bluuebunny/crossref_metadata_2025 huggingface dataset:
Bleeding Heart: A Review for Growers
Authors: Hodges Laurie
Published: December 2018

A favorite garden flower for centuries, bleeding heart or old-fashioned bleeding heart (Lamprocapnos spectabilis) is also used as a potted plant and in floral arrangements. Most general gardening guides include information on growing conditions but provide few specifics regarding plant growth and development that are important to those interested in commercial cultivation and use in the floral industry. Although uncommon in the U.S. floral industry, the plant is adaptable for use as a flowering potted plant and as cut floral stems with potential for year-around availability. This report provides detailed cultural information for this audience with an overview of the history of the species and its unique characteristics. Despite the popularity of the spectacular flower and plant form, until 1997 it was only available in the common pink and white form or a pure white form and exhibited little phenotypic variability. Three new cultivars, Goldheart, Valentine, and Hordival, are now available with distinctive foliage and flower colors. These new cultivars are poised to create much interest among gardeners and cut flower growers. The history, culture, propagation, forced flowering, use as a cut flower, pest management, and pharmacological potential are presented.
Lettuce Yield and Quality When Grown in High Tunnel and Open-Field Production Systems Under Three Diverse Climates
Authors: Wallace Russell W. , Wszelaki Annette L. , Miles Carol A. , Cowan Jeremy S. , Martin Jeffrey , Roozen Jonathan , Gundersen Babette , Inglis Debra A.
Published: December 2018

Field studies were conducted during 2010 and 2011 in Knoxville, TN; Lubbock, TX; and Mount Vernon, WA; to compare high tunnel and open-field organic production systems for season extension and adverse climate protection on lettuce (Lactuca sativa) yield and quality. The climates of these locations are diverse and can be typified as hot and humid (Knoxville), hot and dry (Lubbock), and cool and humid (Mount Vernon). In both years, 6-week-old lettuce seedlings of ‘New Red Fire’ and ‘Green Star’ (leafy type), ‘Adriana’ and ‘Ermosa’ (butterhead type), and ‘Coastal Star’ and ‘Jericho’ (romaine type) were transplanted in the late winter or early spring into subplots covered with black plastic and grown to maturity (43 to 65 days). Lettuce harvest in Knoxville occurred at 50 to 62 days after transplanting (DAT), with open-field lettuce harvested an average of 9 days earlier compared with high tunnel plots both years (P > 0.0001). The earlier than anticipated harvests in the open-field in Knoxville in 2010 were due to lettuce bolting. In Lubbock, high tunnel lettuce was harvested an average 16 days earlier in 2010 compared with open-field lettuce (P > 0.0001), while in 2011, high temperatures and bolting required that open-field lettuce be harvested 4 days earlier than lettuce grown in high tunnels. On average, lettuce cultivars at Mount Vernon matured and were harvested 56 to 61 DAT in 2010 and 54 to 64 DAT in 2011 with no significant differences between high tunnel and open-field production systems. Total and marketable yields at Mount Vernon and Lubbock averaged across cultivars were comparable in both high tunnel and open-field plots. At Knoxville, although total yields were significantly higher (P > 0.0062) in high tunnels than open-field plots, incidence of insect, disease, and physiological damage in high tunnel plots reduced lettuce quality and marketable yield (P > 0.0002). Lettuce head length:diameter ratio (LDR) averaged across cultivars was equal between high tunnel and the open field at all three locations. High tunnel production systems offer greater control of environments suitable for lettuce production, especially in climates like Knoxville and Lubbock where later-planted open-field systems may be more susceptible to temperature swings that may affect lettuce quality. These results suggest that although high tunnel culture alone may influence lettuce yield and quality, regional climates likely play a critical role in determining the impact of these two production systems on marketable lettuce yields.
Performance of Southern Highbush Blueberry Cultivars Under High Tunnels in Florida
Authors: Santos Bielinski M. , Salame-Donoso Teresa P.
Published: December 2018

A study was conducted over two southern highbush blueberry (Vaccinium corymbosum × Vaccinium darrowi) seasons in a grower field in Florida. The objective was to compare the early fruit weight of southern highbush blueberry cultivars in high tunnels and in open fields. Four treatments were tested using combinations of two southern highbush blueberry cultivars (Snow Chaser and Springhigh) and two production systems (open fields and 18-ft-high tunnels). The results indicated that there was a significant effect of the production systems on the number of days with air temperatures at or near freezing (≤34 °F), and maximum and minimum air temperatures. The minimum air temperature in open-field plots reached ≈19 and 21 °F (61 freezing or near-freezing events) in the 2009–10 and 2010–11 seasons, respectively, whereas the minimum air temperatures inside the high tunnels were ≈32 and 33 °F, respectively, during the same seasons (only 3 days at ≤34 °F). This indicated that using high tunnels was an effective means to avoid freezing air temperatures in blueberries. In the first season, the cumulative early fruit weight was the highest in plots planted with ‘Snow Chaser’ inside the high tunnels (≈10 tons/acre), while the combined production of the two cultivars in the open fields did not reach 1 ton/acre until the end of the early harvests. The following year, there were no differences in the cumulative early fruit weight of both cultivars when planted in the open fields (2.2 tons/acre) and the cumulative fruit yields of ‘Springhigh’ and ‘Snow Chaser’ growing inside the high tunnels was twice and four times higher, respectively, than the early fruit production obtained in the open fields. These data showed the profound effect of high tunnels on flower protection and fruit set. High tunnels reduced water use for freeze protection. The total volume used in the open fields during the freezing or near-freezing days was ≈2.5 acre-inch/acre per 8 hours of freeze protection, whereas only 1/10 of that volume was applied inside the structures.
Screening of New Mexico Autumn-sown Onions for Black Mold Disease
Authors: Kamal Neel , Saxena Ashish , Steiner Robert L. , Cramer Christopher S.
Published: December 2018

