Brief Summary of Minutes of Annual Meeting

A summary of accomplishments at the participating institutions is presented below: At Michigan State University, research and outreach was conducted on production and flowering of herbaceous perennials and establishment of green roof technology. Cameron spent 6 months in Australia on sabbatical leave working in landscape ecology related to Eucalyptus distribution related to germination requirements. In Oklahoma, during the 2006 growing season, we completed the second growing season for several research projects. Most of the research studied the effect of various fungicides on control of anthracnose caused by Colletotrichum gloeosporioides on wintercreeper euonymus (Euonymus fortunei). This research confirmed the results of previous studies that showed the most fungicides tested are ineffective in controlling anthracnose on wintercreeper euonymus. Mancozeb decreases but does not eliminate disease symptoms while other fungicides tested including thiophanate methyl and chlorothalonil provide little disease suppression. Cultural practices including growing containerized plants on black plastic sheeting rather than on gravel and periodic application of sodium hypochlorite to the surface of the growing area around the containers were also ineffective at reducing disease symptoms. At the University of Minnesota, following research and extension activity was conducted. Plant breeding and cultivar development. Rosa: We have terminated further crosses in the breeding effort. We will continue to evaluate the currently existing germplasm which includes; seedlings from last years crosses that will be planted out this spring and summer, seedling blocks in the ground at the Horticultural Research Center, and eight additional selections in regional trials at Grand Rapids, Morris, and Rosemount, MN. (w/ Kathy Zuzek). We have signed an exclusive license with Bailey Nurseries, Inc. to market and sell 3 polyantha rose selections (Rosa 251, Rosa 215, Rosa 320). These have been trademarked as Northern Accents Sven", Ole", and Lena", respectively. Approximately 2,000 plants of each will be available for commercial sales this summer. We currently have 17 advanced rose selections in regional trials, i.e. Grand Rapids, Morris, Rosemount, Minn. Fifteen University of Minnesota advanced rose selections are currently being evaluated with Bailey Nurseries, Inc. at their testing sites across North America to determine how broadly adapted the selections are. (w/ Debbie Lonnee, and Johnathan Pedersen, Bailey Nurseries, Inc.). Rhododendron: 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. Approximately 300 seedlings which had been evaluated for the last three years in containers were planted into seedling blocks in Spring 2007. No new crosses were made in 2006. Nine selections have been made since 2002. Eight selections are in production/propagation trials with Mountain Shadow Nursery, Inc. AZ 619 - Wine red flower color, good foliage, AZ 353  Orange/Pink/Raspberry blend, AZ 554 - Red flower color, good foliage, AZ 362  Double-flowered yellow, fragrant, AZ 430  Orange/Burnt orange blend, floriferous, AZ 626 (2005 selection)  Soft tangerine/peach, AZ 625 (2005 selection)  Large-flowered double, cream/pink/orange blend, AZ 493  Double-flowered, fragrant pink. When we have clones propagated, all will be moved into an advanced second test replicated trial (w/ Steve McCulloch, Mountain Shadow Nursery). Acer: A trial planting of several advanced selections of four maple taxa (17 genotypes) was established at the NCROC in Grand Rapids, MN in May, 2004. One and two-year old grafted trees were established in three replicate completely randomized plantings. The winter climate at Grand Rapids will enable a more rapid assessment of cold tolerance than has been possible in Chanhassen in recent years. In addition, the planting should allow us to ascertain the suitability of the selections for USDA zone 3 landscapes. Acer platanoides x A. truncatum hybrids were completely killed at Grand Rapids where midwinter temperatures fell to 48 F (-44 C) in January 2005. However, these hybrids were the best-performing trees at the dry and windy UMORE Park trial site, suggesting they may be valuable trees for harsh urban planting sites in USDA zone 4. Our nursery cooperators are very impressed with the hybrids. 