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Abstract
A net present value analysis was conducted for the conversion from the Umbrella Kniffin training system to the Geneva Double Curtain training system for growing ‘Concord’ grapes (Vitis labruscana Bailey) in New York. The optimal cultural considerations included no overcropping and following a trunk renewal plan. For the optimal plan, conversion to the Geneva Double Curtain system was found to be a profitable investment alternative.
Forty eight California sycamores (Platanus racemosa) were planted (5/91) from one gallon containers and mulched (8/91) with, pine bark, composted sewage sludge and wood products, fresh Eucalyptus cladocalyx chips (large 2-6cm), fresh eucalyptus chips (small <1cm), composted large eucalyptus and untreated. Mulches were applied to a depth of 10cm in a 6m2 area around each tree. Irrigations were based on soil moisture depletion and water content was measured by time domain reflectometry. Mulched trees developed more caliper, lower stomatal resistances and lower trunk temperatures. Soil moisture (top 15cm) was greater under mulched trees. Rooting was evident in the sludge, and composted eucalyptus mulches but absent in the pine bark and fresh eucalyptus mulches.
Nursery and greenhouse growers have an important role to play in conserving water resources. Many technologies are available to help growers conserve water. Yet, within the industry, there may be varying levels of knowledge about a specific strategy, along with inconsistent adoption and continued use. An understanding of these factors can be incorporated into educational programming for this audience. This study evaluated the reported knowledge level of U.S. greenhouse and nursery growers about eight specific water conservation technologies and then explored the rate at which growers had adopted and continued or discontinued their use. Technologies were ranked from high to low adoption rate, beginning with drip irrigation, rainwater capture, water reuse, and microirrigation, followed by soil moisture sensors, climate-based irrigation, subirrigation, and finally an irrigation audit. Overall, greater levels of knowledge corresponded to both greater adoption and continued use of a technology. Other factors, such as economic cost and technical feasibility are undoubtedly important. Findings highlight an opportunity to focus educational programs on the systems-based strategies that are beneficial to growers, but growers are least knowledgeable about to increase adoption of effective water conservation methods that currently have low levels of grower implementation.
Abstract
Root lengths of an adventitious root system (creeping bentgrass, Agrostis palustris Huds.) and a woody plant fiberous root system (Hetz juniper, Juniperus chinensis L. ‘Hetzii’) were estimated using an automated method employing a video camera and an area/length meter to count scanning line and root intersections. A grid method of root length estimation was used for comparison. Under- and overestimation was random when the automated method was used for creeping bentgrass samples (<80 cm) and the shorter group of juniper root samples (150-550 cm). However, these estimates were much closer to the actual root length, in the ranges evaluated, than the estimates from the grid method. The lengths of long juniper root samples (600-3000 cm) were underestimated consistently with the automated method. The magnitude of this underestimation increased with increasing length. However, the relationship between estimated and actual root length remained linear and was about 76% of the actual length. For the ranges of root length evaluated, this method was found to be useful for root length estimation.
Urban landscape irrigation is becoming increasingly important from a resource management point of view. Significant water use savings may be achieved if landscape irrigation is based on reference evapotranspiration (ETo). This study measured landscape crop coefficients (KL) for landscapes that are comprised of different vegetation types and irrigation water quality differences affecting KL. The KL was determined from the ratio of actual evapotranspiration to the ETo calculated from the modified Penman-Monteith equation. Irrigation quantity was based on 100% replacement of ETo. The KL values were determined for the following landscape vegetation on a fine sandy loam: St. Augustinegrass [Stenotaphrum secundatum (Walt.) Kuntze.], a single shumard red oak (Quercus shumardii Buckl.), St. Augustinegrass plus red oak, native grasses [Muhlenbergia capillaries (Lam.) Trin. and Schizachyrium scoparium (Michx.) Nash], and native grasses plus Red Oak in both College Station (CS) and San Antonio (SA), TX. Soil was systematically placed into lysimeters containing a drainage system and soil moisture probes. Lysimeters (1136 L) were placed in-ground in a randomized complete block design with three blocks. Soil moisture measurements were made at 0- to 20-, 20- to 40-, and 40- to 60-cm depths. The KL was determined after a rainfall or irrigation event for periods of 2 to 5 days. During the combined growing seasons of 2007 and 2008, KL in SA increased from early, to mid, to late season. In CS, the KL was unaffected by plant treatment or season. The St. Augustinegrass treatment KL seasonally ranged from 0.45 to 0.62 in SA. In CS, soil sodium accumulation caused decreased KL. These results of KL for mixed-species landscapes on non-sodic sites trend toward seasonal values of 0.5 to 0.7 for irrigation decisions in southern Texas. Landscape coefficients can be used as a tool in irrigation decision-making, which could contribute to water savings in amenity landscapes.