Black mold, caused by the fungus Aspergillus niger, is one of the major postharvest onion (Allium cepa) diseases causing qualitative and quantitative losses. To screen autumn-sown onion cultivars for black mold resistance, 12 cultivars were sown in 2004 and 2005 in Las Cruces, NM. Percent sporulated area, disease severity, and disease incidence were recorded after 2 and 4 weeks of storage. ‘Texas Early White’ exhibited less disease symptoms than other cultivars tested. For all cultivars, disease symptoms in terms of severity and incidence increased as bulbs were stored for longer periods of time.
Developing a Vegetable Fertility Program Using Organic Amendments and Inorganic Fertilizers
Authors: Ozores-Hampton Monica
Published: December 2018

This review integrates information from common organic amendments used in conventional vegetable production, including 1) cover crops (legumes and nonlegumes), 2) compost generated from yard wastes, biosolids, municipal solid waste (MSW), animal manures, and other biodegradable waste by-products, and 3) raw animal manure (with and without bedding). Environmental monitoring has shown elevated nitrate concentration to be widespread in both surface and groundwater, often occurring in regions with concentrated horticultural production. Therefore, the objective of this review was to calculate the nutrient content from organic amendments, since these are not considered nutrient sources. Common organic amendments affect soil bulk density, water-holding capacity, soil structure, soil carbon content, macro- and micronutrients, pH, soluble salts, cation exchange capacity (CEC), and biological properties (microbial biomass). The first step in building a conventional tomato (Solanum lycopersicum) fertility program will be to take a soil sample and send it to a soil laboratory for a nutrient analysis. These results should be compared with the local crop recommendations. Second, select the organic amendments based on local cover crop suitability and availability of compost, raw animal manure, or both. Then, determine the nutrients available from cover crops and other applied organic amendments and use inorganic fertilizer sources to satisfy the crop nutrient requirements not supplied from these other sources.
Survey of Physical, Chemical, and Microbial Water Quality in Greenhouse and Nursery Irrigation Water
Authors: Meador Dustin P. , Fisher Paul R. , Harmon Philip F. , Peres Natalia A. , Teplitski Max , Guy Charles L.
Published: December 2018

The objective was to analyze the physical, chemical, and biological water quality in horticulture irrigation systems in 24 ornamental plant greenhouses and nurseries in the United States. At each greenhouse or nursery, water was collected from up to five points (“Sample Types”) which included 1) “Source” from municipal or private well supplies, 2) “Tank” from enclosed storage containers, 3) “Subirrigation” from water applied to crops in ebb-and-flood systems, 4) “Furthest Outlet” that were irrigation emitters most distant from the Source, and 5) “Catchment Basin” from open outdoor retention areas. On average, Source water had the highest physical and microbial quality of Sample Types including the highest ultraviolet (UV) light transmission at 86%, lowest total suspended solids (TSS) at 3.1 mg·L−1, and lowest density of aerobic bacteria with 1108 cfu/mL of water. Average quality of recycled water from Subirrigation or Catchment Basins did not meet recommended levels for horticultural irrigation water for UV transmission (68% to 72% compared with recommended 75%), microbial counts (>100,000 cfu/mL compared with recommended <10,000 cfu/mL), and chemical oxygen demand (COD) (48.2 to 61.3 mg·L−1 compared with recommended <30 mg·L−1). Irrigation water stored in Tanks or applied at Furthest Outlets had lower physical and biological water quality compared with Source water. Level of aerobic bacteria counts highlighted a risk of clogged microirrigation emitters from microbial contaminants, with highest bacteria levels in recirculated irrigation water. The physical, chemical, and microbial water quality results indicate a need for more effective water treatment to improve biological water quality, particularly with recirculated irrigation.
Establishment and Performance of Bluegrass Species and Tall Fescue under Reduced-input Maintenance in a Temperate Mediterranean Environment
Authors: Fiorio Stefano , Macolino Stefano , Leinauer Bernd
Published: December 2018