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. (Farmington and Lakeville, MN respectively). The later plantings will give us information regarding how well the trees grow and respond in a production setting. These plantings represent the first commercial nursery trials the project has ever undertaken (w/ Steve McNamara, Shengrui Yao, John Daniels, Bachmans, Inc. and Tim Power, Laws Nurseries). In all likelihood, the large tree breeding program along with any other taxon for which we can not propagate clonal plants in house will be phased out over the next 3-5 years. The variability created with unknown rootstocks and time and effort needed to manage these long-term programs are too great given our current staffing and budget situation. Other taxa: Bailey Nurseries, Inc. has signed an exclusive license to market and distribute our Wisteria macrostachys clone Betty Matthews. A trademark name and marketing plan will be presented in March. Plants should be commercially available in 2008. 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. This summer, staff from Bailey Nurseries made 15 selections from the plot and testing agreements were signed to allow them to continue advanced testing. In 2006 crosses were made between selections from the initial F1 populations and backcrosses were made to Minuet. Over 700 seedlings from these crosses were planted for field evaluations this spring (w/ Steve McNamara, Debbie Lonnee, and Jonathan Pedersen, Bailey Nurseries, Inc.). A field evaluation consisting of 13 half-sib families of Ribes aureum var. villosum (Clove currant) was established at the HRC in May 2006. Seed was obtained from the National Clonal Germplasm Repository in Corvallis, Oregon. Surprisingly, no named cultivars of Clove currant exist, considering the bright yellow, early spring flower display and the rich, heavy clove fragrance emitted by the flowers. Plants are being evaluated for form, size, flower phenology, productivity, and disease resistance (w/ Steve McNamara). Seed collections of Lindera benzoin (Spice bush) were made in October in southwestern Michigan. In addition, 500 seedlings derived from seed collected in wild populations in Ottawa County, Michigan have been potted and are being grown on for field evaluation. Spice bush is a shade tolerant understory shrub native to USDA Plant Hardiness Zone 5 locations in the eastern U.S., not including Minnesota. Broken twigs emit a pleasant spicy odor. Early spring, yellow flowers result in a brilliant scarlet colored fruit in September/October. No named cultivars currently exist in the industry. (w/ Steve McNamara) Plant Disease Research Rosa black spot disease. For the past five years we have been involved in investigations of rose black spot disease. Publications resulting from Vance Whitakers masters thesis work describe culturing, long-term storage, race and molecular diversity of the black spot disease of rose, Diplocarpon rosae. Black spot is the most significant disease of rose worldwide. Vance Whitaker began work on his Ph.D. in January 2006. In February, 2006 he applied for and was awarded an NSF Central European Summer Research Institute Science and Engineering Fellowship to study with Dr. Thomas Debener, one of the worlds foremost experts on rose blackspot resistance genetics, in Hannover, Germany. Our current efforts involve a candidate gene approach to identifying black spot resistance genes in rose germplasm. We are targeting resistance gene analogs (RGAs). A number of RGAs have been identified and sequenced. Current efforts involve development of markers based on the RGA sequences to screen rose germplasm for additional resistance genes (w/ Jim Bradeen, Plant Pathology). Cryptodiaporthe canker: We have initiated a project to identify resistance to this disease in Pagoda dogwood (Cornus alternifolia). The canker disease is the primary limiting factor to Pagoda dogwood gaining significance in the upper Midwest Landscape Nursery