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Matthew D. Kleinhenz, Sonia Walker, John Cardina, Marvin Batte, Parwinder Grewal, Brian McSpadden-Gardener, Sally Miller, and Deborah Stinner

The risk: reward for a transition to organic vegetable farming near urban areas and changes in soil, crop, and economic parameters during transition are poorly understood. A 4-year study was initiated in 2003 at the Ohio State Univ.–OARDC to document the relative advantages of four transition strategies and their effects on major cropping system variables. Soil previously in a vegetable-agronomic crop rotation has been maintained fallow, planted to a mixed-species hay, used in open field vegetable production, or used in vegetable production under high tunnels, transition strategies with a range of management intensity and expected financial return. Each strategy was replicated four times within the overall experimental area. Half of the soil in each strategy unit was amended with composted dairy manure while the remaining soil was unamended. Field vegetable plots have been planted to potato, butternut squash, and green bean. High tunnels have been planted to potato, zucchini, and a fall–spring rotation of beet, swiss chard, mixed lettuce, radish, and spinach. Data describing the outcomes of the strategies in terms of farm economics, crop yield and quality, weed ecology, plant pest and disease levels, and soil characteristics (physical, chemical, biological) have been recorded. Inputs in the high tunnels have exceeded inputs in all other strategies; however, high tunnel production has widened planting and harvesting windows and increased potato yield, relative to open field production. To date, compost application has increased crop yield 30% to 230% and influenced crop quality, based on analytical and human panelist measures. Weed (emerged seedlings, seedbank) and nematode populations also continue to vary among the transition strategies.

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Lee F. Johnson, Michael Cahn, Frank Martin, Forrest Melton, Sharon Benzen, Barry Farrara, and Kirk Post

Estimation of crop evapotranspiration supports efficient irrigation water management, which in turn supports water conservation, mitigation of groundwater depletion/degradation, energy savings, and crop quality maintenance. Past research in California has revealed strong relationships between fraction of the ground covered by photosynthetically active vegetation (Fc), crop coefficients (Kc), and evapotranspiration (ET) of cool-season vegetables and other specialty crops. Replicated irrigation trials for iceberg lettuce and broccoli were performed during 2012 and 2013 at the USDA Agricultural Research Station in Salinas, CA. The main objective was to compare crop yield and quality from ET-based irrigation scheduling with industry standard practice. Sprinkler irrigation was used to germinate and establish the crops, followed by surface drip irrigation during the treatment period. Each experiment compared three irrigation treatment schedules replicated five times in a randomized block design. Two decision-support models were evaluated as follows: 1) an FAO-56-based algorithm embedded in NASA’s prototype Satellite Information Management System (SIMS) based on observed Fc, and 2) CropManage (CM), an online database-driven irrigation scheduling tool based on modeled Fc. Both methods used daily reference ETo data from the California Irrigation Management Irrigation System (CIMIS) to translate Kc to crop ET, with a target of 100% replacement of water use during the drip irrigation phase. A third treatment followed an irrigation schedule representing grower standard practice (SP) at 150% to 175% ET replacement during the drip irrigation phase. No significant treatment differences were seen in lettuce head weight or total biomass. Marketable yields of lettuce (near 45.4 Mg·ha−1) and broccoli (near 17.4 Mg·ha−1) were in-line with industry averages during both years and all treatments. During 2012, CM yield was below lettuce SP, and above broccoli SP, while in 2013 no treatment differences were detected for either crop. No significant differences were detected between SIMS and SP yields during any trial.

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Albert N. Kishaba, Steven J. Castle, Donald L. Coudriet, James D. McCreight, and G. Weston Bohn

yellow mosaic virus. 1 Research Entomologist. Present address: Crop Quality and Fruit Insects Research, 2301 S. International Blvd., Weslaco, TX 78596. 2 Present address: SW Idaho Research and Extension Center, 29603 U of I Lane, Parma ID 83660-9637. 3

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William K. Harris, Joyce G. Latimer, John F. Freeborn, Margaret Aiken, and Holly L. Scoggins

Despite the popularity of fountain grass (Pennisetum alopecuroides) as a landscape perennial, little research has been conducted on nursery management practices that maximize its overwintering survival and subsequent spring vigor in container production systems. An experiment was conducted to determine the effect of protective covers (a double layer of insulation fabric, a double layer of insulation fabric plus a single sheet of white polyethylene plastic, or no cover), fertilizer application rate (high and low), and substrate moisture content (irrigated when substrate volumetric water content (VWC) fell below 15% and 25%) on the survival rate and vigor of container-grown fountain grass: straight species fountain grass (SFG), ‘Hameln’ fountain grass (HFG), and ‘Little Bunny’ fountain grass (LBFG). Plants were overwintered in a coldframe and were evaluated for survival rate (percent that survived the winter) and vigor (visual rating scale 1 to 5) the following spring. Survival rate and vigor ratings varied among species. However, the highest survival rates (generally 75% or greater) and vigor ratings (generally 3 or greater) were in treatments that used protective covers, though there was not a clear advantage to using white polyethylene in addition to the double layer of insulation fabric. In treatments that used either of the protective covering methods and the high fertilizer application rate, 25% or less of LBFG survived and had vigor ratings of 1.3 or less. In contrast, 75% of LBFG survived when the low fertilizer rate was used in conjunction with either protective covering method. Substrate moisture content only affected the survival rates of SFG and HFG when no protective cover was used, although these survival rates were less than those with covers. These results suggest that protective covers may serve as a tool to minimize winter damage and improve crop quality for the species used in this trial. Because of the varied capacity among these cultivars to tolerate different fertilizer rates and substrate moisture contents, it is recommended that growers use the results of this study as a baseline for conducting site evaluations to determine overwintering techniques that maximize survival and vigor on their facilities.