Turfgrass water conservation has become important in many parts of the world, including the transition zones of Mediterranean Europe. Species selection is considered one of the most important factors influencing turfgrass water use, and drought-tolerant cool-season species are encouraged to be used in areas where long dormancy periods of warm-season grasses is unacceptable. A field study was conducted from Mar. 2007 to Sept. 2009 at Padova University, Italy, to evaluate establishment and performance of nine turfgrass cultivars under reduced-input maintenance. The study included hybrid bluegrass (Poa pratensis × P. arachnifera) cultivars Solar Green, Thermal Blue, and Thermal Blue Blaze; kentucky bluegrass (Poa pratensis) cultivars Cocktail, Cynthia, and Geronimo; and tall fescue (Festuca arundinacea) cultivars Apache, Murray, and Regiment. Establishment rate was assessed after two seeding dates (20 Mar. and 20 Sept.), and grasses were subsequently fertilized with 15 g·m−2 nitrogen per year and irrigated once every 2 weeks at 40% of reference evapotranspiration from June to August. Turfgrass and weed cover were estimated 60 days after seeding (DAS), and turf quality was evaluated weekly on a scale of 1 (worst) to 9 (best). Normalized difference vegetation index (NDVI) was measured weekly during 2009. Tall fescue cultivars exhibited greater quality than hybrid bluegrass or kentucky bluegrass, under both spring and autumn seeding. Hybrid bluegrass had similar quality to kentucky bluegrass cultivars, although they performed well only when sown in autumn. Our results suggest that among the tested grasses, tall fescue performed better under the reduced irrigation in a Mediterranean transition zone climate than kentucky bluegrass or hybrid bluegrass.
Response of Asparagus to Repeated Application of Residual Herbicides
Authors: Zandstra Bernard H. , Morse Sylvia , Tocco Rodney V. , Morrice Jarrod J.
Published: December 2018

Asparagus (Asparagus officinalis) is a perennial crop that has a 12- to 20-year production life in the field. Herbicides are applied in the spring each year and again after final harvest in early summer. Asparagus yield declines with age, and herbicides may contribute to yield decline. An experiment was established in 2004 and maintained for seven years with the same herbicide treatments applied each spring to determine herbicide effects on marketable spear yield. Spring-applied diuron, metribuzin, terbacil, sulfentrazone, halosulfuron, mesotrione, and clomazone had no adverse effect on yield or quality over the seven years of the experiment. Flumioxazin reduced yearly average marketable yield compared with standard treatments, and some spears developed lesions early in the season after rainfall. Asparagus yield from most treatments declined more than 50% from 2004 to 2010.
Comparison of Intracanopy Light-emitting Diode Towers and Overhead High-pressure Sodium Lamps for Supplemental Lighting of Greenhouse-grown Tomatoes
Authors: Gómez Celina , Morrow Robert C. , Bourget C. Michael , Massa Gioia D. , Mitchell Cary A.
Published: December 2018

Electric supplemental lighting can account for a significant proportion of total greenhouse energy costs. Thus, the objectives of this study were to compare high-wire tomato (Solanum lycopersicum) production with and without supplemental lighting and to evaluate two different lighting positions + light sources [traditional high-pressure sodium (HPS) overhead lighting (OHL) lamps vs. light-emitting diode (LED) intracanopy lighting (ICL) towers] on several production and energy-consumption parameters for two commercial tomato cultivars. Results indicated that regardless of the lighting position + source, supplemental lighting induced early fruit production and increased node number, fruit number (FN), and total fruit fresh weight (FW) for both cultivars compared with unsupplemented controls for a winter-to-summer production period. Furthermore, no productivity differences were measured between the two supplemental lighting treatments. The energy-consumption metrics indicated that the electrical conversion efficiency for light-emitting intracanopy lighting (LED-ICL) into fruit biomass was 75% higher than that for HPS-OHL. Thus, the lighting cost per average fruit grown under the HPS-OHL lamps was 403% more than that of using LED-ICL towers. Although no increase in yield was measured using LED-ICL, significant energy savings for lighting occurred without compromising fruit yield.
A Web-based Geographic Information System Application for Description of American Viticultural Areas in Texas
Authors: Takow Elvis A. , Hellman Edward W. , Birt Andrew G. , Tchakerian Maria D. , Coulson Robert N.
Published: December 2018

A geographic information system (GIS) application was developed containing 18 layers of spatially explicit environmental data relevant to characterization of the eight officially recognized American Viticultural Areas (AVAs) for wine grape (Vitis vinifera) production in Texas. GIS climate variables included daily minimum temperature, daily maximum temperature, daily average temperature (TAVG), growing degree days (GDD), ripening period mean temperature (RPMT), annual precipitation, solar radiation, vapor pressure, and number of frost days. Soil attributes were texture, depth, available water capacity, pH, permeability, and bulk density. These data were used to develop interpretative descriptions of Texas AVAs published on the Winegrowing Regions of Texas web site, which also serves as the public portal to the interactive GIS (AVATXIS). Individuals can use AVATXIS to access data and visualize spatial variability on maps to characterize Texas AVAs for any or all of the environmental factors and to examine spatial relationships among factors.
Survival, Frost Susceptibility, Growth, and Disease Resistance of Corkbark and Subalpine Fir Grown for Landscape and Christmas Trees
Authors: Barney Danny L. , Bauer Michael , Jensen Jennifer
Published: December 2018