industry. Currently we have collected seed from native populations extending from Zone 2 locations in Northern Minnesota to Zone 4 locations in the seven county metropolitan region of Minnesota. We have also canker samples from several diseased Pagoda dogwood trees in Minnesota and have cultured the inciting organism, Cryptodiaporthe corni. We have re-initiated efforts to develop seedling screening protocols which will allow us to begin the first efforts to develop canker resistant Pagoda dogwoods. In addition we are developing plans to study the epidemiology of the pathogen (w/ Jennifer Juzwik, USDA Forest Service/Plant Pathology). Environmental Stress Research - Birch abnormal growth syndrome. 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. Results will be submitted in a manuscript (w/ Steve McNamara, Carl Rosen, Soil Sciences). Cold hardiness screening. Every year beginning in October we begin testing woody plants for cold hardiness in programmed freezer tests. Beginning in October allows us to evaluate the particular plants acclimation process. January tests allow us to determine a particular plants mid-winter hardiness. Continued testing through April allow us to evaluate a particular plants de-acclimation process. We routinely test advanced selections from our breeding program, azalea, rose, trees, and various shrubs. Information from the tests is used in the selection process. Ultimately, the information is used to describe new cultivars to the nursery industry. Periodically we test groups of cultivars from various species that are relatively unknown in the upper Midwest. In 2005 and 2006 we tested new and relatively unknown Clethra and Weigela cultivars respectively. A number of new cultivars, with unknown cold hardiness, from both species are showing up in garden centers in Minnesota. The Weigela florida cultivar Midnight Wine has proven quite winter tender for local growers, despite claims to the contrary from the hybridizers. Results from our freezer tests should allow the local industry to determine not only how cold hardy the cultivars are, but also in what part of the winter problems develop (w/ Steve McNamara). At Utah State University, the investigators continued work on water use of shade trees in contrasting humid and arid climates. Also conducting work on cultivar development in Eriogonum corymbosum, a small, late-blooming shrub native to the Intermountain West that has wide variability in flower color, plant size, crown form, and leaf size and color. Purdue University representatives determined factors resulting in bark cracking of ornamental woody species. (with Hannah Mathers, The Ohio State University). Their continuing project includes evaluation of elms resistant to Dutch Elm Disease (with Cliff Sadof, Purdue Univ. Dept of Entomology), and identification and evaluation of cold hardy American snowbell (Styrax americanus) for landscape plantings in northern climates (with Sally Weeks, Purdue Dept of Forestry and Eric Oesterling, Penn State Extension Agent, Westmoreland Co., Pa.). Preliminary research at the University of New Hampshire showed that certain species of plants produced and over-wintered above ground in fabric containers may survive whereas plants in plastic containers have a high mortality rate. Testing of several species shows a lack of correlation between root and shoot cold hardiness of woody shrubs. Carbohydrate analyses of fall root samples showed a higher level of glucose in Viburnum trilobum roots in fabric containers compared to plastic; root mass was also significantly higher of plants over-wintered and grown on for an additional growing season. Prototype insulating pot covers are being tested and increased plant survival over uncovered plants in 2006-07. University of Illinois reported that organic mulches treated with pre-emergent herbicides (Diuron and Surflan) were found to provide equal or better weed control of Poa annua (annual bluegrass), Senecio vulgaris (common groundsel), and Capsella bursa-pastoris (shepherds purse) in containers than when applied with water as a carrier. The organic carriers with herbicide sprays gave efficacy visual ratings