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120 W i n e s & V i n e s n O V e M B e r 2 0 1 4 Franc; PB removal reduced crop yield by 40% and berry weight by 19% in Petit Ver- dot. High and PB removal increased pH and reduced TA in Cabernet Franc; high leaf removal reduced Brix and TA in Petit Ver- dot. Cabernet Franc berry anthocyanins did not differ between control, PB and medium removal treatments; however, medium had 19% greater anthocyanins than the high removal treatment. Treatment did not affect anthocyanins in Petit Verdot. PB removal increased total berry phenolics by 16% and 22% in Cabernet Franc and Petit Verdot, respectively. results suggest that pre-bloom fruit-zone leaf/lateral removal can reduce crop yield and berry weight, loosen clusters and lead to higher berry phenolics, perhaps due to longer seasonal fruit exposure or smaller berries. Under-trellis management The rapidly growing vinifera grape industry in the Finger Lakes region of upstate New york is concentrated on the hillsides di- rectly adjacent to the lakes, raising concern of pollution from runoff and leaching of nutrients and agrochemicals. The standard vineyard floor-management practice in the region is permanent vegetation between rows, with an herbicide strip approximately 1 meter wide under the trellis. Cover crops grown under the trellis have the potential to reduce erosion, improve soils and limit pollution of local watersheds. Adam Karl et al. of Cornell University in Ithaca, N.y., looked at under-trellis management impacts on agrochemical and nutrient leaching in a Finger Lakes vineyard. Four under-trellis management systems were established in a Cabernet Franc vine- yard in Lansing, N.y., in 2009: glyphosate herbicide (gH), cultivation (CULT), native vegetation (NV) and white clover (Trifolium repens) seeded annually at 10 pounds per acre (WC). Drainage lysimeters were in- stalled beneath the under-trellis treatments to monitor nutrient and pesticide concen- trations in leachate water samples. In 2012, N leachate concentrations from the WC treatment were 349% and 281% greater than that of NV and CULT, respec- WineEast grapegrowing Does cluster thinning improve composition? W hile many winemakers on the West Coast urge cluster thinning to increase wine quality, does the same practice work in the East? Shijian Zhuang et al. from Michigan State University, East Lansing, examined the impact of cluster thinning and basal leaf removal on Cabernet Franc fruit quality. Two levels of cluster thinning (low and high) and basal leaf removal (yes or no) were imposed on Cabernet Franc vines in southwest Michigan at three phenological stages over a two-year period. Leaving a high crop increased yield, cluster number, cluster weight and berries per cluster (one year only), and ravaz Index. There was no treatment impact on Brix, TA or pH. High crop reduced anthocyanins and phenolics, as did leaf removal. The authors concluded that cluster thinning was a useful tool for reducing crop load (ravaz Index), but it did not improve basic berry composition, hence merely reduced economic return. A.R.