Trees from six corkbark fir (Abies lasiocarpa var. arizonica) and 10 subalpine fir (A. lasiocarpa var. lasiocarpa) seed sources were grown at the University of Idaho Sandpoint Research and Extension Center (SREC), Sandpoint, ID, and two commercial nurseries in Idaho and Oregon. Posttransplant mortality was highest during the first two years. After six growing seasons, survival averaged 76% and 80% for corkbark and subalpine fir, respectively. In SREC irrigated plots, survival averaged 96% and 99% for corkbark and subalpine fir, respectively. Spring frost damage occurred annually on 66% to 100% of trees during 2002–06. In SREC plots, damage was minor and did not adversely affect appearance. Tree heights and growth rates varied significantly between seed sources. In general, corkbark fir grew faster than subalpine fir. After nine years in the field, mean heights of SREC-grown corkbark trees ranged from 2.1 to 2.9 m and that of subalpine trees ranged from 1.3 to 2.3 m, depending on seed source. Corkbark fir proved moderately resistant to resistant to a phoma-type fungal blight. Three corkbark seed sources appeared suitable for Christmas tree production. Subalpine trees were more susceptible to the blight. Some trees within both botanical varieties proved resistant to or highly tolerant of the blight, but the use of seedlings for landscapes may be unacceptably risky because of disease potential. Two fungicide programs (three applications of pyraclostrobin plus boscalid or one application of pyraclostrobin plus boscalid followed by one application of chlorothalonil) controlled the blight. Eight subalpine fir and 23 corkbark fir at SREC were selected for further testing as possible cultivars. Neither crop is recommended for sites with frequent or severe spring frosts.
Design, Construction, and Operation of a Demonstration Rainwater Harvesting System for Greenhouse Irrigation at McGill University, Canada
Authors: Islam Sadman , Lefsrud Mark , Adamowski Jan , Bissonnette Blake , Busgang Allison
Published: December 2018

Increasing stress on urban water demand has led to the exploration of the potential of rainwater use and water recycling to promote sustainable water resources management. Rainwater harvesting (RWH) not only has the potential to reduce water demand but also contributes to other sustainable objectives, including reducing stormwater pollutant loads, reducing erosion, and inducing natural flow regimes by means of flood control, in urban streams. This research involved the design, construction, and field-testing of an RWH system used to irrigate greenhouses at the Macdonald Campus of McGill University in Quebec, Canada. The purpose of the RWH system was to collect rainwater from a roof area of ≈610 m2 (the Horticulture Services Building on the Macdonald Campus of McGill University) to meet the irrigation demands of the two Horticulture Research Center greenhouses on the campus (≈149 m2 each) from May to October. Over its two years of operation, it was found that the amount of rainwater collected did not only meet the peak irrigation demands of the greenhouses (which amounted to almost 700 gal of water per day), but that there was also enough water for the irrigation of the nearby student-run gardens. The harvested rainwater was clear and did not cause any harm to the plants. The major problem that was experienced during the operation of the RWH system was that of algae growth in one of the water collection tanks. This issue was resolved by covering the tank with metallic green wallpaper, thereby blocking most of the sunlight from entering the tank. The RWH system is currently being used for irrigation and as a demonstration project to promote the learning of sustainable technologies on campus and in the surrounding communities.
Organic Leafy Greens Variety Trials in Kentucky: Identifying Superior Varieties for Small-scale Organic Farmers
Authors: Coolong Timothy , Law Derek M. , Snyder John C. , Rowell Brent , Williams Mark A.
Published: December 2018

Thirty-eight leafy greens, eight kale (Brassica oleracea acephala group), nine mustard (Brassica juncea), six arugula (Eruca sativa), five swiss chard (Beta vulgaris var. cicla), five collards (B. oleracea acephala group), and five turnip (Brassica rapa ssp. rapa) varieties were evaluated during Spring and Fall 2007–08 to determine suitability for organic production with respect to yield and stability. Trials were conducted on certified organic land using organic production practices. For mustard, kale, collards, and arugula, there were significant variety by season by year interactions. Despite these interactions, some varieties consistently performed well throughout the trial. ‘Florida Broadleaf’ was the highest yielding mustard in three of the four seasons evaluated. ‘Siberian’, ‘White Russian’, and ‘Red Russian’ were in the highest yielding group of kale varieties for overall yield. For collards, ‘Georgia/Southern’ and ‘Flash’ were part of the highest yielding group as determined by Duncan’s multiple range test in three of the four seasons examined. Turnip and swiss chard had significant year by variety interactions. Overall yields of ‘Alamo’ and ‘Alltop’, both F1 hybrids, were better than other turnip varieties assessed. Despite the interaction, ‘Fordhook Giant’ had superior yields in both years of the study. Arugula performance was significantly and negatively affected in Spring 2008. Overall, ‘Astro’, ‘Apollo’, and ‘Arugula’ had the greatest yields. This trial was designed to provide recommendations specifically for organic growers marketing directly to consumers.
Evaluation of Low-maintenance Landscape Roses in Central Florida
Authors: Mangandi Jozer , Brown Sydney Park , Peres Natalia
Published: December 2018