equivalent to water as a carrier and at the same time provided a reduction in phytotoxicity of the Diuron on Hetz Midget American arborvitae. Pine bark treatments increased crop plant biomass for Goldflame Japanese spirea as compared with no organic mulch treatments. Landscape leaf-waste pellets as a carrier produced equivalent efficacy and phytotoxicity ratings to conventional spray application of pendimethalin and prodiamine on both chrysanthemum and wintercreeper. The leaf-waste pellets were not an effective carrier for isoxaben. In addition, bare-root liner plants of four taxa of common landscape trees, Acer platanoides, Fraxinus Americana, Fraxinus pennsylvanica, and Gleditsia triacanthos inermis, were planted in the field at three depths to determine the effect of planting depth on tree performance. Planting depths included: 1) the first branch root just below the surface, 2) the first branch root 15 cm below the surface and 3) 30 cm below the surface. Stem caliper and shoot and root growth were measured over two seasons. After two seasons of growth, increasing depth increased the caliper of the white ash, honeylocust and maple. The dry mass of the roots of white ash increased with planting depth. Root density ratings decreased with increasing depth for the green ash, white ash, and Norway maple. The most shallow plants required staking to maintain their upright position in the first season. Texas A&M University accomplishments included: (1) 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 at cooperative sites at the Dallas Center and 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. Development of a new 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; (2)continued role Convener and Organizer of the Fourth International Rose Symposium which was held in Santa Barbara, California in September 2005. Also served as Editor of a volume of Acta Horticulturae that will serve as the published proceedings for the symposium. This work is now completed and at the publisher; (3)funding was secured and planning done for 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). Equipment is installed and tested with the remaining installation to be done in fall of 2007; (4)secured funding from the federally funded IR4 program to study the effects of growth regulators on postharvest performance of several ornamental greenhouse and woody species; (5) 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). At the University of Florida, a water conservation workshop was presented at ASHS in collaboration with colleagues from the nation; a constructed wetland system was assessed for its efficacy in removing nitrogen from nursery runoff; and native woody species were assessed for nitrogen uptake and shade tolerance (in collaboration with Dr. Mack Thetford, UF). Penn State University reported that Pennsylvania researchers continue to evaluate the susceptibility of Tsuga species for susceptibility to Hemlock Woolly Adelgid and Elongate Hemlock Scale through direct challenges in the field and under greenhouse settings. In addition, research is underway to evaluate selected Abies for adaptability to diverse climatic and environmental conditions across USDA Hardiness Zones 5 and 6. Research results are being finalized for publication by a PhD candidate on the invasive potential of Acer platanoides and Viburnum opulus cultivars. White pine weevil management research on trapping methods, growth degree day confirmation, and pesticide efficacy trials continue. University of Missouri accomplishments included a greenhouse study in which seedlings of Gymnocladus dioicus were grown in mixtures of pea gravel with 0, 10, 20, 30 or 40% (v/v) calcined clay with or without 10% sand. After 18 weeks in the gravel media, seedling growth was quantified by measuring height, caliper and dry weights of roots and tops. As in the previous study, seedlings grown in mixtures containing more than 10% calcined clay were larger than those grown in unamended mixtures. Gymnocladus seedlings grown in pea gravel containing 30% TerraGreen were more than three times as tall and 1.6 times greater in stem caliper than those grown in unamended