New vineyard irrigation regimes will be developed that simultaneously enhance environmental sustainability and fruit quality for winemaking. The regimes will be tailored to selected rootstocks and will combine drip and sprinkler irrigation to conserve water, enhance the growth of floor vegetation to reduce pest and disease incidence, and promote a healthy soil microbial ecology. This research activity will also establish large long-term research plots for demonstrating to industry the responses of Merlot and Chardonnay winegrapes to combinations of rootstocks, irrigation regimes, and mycorrhizal inoculations.