Environmental conditions in Florida are favorable for the development and persistence of insects and diseases that affect rose (Rosa sp.) plants, necessitating periodic applications of pesticides to maintain plant appearance. In addition, nutrient-deficient and well-drained soils in Florida force gardeners to provide supplemental fertilizer and water. Landscape performance is rarely considered for the development of new rose cultivars; consequently, careful selection of cultivars adapted to local conditions is necessary to reduce maintenance. The objective of this study was to develop recommendations of own-root, low-maintenance roses among 11 old garden and modern cultivars for central Florida. Plants were provided with minimal amounts of water and fertilizer, no control for diseases and insects, and no grooming or deadheading. Weekly evaluations were performed on all plants for plant quality, flower coverage; and incidence of black spot (caused by Diplocarpon rosae), cercospora leaf spot (caused by Cercospora rosicola), and foliar damage [caused by chilli thrips (Scirtothrips dorsalis)]. Damage caused by the foliar diseases and chilli thrips were the major factors that affected plant quality, vigor, and subsequently, flower production. Differences in susceptibility to these three factors were found among cultivars, enabling the classification of the 11 cultivars as recommended, cautiously recommended, and not recommended for central Florida. After two years, ‘Mrs. B.R. Cant’ appeared to be the most suited for central Florida as plant quality and flower production were fairly constant. ‘Duchesse de Brabant’, ‘RADrazz’ (Knock Out®), and ‘Spice’ were the next best performers and are cautiously recommended for central Florida. These cultivars were minimally affected by both diseases, showing low severity of yellowing and defoliation nor a decline in flower production. “Bailey Red”, ‘Old Blush’, ‘Belinda’s Dream’, ‘Perle d’Or’, ‘BUCbi’ (Carefree Beauty™), ‘Mutabilis’, and ‘WEKcisbako’ (Home Run®) had severe defoliation, poor growth, and low vigor in this study and do not appear to be low-maintenance landscape roses for central Florida.
Improving Bean Harvest with Gibberellic Acid
Authors: Pavlista Alexander D. , Hergert Gary , Santra Dipak K. , Schild James A.
Published: December 2018

The lowest pods on common bean (Phaseolus vulgaris) are on or near the ground. Yields may improve by raising these pods to reduce yield loss, especially with direct harvest. The objective of this field study was to use gibberellic acid (GA3) to raise lower pods and increase yield. Seeds of cultivars Poncho (Type III, pinto) and Matterhorn (Type II, great northern) were dipped in GA3 at 0, 125, 500, and 2000 ppm and planted in 30-inch rows (2005). Stem elongation was promoted, but emergence and yield were decreased especially for ‘Poncho’. In foliar tests in 30-inch rows (2005 and 2006), GA3 was applied to newly expanded unifoliolate leaves. Doses were 0, 0.5, 2, and 8 ppm for ‘Poncho’ and 0, 31.25, 125, and 500 ppm for ‘Matterhorn’. The higher doses raised the low pod by 2 inches, and yields harvested conventionally were increased from 14% to 18%. In 2007, ‘Poncho’ and ‘Matterhorn’ unifoliolate leaves were treated with GA3 at 0, 2, and 4 ppm, and 0, 62.5, and 125 ppm, respectively, and then portions of each plot were harvested either manually, conventionally, or directly. Planting was in 22- and 30-inch row spacing. Lower pods were raised by ≈1 inch by GA3. Yields from conventional and direct harvest were increased by foliar GA3 application for both cultivars and both row spacings. Yield from directly harvested GA3-treated plots was comparable to that from untreated conventionally harvested plots. GA3 may play a role in increasing yield from directly harvested common bean in conjunction with genetic and mechanical improvements.
Evaluation of Container Ornamental Species Tolerance to Three p-hydroxyphenylpyruvate Dioxygenase-inhibiting Herbicides
Authors: Cutulle Matthew A. , Armel Gregory R. , Brosnan James T. , Kopsell Dean A. , Klingeman William E. , Flanagan Phillip C. , Breeden Gregory K. , Vargas Jose J. , Koepke-Hill Rebecca , Halcomb Mark A.
Published: December 2018

Selective weed control in ornamental plant production can be difficult as many herbicides can cause unacceptable injury. Research was conducted to evaluate the tolerance of several ornamental species to applications of p-hydroxyphenylpyruvate dioxygenase (HPPD)-inhibiting herbicides for the control of problematic weeds in ornamental production. Mestotrione (0.09, 0.18, and 0.36 lb/acre), tembotrione (0.08, 0.16, and 0.32 lb/acre), and topramezone (0.016, 0.032, and 0.064 lb/acre) were applied alone postemergence (POST) in comparison with the photosystem II-inhibiting herbicide, bentazon (0.5 lb/acre). All herbicide treatments, with the exception of the two highest rates of tembotrione, caused less than 8% injury to ‘Noble Upright’ japanese holly (Ilex crenata) and ‘Compactus’ burning bush (Euonymus alatus). Similarly, no herbicide treatment caused greater than 12% injury to ‘Girard’s Rose’ azalea (Azalea). Conversely, all herbicides injured flowering dogwood (Cornus florida) 10% to 23%. Mesotrione- and tembotrione-injured ‘Radrazz’ rose (Rosa) 18% to 55%, compared with only 5% to 18% with topramezone. ‘Siloam June Bug’ daylily (Hemerocallis) injury with topramezone and tembotrione was less than 10%. Topramezone was the only herbicide evaluated that provided at least 93% control of redroot pigweed (Amaranthus retroflexus) with all application rates by 4 weeks after treatment (WAT). Redroot pigweed was controlled 67% to 100% with mesotrione and tembotrione by 4 WAT, but this activity was variable among application rates. Spotted spurge (Chamaesyce maculata) was only adequately controlled by mesotrione applications at 0.18 and 0.36 lb/acre, whereas chamberbitter (Phyllanthus urinaria) was not controlled sufficiently with any herbicide evaluated in these studies. Yellow nutsedge (Cyperus esculentus) was suppressed 72% to 87% with mesotrione applications at 0.18 lb/acre or higher and with bentazon at 0.5 lb/acre by 4 WAT. All other herbicide treatments provided less than 58% control of yellow nutsedge. In the second study, ‘Patriot’ hosta (Hosta), ‘Green Sheen’ pachysandra (Pachysandra terminalis), autumn fern (Dryopteris erythrosora), ‘Little Princess’ spirea (Spiraea japonica), ‘Green Giant’ arborvitae (Thuja plicata), and ‘Rosea’ weigela (Weigela florida) displayed no response to topramezone when applied at 0.024 and 0.095 lb/acre. Since 10 ornamental species in our studies exhibited less than 10% herbicidal response with all rates of at least one HPPD-inhibiting herbicide then it is possible that these herbicides may provide selective POST weed control in ornamental production systems.
Establishment of Perennial Ryegrass in Soil with Simulated Petroleum-based Spills and Remediation
Authors: Bai Ruiqin , Li Deying
Published: December 2018