gravel. In 2006, the greenhouse study was repeated and the effects of incorporating calcined clay on porosity and water holding characteristics were quantified. This research showed that addition of calcined clay to a gravel based growing medium significantly increased the water holding ability of the medium while maintaining acceptable air-filled porosity and confirmed the growth enhancement observed previously. University of Arkansas reported that The University of Arkansas Plant Evaluation program, initiated in 1999, has evaluated over 115 woody ornamental plants at three trial locations across Arkansas representing the three climatic zones. Results from these evaluations are reported at state, regional, and national meetings and in trade publications. Annual reports are distributed to participants in the trial. Annual reports, plant growth data, and photographs are maintained on a University website. Annually, the industry is provided with a brief written program summary and list of potential nursery sources. This summary provides an efficient means for the wholesale industry to obtain this plant material. University of Idaho member was involved in three studies. The first study found that 2-0 plug seedlings of pinyon pine (Pinus edulis) and subalpine fir (Abies lasiocarpa) could be grown successfully in field or gravel beds and under 55% shade. Fir seedlings survived best if they received the shade treatment compared to full sun. In another study, pinyon pine and subalpine fir seedlings grew well in fabric and plastic containers, with fir seedlings producing significantly more roots if grown in fabric bags. In the third study, switchcane can be micropropagated by single-node rhizome sections if roots are attached to the explant. In addition, culm explants grew better in liquid or half-strength phytagel medium rather than regular agar at full strength (0.6%).

Zollinger, N., R. Koenig, T. Cerny-Koenig, and R. Kjelgren. 2007. Relative salinity tolerance of Intermountain Western United States native herbaceous perennials. HortScience 42(3):529-534. Kjelgren, R. 2007. Agricultural Experiment Station Faculty and Administrator Attitudes and Perceptions Regarding Placing Research Results on the World Wide Web HortTechnology 17:95-101 Kjelgren, R., and T. Cerny-Koenig. 2006. Evaluating a line source irrigation system for determining water requirements of herbaceous perennials . J. Environ. Hort. 24:225229. Cardoso, G., R. Kjelgren, Teresa Cerny-Koenig, and Rich Koenig. 2006. Pot-in-pot production of six Intermountain West native herbaceous perennial species grown in containers. J. Environ. Hort. 24: 77-83. Montague, T, and R. Kjelgren. 2006. Use of thermal dissipation probes to estimate water loss of containerized landscape trees. J. Environ. Hort. 24:95-104. Zollinger, N., R. Kjelgren, T. Cerny-Koenig, K. Kopp, and R. Koenig. 2006. Drought responses of six ornamental herbaceous perennials. Scientia Horticulturae, 109:267-274. Dewey, D., P. G. Kjohnson, and R. Kjelgren. 2006. Effects of irrigation and mowing on species diversity of grass and wildflower mixtures for the Intermountain West. Native Plant J. 7:267-278. 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. 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.*, P. Chapman, and L. Collier-Christian. 2006. Endogenous levels and exogenous application of glycinebetaine to grapevines. Scientia Horticulturae 111:7-16. 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. 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. [Abstract] 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. [Abstract] 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. [Abstract] Gosney, M.J. and M.V. Mickelbart*. 2006. Measuring water loss in Thellungiella halophila. The Biology of Transpiration: From Guard Cells to Globe, October 10-14, 2006, Snowbird, Utah. [Abstract] Moot, D.J.*, E. Teixiera, H.E. Brown, and M.V. Mickelbart. 2006. Changes in total biomass and N content of taproots of alfalfa crops under contrasting defoliation frequencies. 