PT - JOURNAL ARTICLE AU - James A. Taylor AU - Terence R. Bates TI - Sampling and Estimating Average Pruning Weights in Concord Grapes AID - 10.5344/ajev.2012.12069 DP - 2012 Dec 01 TA - American Journal of Enology and Viticulture PG - 559--563 VI - 63 IP - 4 4099 - http://www.ajevonline.org/content/63/4/559.short 4100 - http://www.ajevonline.org/content/63/4/559.full SO - Am. J. Enol. Vitic.2012 Dec 01; 63 AB - Pruning weights are a useful indication for growers of vine size within their production systems. However, pruning weights are rarely collected in commercial situations, as there is little information to help growers determine how many samples to measure. An intensive study of individual vine pruning weights was undertaken over three years in a Concord (Vitis lambruscana Bailey) block at the Lake Erie Research and Extension Laboratory, New York. The population variances associated with individual and aggregated neighboring vine measurements were used to determine random sampling schemes to assist growers. A sampling scheme based on 23 random interpost samples (3-vine sampling) is suggested as a good compromise to minimize the time associated with sampling and to maximize the accuracy of measurement and the value of the information. A spatial analysis of the variance indicates that the same sampling scheme could be extrapolated to block sizes larger than the survey area (0.93 ha), provided that the management and environmental conditions can be considered uniform over the larger block.