Cover crop water use in relation to vineyard floor management practices

The aim of our study was to compare soil evaporation (Es) versus cover crop (Festuca arundinacea var. barfelix) evapotranspiration (ETcc) within a vineyard ecosystem and to investigate the effect of mowing in reducing cover crop evapotranspiration, and, hence, its below-ground competitiveness. The study was carried out in a 2-year-old Sangiovese (Vitis vinifera L.) vineyard, grafted to SO4, in Bologna, Italy. Mini-lysimeters and a portable gas-exchange chamber system were used to investigate cover crop evapotranspiration in relation to mowing and bare soil management practices. Our results show that, immediately after mowing, ETcc markedly decreased, with the percentage of reduction ranging from 35 to 49%, depending on the amount of clipped biomass. The extent of the ETcc reduction decreased over time as the cover crop regrew. Over the 28-day period following the mowing, soil evaporation was 35 and 48% lower than mowed and unmowed cover crop evapotranspiration, respectively. This study shows that mowing could be used as a water management strategy to decrease vine cover crop competition over a short time period.