40th North American Alfalfa Improvement Conference and 19th Trifolium Conference, July 16-19, 2006. Ramada Inn Airport at Mall of America in Bloomington, Minnesota, USA. [Abstract] http://www.naaic.org/meetings/national/2006meeting/proceedings/clovers&medicago.htm Mickelbart, M.V. 2007. Horticulture and global warming. Indiana Nursery and Landscape News 67(4):32. Mickelbart, M.V. 2007. Is vitamin B1 useful when transplanting? Indiana Nursery and Landscape News 67(3):34. Mickelbart, M.V. 2007. Pruning and tree caliper. Indiana Nursery and Landscape News 67(2):36. Mickelbart, M.V. 2006. Managing for minimal losses in the event of Sudden Oak Death infestation. Indiana Nursery and Landscape News 66(6):30-31. Mickelbart, M.V. 2006. Tree planting depth and mulch. Indiana Nursery and Landscape News 66(4):34. Dennis, J.H. and M.V. Mickelbart. 2006. Risk management principles IV: Financial risk. Indiana Nursery and Landscape News 66(4):26-28. Mickelbart, M.V. 2006. Is there enough bark to meet landscape demands? Indiana Nursery and Landscape News 66(3):36 Dennis, J.H. and M.V. Mickelbart. 2006. Risk management principles III: Human risk. Indiana Nursery and Landscape News 66(3):34-35. Mickelbart, M.V. 2006. How do plants respond to warm winters? Indiana Nursery and Landscape News 66(2):38. Dennis, J.H., B. Taylor, and M.V. Mickelbart. 2006. Risk management principles II: Marketing risk. Indiana Nursery and Landscape News 66(2):32-34. Mickelbart, M.V. 2006. Deer control in nurseries and landscapes. Indiana Nursery and Landscape News 66(1):34. Dennis, J.H., B. Taylor, and M.V. Mickelbart. 2006. Risk management principles I: Production risk. Indiana Nursery and Landscape News 66(1):32-33. Mickelbart, M.V. and J. Beckerman. 2006. What you need to know about P. ramorum. American Nurseryman 204(10):20-23. Dennis, J.H. and M.V. Mickelbart. 2006. Decreasing marketing risk. Ohio Florists Association Bulletin, May/June Issue, Number 896. Neal, Catherine. 2006. Winter Survival of Shrubs in Fabric Containers in a Zone 5 Climate. Proc. SNA Research Conference 51: 52-54. Neal, Catherine and Richard C. Beeson. 2007. Viburnum Root Mass and Fall Carbohydrate Levels as Affected by Container Type. HortScience 42 (4): 862. Neal, Catherine, Jeffrey Schloss, Stanley Swier, John Roberts, Margaret Hagen, Amy Ouellette, Sadie Puglisi, Mary Tebo and Lauren Chase-Rowell. 2007. Landscaping at the Waters Edge: an Ecological Approach. Univ. of New Hampshire Cooperative Extension, Durham NH. 92 pgs. Klett, J.E. 2006. Superior Annuals. Colo Green 22 (1) 52-54. Klett, J.E. 2006. Unusual Woody Plants. Colo Green 22 (2) 61-62. Klett, J.E. 2006. Underused Woody Plants. Colo Green 22 (3) 61-62. Klett, J.E. 2006. Proven Herbaceous Perennials. Colo Green 22 (4) 61-62. Klett, J.E. and MacDonald, R. 2006. Plant Select® Woody Plant Trials. Colo Green 22 (5) 61-62. Klett, J.E. 2006. More Unusual Woody Plants from Research Plots. Looseleaf 23 (1) 18. Ounsworth, M. and Klett, J.E. 2006. Water Requirements of Landscape Shrubs and Turfgrass. Looseleaf 23 (2) 8. Klett, J.E. 2006. Plant Select® for 2007. Looseleaf 23 (4) 12-13. Ounsworth, M. and Klett, J.E. 2006. Drought Avoidance and Drought Tolerance. Looseleaf 23 (5) 12-13. Klett, J.E. 2006. Superior Annuals from the 2006 Trials. Looseleaf 23 (6) 12-13. Litus, G. and Klett, J.E. 2006. Drought Stress and Recovery in Green Ash. HortScience 41 (4) 1009 (Abstract). Harris, J. R. 2007. Transplanting large trees. CAB Reviews: Perspectives in Agriculture, Veterinary Science, Nutrition and Natural Resources 2007 2, No. 024 Richardson-Calfee, L.E., Harris, J.R., and Fanelli, J.K. 2007. Posttransplant root and shoot growth periodicity of sugar maple. J. Amer. Soc. Hort. Sci. 132:147-157. Day, S.D., and Harris, J.R. 2007. Fertilization of red maple (Acer rubrum) and littleleaf linden (Tilia cordata) trees at recommended rates does not aid tree establishment. Arboric. Urb. For. 33: 113-121. Samtani, J.B., G. J. Kling, H.M. Mathers, and L. Case. 2007. Rice hulls, leaf-waste pellets, and pine bark as herbicide carriers for container-grown woody ornamentals. HortTechnology: 17(3):289-295. Samtani, J.B., G. J. Kling, and D. J. Williams. 2006. Leaf-waste pellets as a herbicide carrier for container-grown ornamental plants. Weed Tech. 20:942-949. Schuch, U.K., H.B. Pemberton, and J.J. Kelly. 