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W i n e s & V i n e s A P R i L 2 0 1 4 35 145 Jordan Street • San Rafael, CA 94901 • 415-457-3955 • Fax 457-0304 • www.boswellcompany.com targeting the fine roots beneath the emit- ters. This means short, slightly more fre- quent irrigations around six to eight hours in medium-textured soils twice per week. Long soaks may not be effective because deep roots will be fairly inactive unless the season starts with a full soil profile. In gen- eral, once the lower soil profiles dry out from plant water use, it is hard to replen- ish the moisture supply in an effective way. Remember that a smaller crop is likely to ripen sooner. Be in close contact with your winery customers so that no one is sur- prised by sudden ripening. It also isn't unusual for smaller crops to mature at lower sugar levels. Tasting fruit, examining seeds for ripeness and picking by pH and titratable acidity rather than degrees Brix are going to be important ways to deter- mine ripeness. Harvest and post-harvest If you successfully bring in a decent crop of high quality fruit, start by irrigating yourself with a good glass of wine or beer! Bringing the crop in with a limited amount of irrigation is a great accom- plishment worth celebrating. Then, if you have any water left over, think about post-harvest irrigation, especially if there is still growing season left, and the vines still have green leaves. This helps to set up a healthy start for the next year and also protects vines from winter kill due to cold temperatures and dessication, which is sometimes a problem in the colder grow- ing regions. On the other hand, if long- term weather forecasts are calling for dry weather, you may want to hold on to whatever water you have available as a hedge on water security. Final thoughts My Australian friends noted that they have been surprised at how tough and drought resistant grapevines have proven to be. To keep vines alive they have dropped fruit, pruned vines severely and just taken their chances. When water became available again, many of the vineyards resumed a normal growth pattern and started to produce regular crops. It is important to remem- ber that many vineyards in Australia are on their own roots, and they use vigorous rootstocks when rootstocks are needed. They plant drought-tolerant vineyards for the most part and use less water than most American winegrowers—they always have and always will. They tend to avoid rootstocks with Vitis riparia in the parentage, as these rootstocks per- form poorly under dry conditions such as 101-14, SO4, 5C. Droughts are likely to happen as the west goes through climate cycles. Planning for it with vineyards that are more drought resistant (variety and rootstock choice), developing more water storage both on a farm and on a regional basis and learn- ing how to use water as carefully and pre- cisely as possible are all future practices to consider. Glenn McGourty is the UC Cooperative Extension winegrowing and plant science advisor for Lake and Mendocino coun- ties. He also tends a 1-acre vineyard of the aromatic Italian wine grape variety Arneis on his property along the Russian River near Ukiah, Calif. Special thanks to my friends from Australia who contrib- uted information to this article: Michael McCarthy, PIRSA-SARDI, Barossa Val- ley, SA; Chris Penfold, University of Ade- laide, Roseworthy, SA; Glyn Ward, Dept. of Food and Agriculture, WA; Ian Good- win, Dept. of Environment and Primary Industries, VA; Peter Dry, University of Adelaide, Waite, SA. g R A P E g R O W I N g