Effective landscape management practices in urban landscapes must include an awareness of nutrient removal from soil caused by leaching, and these practices should be those least damaging to freshwaters. Annual mean dissolved organic carbon (DOC), dissolved organic nitrogen (DON), nitrate-N, ammonium-N, soluble phosphate, and bicarbonate concentrations and fluxes were quantified in leachate from landscapes planted with different urban horticultural types. Plot vegetation consisted of either a single species or mixed species. The experiment was conducted at two sites in Texas with significantly different irrigation water chemistry. At the two sites, plant species had a significant effect on PO4 3--P flux, and irrigation chemistry had a significant effect on all nutrient fluxes. There was an interaction between plant species and irrigation chemistry for PO4 3--P flux (P < 0.05) only. The relationship between bicarbonate and DOC flux at sites was stronger and significant (0.92; P < 0.05) at the site irrigated with Na-HCO3 municipal tap water than at the site irrigated with Ca-HCO3 municipal tap water (R 2 = 0.76, P = 0.05). Type of irrigation water chemistry may result in lower plant water uptake resulting in increased nutrients lost to leachate.
There are many water treatment technologies available to the nursery and greenhouse industry, but this sector has been somewhat hesitant to adopt them. An online survey was used to evaluate nursery and greenhouse growers’ knowledge, implementation, and continued use of 12 water treatment technologies. Less than 24% of the growers had used a water treatment technology. The knowledge level was low overall, and fewer than one in four growers had implemented all 12 technologies. However, most growers who had implemented 10 of the 12 technologies continued to use them. The results imply water treatment technologies available for this group are somewhat unknown and underused, thereby implying that there is a need to increase awareness of these innovations and highlight the opportunity for growers to advocate for treatment technology use among their peers.
In 2014, the Southern Nursery Integrated Pest Management (SNIPM) Working Group published both print and electronic versions of IPM for Shrubs in Southeastern U.S. Nursery Production: Volume I. Five hundred print books (of 3000 copies) were distributed to commercial ornamental growers and extension educators in return for their participation in a follow-up survey. The survey was administered to determine the value of book contents, savings that growers realized from using the book, perceived value of the book had users been asked to pay for it, and demographic information. The survey response rate was 46.2%, with respondents from 18 states. Of 243 respondents, 194 (79.8%) had used the book. Entomology information was most used and most useful, followed by plant pathology, weed science, and cultural information. Collective savings attributed to book use totaled $408,832/year for the 194 nurseries that used the book. Applying the use rate (79.8%) identified in this survey, this represents $5.62 million in savings per year for the 3000 printed books, of which 2394 are estimated to have been used. Savings varied by the type and size of operation. Larger operations had greater savings per year. Container growers saved $44.15/acre and field growers $28.37/acre. The price that growers were willing to pay for the book also varied by operation type and size. Extension educators and growers were willing to pay an average of $41.20, with an additional $0.063/acre for container growers and $0.126/acre for field growers. Return on investment for the U.S. Department of Agriculture grant funding for the project was $187.60 per dollar of funding. This survey demonstrates that collaborative efforts can produce high-value deliverables with significant regional and/or national impact.
Potato (Solanum tuberosum) is a high value crop in Florida. It consistently ranks in the top five valued vegetable crops produced in the state. The identification of new potato varieties that improve production efficiency is an imperative because of constantly evolving market and production demands. A chip potato variety evaluation experiment was conducted in northeast Florida in 2002 to compare the production characteristics of industry standards to advanced selections. The potato varieties evaluated in this experiment were bred specifically for processing by the potato chip industry. The experimental design was a four (site) by five (variety) factorial with four replications at each site. The sites were the University of Florida's research farm in Hastings, FL and three commercial farms in the surrounding area. Potato varieties were two seed sources of `Atlantic', as well as, `Snowden', B0564-8, and B0766-3. Marketable yield for each variety was 39.4, 33.4, 38.4, 33.6, and 33.6 t·ha-1 (351, 298, 343, 300, and 300 cwt/acre), respectively. Total yield of B0564-8 was statistically equivalent to an `Atlantic' standard at all four locations and similar to `Snowden' at three of four locations. Specific gravity of B0564-8 and B0766-3 was significantly lower than that of `Atlantic' from both sources but within acceptable range for chip potatoes. B0564-8 tubers had the highest overall appearance ratings and the most consistent size and shape. B0564-8 and B0766-3 tubers had a significantly lower percentage of hollow heart and internal heat necrosis than `Atlantic' tubers. This resulted in overall better chip ratings for the numbered entries compared to `Atlantic' tubers. A potential fit for B0564-8 and B0766-3 in northeastern Florida production may be as a late season chip variety when the potential for the development of internal heat necrosis increases.