Petroleum-based spills on turfgrass often occur during lawn care maintenance. The damages caused by hydrocarbons to turfgrass can be long lasting and difficult to correct because of the stable and toxic nature of hydrocarbons. The objective of this study was to compare the effectiveness of using detergent, nitrate nutrient, humic substance, and activated charcoal to enhance bioremediation and turf recover after gasoline, diesel, and hydraulic fluid spills. The turfgrass quality and reestablishment of perennial ryegrass (Lolium perenne) reseeded at 0, 1, and 2 weeks after spills were evaluated. The results showed that using a liquid humic substance to remediate soil and reseed immediately after a gasoline spill was a practical method to reestablish acceptable turfgrass quality in 5 weeks. The most significant injury to perennial ryegrass caused by gasoline was bleaching of green tissues. Gasoline caused negligible residual herbicidal effects under the remediation regime in this study. However, diesel or hydraulic fluid showed phytotoxicity and residual effects in the contaminated soil for more than 2 months. Seeds applied immediately after diesel and hydraulic fluid spills lost viability as a result of the herbicidal effect of these hydrocarbons. As a result, reseeding was only successful 4 months after diesel and hydraulic fluid spills. Therefore, the time span for reestablishing perennial ryegrass turf may be too long for practical purposes in the lawn care industry.
Experiential Learning through Partnership: A Case Study of a Collaborative, Hands-on Program to Teach High School Students Organic Farming
Authors: Silva Erin M. , Muller Geraldine
Published: December 2018

In 2008, a collaborative project was initiated between the La Farge School District (La Farge, WI), University of Wisconsin–Madison College of Agriculture and Life Sciences, Organic Valley Cooperative Regions Organic Producers Pools (La Farge, WI), and Kickapoo Valley Reserve (La Farge, WI). The overarching mission of the program is to build a sustainable, hands-on educational farm and corresponding curriculum to teach organic agriculture principles to high school students and increase the number of students entering agriculture-related professional fields. Secondary goals of the project include delivering locally grown organic produce and related organic agriculture educational opportunities to the broader community. To achieve these goals, a multifaceted student internship program was created that includes a range of experiential learning opportunities for students. With the participation of each of the project partners, about ten students per year engage in the field production of certified organic vegetables, participate in field trips to sites related to organic agriculture, and distribute the produce to the school and the broader community. Through the integration of these activities, students are taught key principles of successful organic management, including ecologically based disease, weed, and insect management, development of a soil fertility plan, market analysis and its implications of crop selection, and determination of costs of production. In the face of both successes and challenges, through informal evaluation of students and the project team, the program continues to develop each year.
Are There Horticulture-related Mobile Applications for Me?
Authors: Kobayashi Kent D.
Published: December 2018

Mobile devices such as smartphones and tablet computers are increasingly being used to supplement the use of laptops and desktop computers. Their small size makes them portable and convenient to use. These devices are providing horticulturists with new tools for their work. Mobile applications (apps) are software applications that run on smartphones and tablet computers. They can be easily downloaded to a smartphone or tablet computer. There are hundreds of thousands of apps available, covering a wide range of topics. Many apps are free, whereas others have a cost. Horticulture-related apps for research, extension, teaching, and industry are available. These apps deal with diverse topics such as food safety, geographic information systems, hydroponics, scouting for insects, turfgrass management and weeds, plant growth regulator (PGR) calculations, conservation trees (trees suitable and recommended for conservation plantings), landscape design, plant and tree identification, crop protection product information, and industry trade publications. This article gives an overview of some of the horticulture-related apps that are available. Are there horticulture-related mobile apps for me? Yes!
Developing a Mobile Application as an Extension Education Tool: A Case Study Using IPMPro
Authors: Fulcher Amy , Chong Juang-Horng (JC) , White Sarah A. , Neal Joseph C. , Williams-Woodward Jean L. , Adkins Craig R. , Braman S. Kristine , Chappell Matthew R. , Derr Jeffrey F. , Dunwell Winston C. , Frank Steven D. , Gill Stanton A. , Hale Frank A. , Klingeman William E. , LeBude Anthony V. , Rane Karen , Windham Alan S.
Published: December 2018

