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Plastic mulch films contribute to improved crop yield and quality for vegetable and small fruit cropping systems. Although the single-season agronomic performance of conventional polyethylene mulches and soil-biodegradable mulches (BDMs) are similar, over time BDMs can begin to break down during storage and subsequently not provide season-long soil coverage. In this study, the changes in physicochemical properties of BDMs were investigated over 3 years of indoor storage (2015–18) under ideal environmental conditions in two laboratories. Mulches evaluated were black, 20–40 µm thick, suitable for annual vegetable production, and included three BDMs: two polybutylene adipate terephthalate (PBAT)-enriched mulches that are commercially available in North America, an experimental polylactic acid (PLA) and polyhydroxyalkanote-based film, and a conventional polyethylene mulch as a control. Tensile properties, specifically peak load and elongation at maximum tensile stress, decreased during storage, particularly for the PBAT-based BDMs, indicating a loss of strength. During year 3 of storage, the tensile properties declined extensively, suggesting embrittlement. The average molecular weight of PLA and PBAT slightly increased during year 1, perhaps due to release of monomers or oligomers, and then decreased extensively during years 2 and 3 due to hydrolysis of ester bonds (confirmed by Fourier transform infrared spectroscopic analysis). The structural integrity of BDMs was assessed during years 2 and 3 of the study (2017–18) in field trials at the locations where they were stored, Knoxville, TN, and Mount Vernon, WA, for vegetable production. The degradation of the BDMs during the cropping season was higher in 2018 compared with 2017, suggesting that degradation of mechanical and chemical properties while in storage may have contributed to rapid degradation of mulches in the field. In summary, BDMs undergo degradation even under ideal storage conditions and may perform best if deployed within 2 years of their receipt date. The farmer should verify that proper storage conditions have been used before receipt and that manufacturing date precedes the receipt date by no more than 6 months.

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.

Hard cider, made by fermenting apple (Malus ×domestica) juice, was at one time the most widely consumed alcoholic beverage in America. Largely abandoned after Prohibition, within the past 2 decades the rise in popularity of craft beverages has led to the reemergence of hard cider as an alternative to beer, wine, and spirits. Today, hard cider represents one of the fastest growing sectors within the craft beverage industry. The recent interest in cider presents additional marketing opportunities for apple growers and businesses currently involved in, or considering entering, the apple cider or craft beverages industries. However, the lack of a strong history or experience in selecting, producing, and using cider apples poses a significant challenge to this emerging market. This article reviews the current state of research in cider apple production, including economic feasibility, mechanized management, and cultivar evaluation and improvement.