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Zai Q. Yang, Yong X. Li, Xiao P. Xue, Chuan R. Huang, and Bo Zhang

damage to facilities and provide the scientific basis for wind damage prevention and practical greenhouse designs. The wind tunnel test, which is an advanced technique employed in the study of wind pressure distribution on the surface of a building

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Carol Miles, Russ Wallace, Annette Wszelaki, Jeffrey Martin, Jeremy Cowan, Tom Walters, and Debra Inglis

, manufacturers, marketers, etc.) have created standards to define degradation and established widely accepted testing strategies to evaluate the behavior of degradable products [American Society for Testing and Materials/Institute for Standards Research ( ASTM

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Lauren C. Garner and Thomas Björkman

Excessive stem elongation reduces plant survival in the field and hinders mechanical transplanting. Mechanical conditioning is an effective method for reducing stem elongation during transplant production. This investigation examined the consequences of mechanical conditioning, using brushing and impedance, on subsequent field performance of tomatoes (Lycopersicon esculentum Mill.). Mechanically conditioned transplants of processing tomatoes resumed growth after transplant shock as quickly as did untreated plants, and subsequent canopy development was also equal. In 4 years of field trials, yield was not reduced by mechanical conditioning. Transplants for fresh-market tomatoes may be more sensitive to injury than those for processing tomatoes because they flower sooner after the conditioning treatments. Nevertheless, neither earliness nor defects in the fruits of the first cluster were affected by mechanical conditioning. Early and total yields were equal in both years that fresh-market crops were tested. Thus, there were no adverse effects on field performance of either processing or fresh-market tomatoes as a result of reducing stem elongation by mechanical conditioning before transplanting. Improved wind tolerance was tested both in a wind tunnel and in the field. In wind-tunnel tests, brushed and impeded plants resisted stem bending at wind speeds 4 to 12 km·h–1 higher than did untreated plants. A 70 km·h–1 wind after transplanting killed 12% of untreated plants but only 2% of treated plants. Mechanical conditioning with brushing and impedance produced transplants with desirable qualities without adverse effects on field performance.

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Xin Zhao and Edward E. Carey

SAS (version 9.1; SAS Institute, Cary, NC). Multiple comparisons were conducted using Fisher's least significant difference test (α = 0.05). Results and discussion Wind speed inside the high tunnels was consistently reduced relative to the outside by

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Sharon J.B. Knewtson, M.B. Kirkham, Rhonda R. Janke, Leigh W. Murray, and Edward E. Carey

, materials, and other features vary. High tunnels are used to modify the crop environment allowing season extension (early or late), some exclusion of rain, wind, and insects as well as enhanced crop quality and yield ( Lamont, 2005 ). Protected agriculture

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Karen L. Panter, Timmothy M. Gergeni, Casey P. Seals, and Andrea R. Garfinkel

freezing temperatures, rain, wind, hail, and in some cases, disease ( Lamont, 2009 ; Wien, 2009a ). The increased interest in domestic production of cut flowers and herbs in high tunnels and the advantages of high tunnel production create the need for

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Sharon J.B. Knewtson, Rhonda Janke, M.B. Kirkham, Kimberly A. Williams, and Edward E. Carey

. Producers use high tunnels to modify crop environment. The primary function is to elevate temperatures to allow earlier planting in the spring, earlier ripening, and extend fall harvests ( Kadir et al., 2006 ; Lamont, 2005 ). Other benefits include wind and

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Russell W. Wallace, Annette L. Wszelaki, Carol A. Miles, Jeremy S. Cowan, Jeffrey Martin, Jonathan Roozen, Babette Gundersen, and Debra A. Inglis

, sunlight intensity, daylength, humidity, wind speeds, and elevation among other factors. During the winter months, high tunnels provide microclimates suitable for season extension allowing growers to plant lettuce earlier in the season, later in the season

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David S. Conner and Kathleen Demchak

said raspberry production would not be possible without tunnels. Tunnels were credited with protecting against cold as well as many extreme or unusual weather events such as hail, wind, torrential rain, and unexpected cold snaps. They also were found to

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Analena B. Bruce, Elizabeth T. Maynard, Julia C.D. Valliant, and James R. Farmer

by high winds and never replaced. In the interviews and on tours of their high tunnels these growers described not having time to harvest all the crops produced in their high tunnels and not finding sufficient time to maintain the tunnels to their