44,46. Mathers, H. M. 2007. Recognize herbicide injury. Nursery Management & Production. 23(4):50-52, 54, 56, 60. Bohnert. C.A., C. Starbuck and S. Anderson. 2008. Amending a Gravel Based Growing Medium with Calcined Clay Improves Physical Properties and Seedling Growth. J. Environ. Hort. 26:149-56 In Press. Kirk, Steven, D.; Starbuck, Chris J.; Van Sambeek, J.W. 2005. Missouri Gravel Bed and a Pot-in-Pot system superior to white polyethylene and foam for overwintering Syringa pubescens subsp. patula liners. In: The International Plant Propagators' Combined Proceedings 54: 516-521. Starbuck C., D.K. Struve and H. Mathers. 2005. Bareroot and balled-and-burlapped red oak and green ash can be summer transplanted using the Missouri Gravel Bed System. HortTechnology. 15:122-127. Fausey, B.A. and A.C.Cameron. 2007. Differing vernalization responses of Veronica spicata Red Fox and Laurentia axillaries. Jour. Amer. Soc. Hort. Sci. 132:751-757. Cameron, A.C., S.R. Padhye, and C.M. Whitman. 2007. The control of flowering in herbaceous perennials. Proc. IC on Qual. Manag. Supply Chains of Ornamentals Eds.: S. Kanlayanarat et al. Acta Hort. 755, 113-119. Padhye, S.R., B.M. Cregg and A.C. Cameron. 2007. Chilling sensitivity of stored purple fountain grass propagules. Postharvest Biol. Tech. 49:235-240. Padhye, S.R. and A.C. Cameron. 2007. Dianthus gratianopolitanus Vill. Baths Pink has a Near-Obligate Vernalization Requirement. HortScience. 43 (2):346-349.