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Rebecca J. Long, Rebecca N. Brown, and José A. Amador

Using organic wastes as agricultural amendments is a productive alternative to disposal in landfills, providing nutrients for plant growth and carbon to build soil organic matter. Despite these benefits, a large fraction of organic waste is sent to landfills. Obstacles to the adoption of wastes as sources of plant nutrients include questions about harmful effects to crops or soils and the wastes’ ability to produce satisfactory yields. We compared six organic waste amendments with a mineral fertilizer control (CN) to determine effects on soil quality, soil fertility, crop quality, and crop yield in 2013 and 2014. Waste amendments were applied at a rate sufficient to supply 10,000 kg organic C/ha over two seasons, and mineral fertilizer was applied to control plots to provide 112 kg-N/ha/yr. The experiment was laid out in a randomized block design with four replicates and three crops: sweet corn (Zea mays L. cv. Applause, Brocade, and Montauk), butternut squash (Cucurbita moschata Duchesne cv. JWS 6823), and potatoes (Solanum tuberosum L. cv. Eva). Amendment with biosolids/yard waste cocompost (BS), dehydrated restaurant food waste (FW), gelatin manufacturing waste (GW), multisource compost (MS), paper fiber/chicken manure blend (PF), and yard waste compost (YW) did not have a negative impact on soil moisture, bulk density, electrical conductivity (EC), or the concentration of heavy metals in soil or plant tissue. Our results indicate potential uses for waste amendments including significantly raising soil pH (MS) and increasing soil organic matter [OM (YW and BS)]. The carbon-to-nitrogen ratio (C:N) of waste amendments was not a reliable predictor of soil inorganic N levels, and only some wastes increased potentially mineralizable nitrogen (PMN) levels relative to the control. Plots amended with BS, FW, and GW produced yields of sweet corn, butternut squash, and potatoes comparable with the control, whereas plots amended with YW, PF, and MS produced lower yields of sweet corn, squash, or both, although yields for potatoes were comparable with the control. In addition, the marketability of potatoes from PF plots was significantly better than that of the control in 2014. None of the wastes evaluated in this study had negative impacts on soil properties, some provided benefits to soil quality, and all produced comparable yields for at least one crop. Our results suggest that all six wastes have potential to be used as sources of plant nutrients.

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Sally M. Schneider and Bradley D. Hanson

Nursery producers of perennial fruit and nut plants rely on preplant fumigation to meet regulatory requirements designed to ensure nematode-free planting stock. In the past, preplant treatments with methyl bromide or high rates of 1,3-dichloropropene were the preferred treatments. However, the phase out of methyl bromide due to environmental concerns and evolving regulations on the use of 1,3-dichloropropene has increased the need for effective and economical alternative fumigation treatments in open field nursery production. A field trial was conducted in a commercial nursery to test weed and nematode control with several tarped and untarped preplant applications of 1,3-dichloropropene, chloropicrin, and iodomethane in comparison with methyl bromide. Crop safety and nematode infestation were evaluated on a wide range of tree, vine, and berry nursery stock. No fall fumigation treatment in this study resulted in measurable injury to spring-planted nursery stock. There were few statistical differences between methyl bromide and the other fumigation treatments in crop establishment, crop quality, or nematode level at planting 5 months after treatment, although some untarped treatments had detectable levels of the root-knot nematode (Meloidogyne spp.). At grape (Vitus vinifera) and bramble (Rubus spp.) harvest after the first growing season, few statistical differences were noted in the number of nematodes isolated from roots; however, only methyl bromide had nondetectable levels in all varieties. The highest nematode levels were usually found in untarped iodomethane:chloropicrin and untarped chloropicrin plots. At tree harvest 26 months after fumigation, root-knot nematodes were isolated from the roots of highly susceptible tree varieties in several iodomethane:chloropicrin treatments and in chloropicrin alone plots. Untarped applications did not provide commercially acceptable control of weeds or root-knot nematode in this trial. Tarped applications of 30:70 and 50:50 iodomethane:chloropicrin provided nematode control similar to 1,3-dichloropropene, although not as good as methyl bromide. Iodomethane:chloropicrin combinations have been registered in other states and should be considered for use in California perennial fruit and nut crop nurseries as an alternative to methyl bromide.

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of the Illinois Budding Plant and Pot Plant Schools. Professor Carbonneau was a highly respected coach of the Collegiate Floral Crop Quality and Evaluation Competition sponsored by Pi Alpha Xi. He was a member and adviser to several professional and

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Charles Benbrook

been remarkably successful in pushing these plateaus higher, it has not eliminated them and likely never will for the vast majority of food. Accordingly, we cannot maximize both yields and crop quality when quality is defined in terms of nutrient

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Ryan M. Warner

photoperiod for floral induction; 2) the minimum number of short-day cycles necessary for floral induction; and 3) the impact of early flowering on phenotypic characteristics associated with crop quality. Materials and Methods Expt. 1: Photoperiod treatments

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Fumiomi Takeda and Penelope Perkins-Veazie

season, and improving crop quality and yield. Also, rainfall protection provided by plastic covering decreases incidence of foliar and fruit diseases. The increased elevation in air and soil temperatures and diffused lighting realized in high tunnels in