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To optimize pesticide applications to the canopies of deciduous perennial crops, spray volume should be adjusted throughout the year to match the changes in canopy volume and density. Machine-vision, computer-controlled, variable-rate sprayers are now commercially available and claim to provide adequate coverage with decreased spray volumes compared with constant-rate sprayers. However, there is little research comparing variable- and constant-rate spray applications as crop characteristics change throughout a growing season. This study evaluated spray volume, spray quality (e.g., coverage and deposit density), and off-target spray losses of variable- and constant-rate sprayers across multiple phenophases in an apple (Malus domestica) orchard and a grape (Vitis vinifera) vineyard. The variable-rate sprayer mode applied 67% to 74% less volume in the orchard and 61% to 80% less volume in the vineyard. Spray coverage (percent), measured by water-sensitive cards (WSC), was consistently greater in the constant-rate mode compared with the variable-rate mode, but in many cases, excessive coverage (i.e., over-spray) was recorded. The variable-rate sprayer reduced off-target losses, measured by WSC coverage, up to 40% in the orchard and up to 33% in the vineyard. Spray application deposit densities (droplets per square centimeter) on target canopies were typically greater in variable-rate mode. However, the deposit densities were confounded in over-spray conditions because droplets coalesced on the WSC resulting in artificially low values (i.e., few, very large droplets). Spray efficiencies were most improved early in the growing season, when canopy density was lowest, demonstrating the importance of tailoring spray volume to plant canopy characteristics. [ABSTRACT FROM AUTHOR]

The measurement of pesticide spray losses from air blast sprayers as they apply to tree crops is required to provide the industry with information on sprayer efficiency. Spray loss, however, is often difficult to measure using current standardized methods. Test procedures are often time consuming and too costly to be extensively used. To facilitate sampling of spray losses during application to tree crops, a device consisting of an adjustable metal frame and a grid has been developed. The grid supports artificial targets. The frame stands in the vineyard or orchard over two adjacent rows, allowing the sprayer to pass below the structure, while applying a predetermined spray volume rate. Spray deposit on the collectors enables assessment of the amount of spray droplets dispersed in the atmosphere around the plant target. On one hand, the system aims to develop an alternative procedure to the presently proposed ISO methodology (DIS 22369.2)for classification of orchard/vineyard sprayers according to drift risk. On the other hand, it could facilitate the study of the spray mass balance discharged to target plants, ground, and atmosphere, integrating ISO standard CD 22522 concerning field measurement of spray distribution in tree and bush crops. This article reports the first experimental results related to the use of the device. [ABSTRACT FROM AUTHOR]

The first vintage from Passing Time earned high marks from wine critics; will sales follow? [ABSTRACT FROM PUBLISHER]

Just waiting to see if there's a happy hour going on [ABSTRACT FROM PUBLISHER]