2007. Post harvest moisture loss from bare-root roses affects performance of containerized plants. HortScience 42(3):622-625. 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. In Press. 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. In Press. 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. In Press. Pemberton, H.B. and R.I. Cabrera. 2006. Fourth international symposium on rose research and cultivation. Chronica Horticulturae 46(2):33-34. Pemberton, H. Brent and W.R. Roberson. 2007. Effects of plant growth regulators on branching and growth of azalea and rose. HortScience 42(4):939-940 (Abstr.). Pemberton, H. Brent and W.R. Roberson. 2007. Effects of plant growth regulators on postharvest characteristics of geranium and impatiens. HortScience 42(4):925 (Abstr.). Denny, G., M. Arnold, W. Mackay, L. Lombardini, and H.B. Pemberton. 2007. Effect of provenance on drought tolerance of Taxodium distichum. HortScience 42(4):911 (Abstr.). 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: 40-50. Bsoul, E., R. St. Hilaire, and D. VanLeeuwen. 2007. Bigtooth maples from selected provenances effectively endure deficit irrigation. Hortscience 42: 11671173. VanLeeuwen, D., R. St. Hilaire and E. Bsoul. 2006. Statistical analysis of mixed model factorial experiment with missing factor combinations: The case of asynchronous cyclic drought data. J. Amer. Soc. Hort. Sci. 131: 201-208. Bsoul, E., R. St. Hilaire, and D. VanLeeuwen. 2006. Bigtooth maples exposed to asynchronous cyclic irrigation show provenance differences in drought adaptation mechanisms. J. Amer. Soc. Hort. Sci. 131:459-468. Hurd, B., R. St. Hilaire, and J. White. 2006. Residential landscapes, homeowner attitudes and water-wise choices in New Mexico. HortScience 16: 241-246 Kelley, K.M., J.R. Concklin, J.C. Sellmer, and R.M. Bates. 2006. Invasive Plant Species: Results of a Consumer Awareness, Knowledge, and Expectations Survey Conducted in Pennsylvania. Journal of Environmental Horticulture 24 (1) 53-58. Durhman, A.K., D.B. Rowe, and C.L. Rugh. 2007. Effect of substrate depth on initial growth, coverage, and survival of 25 succulent green roof plant taxa. HortScience 42(3):588-595. Getter, K.L. and D.B. Rowe. 2007. Effect of substrate depth and planting season on Sedum plug establishment for green roofs. J. Environ. Hort 25(2):95-99. Durhman, A.K., D.B. Rowe, and C.L. Rugh. 2006. Effect of watering regimen on chlorophyll fluorescence and growth of selected green roof plant taxa. HortScience 41(7):1623-1628. Getter, K.L. and D.B. Rowe. 2006. The role of green roofs in sustainable development. Hort Science 41(5):1276-1285. Rowe, D.B., M.A. Monterusso, and C.L. Rugh. 2006. Assessment of heat-expanded slate and fertility requirements in green roof substrates. HortTechnology 16(3):471-477. 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 132:532-540. Whitaker, V.M., K. Zuzek, J.M. Bradeen, and S.C. Hokanson. Culturing and long-term storage of virulent races of the rose blackspot pathogen Diplocarpon rosae Wolf. Acta Horticulturae Zuzek, K. and S.C. Hokanson. Shrub rose breeding at the University of Minnesota. Acta Horticulturae Zlesak, D., K. Zuzek, and S.C. Hokanson. 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Proceedings of Southern Nursery Association Research Conference 51: 544-548. Sharma, J., D.Z. Haman, and R.C. Beeson. 2006. Water-conserving and runoff-reducing production systems for containerized plants: Some examples of recently developed technologies. 4 pp. EHN-1048, Institute of Food and Agricultural Sciences, University of Florida. Marshall-Mattson, K. and J. Sharma. 2006. An annotated bibliography of all literature and reports on Platanthera praeclara. Document of the US Fish and Wildlife Office, Minneapolis, Minnesota. 2006. Rain Gardens. 8(8). 10 April. UF NFREC Newsletter. Knox, G.W. and J. Sharma. 2006. Propagation Protocols for Yellow-flowered Cultivars of Magnolia. Dearing, GA: The Center for Applied Nursery Research. 2 pp. http://www.canr.org/Knox%20MagnoliaRooting%20F-05.pdf Sharma, J. and M.H.S. Light. 2006. 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