With increased mobile device usage, mobile applications (apps) are emerging as an extension medium, well suited to “place-less” knowledge transfer. Conceptualizing, designing, and developing an app can be a daunting process. This article summarizes the considerations and steps that must be taken to successfully develop an app and is based on the authors’ experience developing two horticulture apps, IPMPro and IPMLite. These apps provide information for major pests and plant care tasks and prompt users to take action on time-sensitive tasks with push notifications scheduled specifically for their location. Topics such as selecting between a web app and a native app, choosing the platform(s) for native apps, and designing the user interface are covered. Whether to charge to download the app or have free access, and navigating the intra- and interinstitutional agreements and programming contract are also discussed. Lastly, the nonprogramming costs such as creating, editing, and uploading content, as well as ongoing app management and updates are discussed.
A Method to Quantitatively Classify Residential Urban Landscapes in a Desert Environment
Authors: Al-Ajlouni Malik G. , VanLeeuwen Dawn M. , DeMers Michael N. , St. Hilaire Rolston
Published: December 2018

The apparent heterogeneity of human-generated materials in residential urban landscapes sustains concerns that the quantitative classification of urban residential landscapes is impossible. The objective of this research was to develop a method to quantitatively classify urban residential landscapes in a desert environment. Using a purposive sampling procedure, we studied the landscapable area around each of 54 residential homes in Las Cruces, NM. All materials in the landscape were identified, measured, and categorized. Using 30% as the cutoff to indicate that a material was dominant in the landscape, we classified 93% of all landscapes into nine common landscape types. Mulch-dominant landscapes were the most common, and landscape types differed between front- and backyards. Shrubs did not feature prominently in any of the common landscape types. Our classification method clearly identifies multiple landscape types, and for the first time, provides quantitative evidence that landscape types are distributed differently in front- and backyard landscapes in the desert environment of Las Cruces. Information on common landscape types will be valuable to landscape horticulturists wanting to craft water conservation plans that are landscape specific if the common landscape type can be linked to a landscape water budget.
Practical Field Use of Eye-tracking Devices for Consumer Research in the Retail Environment
Authors: Behe Bridget K. , Fernandez R. Thomas , Huddleston Patricia T. , Minahan Stella , Getter Kristin L. , Sage Lynnell , Jones Allison M.
Published: December 2018

Eye-tracking equipment is now affordable and portable, making it a practical instrument for consumer research. Engineered to best analyze gaze on a plane (e.g., a retail shelf), both portable eye-tracking glasses and computer monitor–mounted hardware can play key roles in analyzing merchandise displays to better understand what consumers view. Researchers and practitioners can use that information to improve the sales efficacy of displays. Eye-tracking hardware was nearly exclusively used to investigate the reading process but can now be used for a broader range of study, namely in retail settings. This article presents an approach to using glasses eye tracker (GET) and light eye tracker (LET) eye-tracking hardware for applied consumer research in the field. We outline equipment use, study construction, data extraction as well as benefits and limitations of the technology collected from several pilot studies.
Evaluation of Variation in Time of Harvest Maturity of Flowering Shoots in Three Cultivars of Gentian
Authors: Samarakoon Uttara C. , Funnell Keith A. , Woolley David J. , Morgan Edward R.
Published: December 2018

The time to harvest maturity of flowering shoots and the extent and source of variability in maturity dates differed among cultivars of gentian (Gentiana sp.), with a wider spread in time to harvest maturity in Showtime Starlet (41 days) than Showtime Diva (35 days) and Showtime Spotlight (29 days). Cultivars also differed by more than twice in their plant-to-plant variability in time to harvest. Although later-emerging shoots reached harvest maturity more quickly than earlier-emerging shoots, the use of growing degree-days (GDD) for this field-grown cut flower did not account for differences. For ‘Showtime Diva’, 77% of outliers reached harvest maturity at the beginning of the season (i.e., before the 10th percentile). For ‘Showtime Spotlight’, only 20% of shoots classified as outliers flowered early with the remaining 80% emerging late (i.e., after the 90th percentile). Strategies to control the spread in time to harvest maturity in late-maturing cultivars such as Showtime Starlet should focus on uniform shoot emergence and controlling temperature during growth. Although strategies to achieve uniform shoot emergence should also be targeted for ‘Showtime Diva’, controlling temperature during the growing season would not appear to offer significant control of the spread in time of harvesting floral shoots. However, in earlier-maturing cultivars such as Showtime Spotlight, strategies will primarily require a greater understanding of the factors influencing the variability in maturation of shoots within individual plants before, and after, emergence.
Academic, Internship, and Cooperative Extension Programs at Botanic Gardens
Authors: Meyer Mary Hockenberry , Michener David
Published: December 2018

Fifty-five online survey responses, 15 phone interviews, and 9 site visits were conducted to collect information on academic (for credit) classes, internships, and Cooperative Extension programs at botanic gardens and arboreta in the United States. Academic programs investigated were primarily instructional credit classes. Thirty-five (64%) of the respondents indicated their garden offers an entire or partial academic class on-site. The most limiting factor in offering more academic classes was faculty time or staff limitations, as indicated by 21 participants (38%). Thirty-one (56%) gardens offer some type of internship, although only 16 (30%) were offering an academic (for credit) internship. Respondents indicated extension involvement as follows: Extension Specialists/Extension Master Gardeners (EMG) teach classes on-site, 23 (42%); EMG training was held on-site, 17 (31%); EMG answered questions on-site, 16 (29%); and 26 (47%) indicated “other” extension collaboration. Sixty-six percent reported their working relationship with extension as minimal or fair as opposed to 33% who described their extension relationship as good to excellent. Examples of successful programs in these three areas are presented, which offer models for collaborative work between botanic gardens, academia, and extension.
Exploring the Effects of Extension Workshops on Household Water-use Behavior
Authors: Borisova Tatiana , Useche Pilar
Published: December 2018

