See under Vine Tears.
Term (also vine water, vine blood) for the water-like wound sap that emerges in spring as a reaction to pruning. This is a protective mechanism in plants, because the sap contains highly effective disinfectants that prevent the penetration of bacteria and close the cut wounds with a resin plug. However, wounds inflicted on the plant during pruning, which is usually carried out during hibernation, do not start to "bleed" until the beginning of...
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Diplom-Sommelier, Weinakademiker und Weinberater, Volders (Österreich)