The effectiveness of 2-hour extension workshops focused on residential water conservation is examined. We used a sample of irrigation water-use data for 57 workshop participants and 43 nonparticipants, and applied a fixed effect regression analysis method. The results show that the workshops were effective in reducing attendees’ irrigation water use; however, the effect was short-lived. Furthermore, the effect of the workshop attendance depended on the household sample considered, and for a subsample of low-use workshop participants, water use tended to increase following the workshop.
Costs and Benefits of Implementing Sensor-controlled Irrigation in a Commercial Pot-in-Pot Container Nursery
Authors: Belayneh Bruk E. , Lea-Cox John D. , Lichtenberg Erik
Published: December 2018

Irrigation scheduling in ornamental plant production is complex due to the large number of species grown by individual growers and the need to consider plant, environment, and substrate conditions to make correct irrigation decisions on a daily or more frequent basis. The engineering team in our project has developed a smart wireless sensor node that is capable of integrating outputs from a range of soil moisture and environmental sensors to schedule irrigation events. In addition, an advanced monitoring and control software enables growers to manage irrigation based on set-point or model-based protocols, which are then independently executed by the nodes, enhancing or replacing human decision making. During 2012, we implemented a sensor-controlled vs. grower-controlled irrigation study at a pot-in-pot nursery in Tennessee. Sensor networks were installed in two separate production blocks of 3-year-old dogwood (Cornus florida ‘Cherokee Brave’) and 2-year-old red maple (Acer rubrum ‘Autumn Blaze’) trees grown in 15- and 30-gal containers, respectively. One row of trees in each block was irrigated based on the average reading of soil moisture sensors inserted in individual trees using micropulse irrigation, i.e., sensor controlled. Trees in the adjacent row and the rest of the block were independently irrigated by the grower using standard practices, i.e., grower controlled. Sensor volumetric water content (VWC) readings and irrigation volumes were logged by nodes on a 15-min basis and were relayed to a base station on the farm. For the study period between Mar. 2012 and Nov. 2012, average daily water applied by the grower-controlled irrigation to the dogwood block was 0.92 gal/tree, compared with 0.34 gal/tree applied using sensor-controlled irrigation; for red maple, these values were 1.72 gal/tree and 1.13 gal/tree, respectively. No significant differences in tree caliper or quality were noted between the two irrigation treatments in either species over the year. The cost of water for this particular operation was negligible consisting only of pumping costs, as water is drawn from a perennial stream with excellent water quality. Consequently, a conservative return on investment for a wireless sensor network capable of covering the entire operation was 37.5%, corresponding to a payback period of 2.7 years, associated almost entirely from a reduction in irrigation management time. Pricing in a nominal cost for water of $326 per acre-foot ($1 per 1000 gal) increased annualized net savings 9-fold, reducing the payback period to less than 4 months. This analysis did not factor in additional economic benefits such as reductions in production time, losses due to disease, or increased plant quality, which have been associated with the use of sensor-based irrigation control in other studies.
Optimizing Irrigation of Fresh Market Tomato Grown in the Mid-Atlantic United States
Authors: Fleming Catherine S. , Reiter Mark S. , Freeman Joshua H. , Maguire Rory
Published: December 2018

Determining irrigation requirements for fresh market tomato (Solanum lycopersicum) production is essential to obtain optimum yields, cost-effective water use, and minimize nitrate leaching. The objective of this study was to determine the appropriate irrigation rate for polyethylene-mulched fresh market tomato grown in Virginia. This study investigated irrigation regimes by applying water based on evapotranspiration (ET) calculations in three spring and three fall seasons. Plants were grown using 0.0 × ET, 0.5 × ET, 1.0 × ET, 1.5 × ET, and 2.0 × ET. Additional irrigation treatments involved tensiometers installed at 12-inch depth in the bed, programmed to irrigate at soil moisture set points of −20, −40, and −60 kPa. Tensiometer treatments were able to irrigate up to nine times per day if soil moisture fell below the designated moisture set point. Measurements included fruit yield, plant and fruit nitrogen (N) uptake, and inorganic soil nitrate-N (NO3-N) at 0 to 10-, 10 to 20-, and 20 to 30-inch depths. Overall, the 0.5 × ET treatment provided optimum yields in all growing seasons except Spring 2010, which was unseasonably hot and dry. A tensiometer treatment (−40 kPa) provided optimum yields in all growing seasons, and was able to adjust irrigation in a hot and dry season. Residual soil NO3-N at 0 to 10 inches generally exhibited an inverse relationship with yield; greater yields resulted in less residual soil NO3-N. In most treatments throughout the duration of this study, plant N uptake + fruit N uptake accounted for most of the N fertilizer applied (68% to 151%). In conclusion, an irrigation rate of 0.5 × ET and a tensiometer treatment (−40 kPa) provided minimal irrigation inputs to obtain optimum marketable yields while also minimizing residual soil nitrate that may be prone to leaching after the season.