Welcome and AnnouncementsNick Frey, Sonoma County Grape Growers Association’s Executive Director, and meeting director Laura Breyer welcomed new and returning participants to the 6th year of Grower Appellation Meetings. Held once a month during the growing season in Alexander Valley, Dry Creek Valley, Russian River Valley, and Sonoma Valley we have an agenda of timely viticultural topics to facilitate participatory discussions. Over 130 people attended the sessions this month.Announcements included: Upcoming Code of Sustainable Winegrowing session on June 21 at the Kendall-Jackson Wine Center will cover the chapter on energy efficiency. The California Department of Pesticide Regulation has a new statewide policy concerning pesticide violations. In short, as our local enforcement agency the Ag. Commissioner’s office will have clearer direction as to when violators will receive a written notice of non-compliance and/or fine, and fines will be applicable where they previously were not. Call the Ag Commissioner’s office at (707) 565-2371 or visit their website at www.sonoma-county.org/agcomm and see their “What’s New” section. Professor Andy Walker at UC Davis is looking for vineyards planted on 039-16 rootstock that are scheduled to be removed. He is investigating the population of nematodes remaining after long-term exposure to the nematode resistant rootstock.Old BusinessOur last regular meeting was in July 2005 and participants reported the season ended up well in general with better than expected yields and good quality. We discussed the merits of a strict tons per acre versus a balanced vine approach to crop management, consensus favoring the latter. Some folks who have been analyzing dormant buds predict a lighter crop for this coming season.Several growers reported late season botrytis issues, particularly in zinfandel, and a few green mold (Cladosporium) incidents.Mealybugs (grape and obscure) were more problematic for a number of growers and required treatment. Earwigs may be mealybug predators.Last year’s glassy-winged sharpshooter (GWSS) finds in North Coast ornamental nursery shipments were traced to a supplier’s new facility in a GWSS hotspot, and that situation was dealt with so that no further finds occurred in 2005.Pierce’s disease outbreaks in new vineyards noted late summer last year may indicate an upswing in the PD cycle.A few growers had late season mite issues, while most others noted a light mite year. Review Cooperator’s Blocka) Russian River Appellation—Host Dennis Devitt at Laguna Ranch With the unseasonably cold wet weather, little activity was occurring in the vineyards. Dennis did report deer and orange tortrix damage to the slowly growing buds. Oil + copper will be used if the tall cover crop instigates thrips issues, since the oil/Cu will also help eradicate any incipient mildew. Other growers have seen earwig damage on buds.b) Sonoma Valley Appellation—Host Pat Herron at Barricia Vineyard Barely at the Q-tip stage with this unusually late winter-like weather. c) Dry Creek Valley Appellation—Host Richard Rued at Rued Vineyard Chardonnay has been out 2” since February, but has stalled in growth.d) Alexander Valley Appellation—Host Dana Grande at Jordan Vineyard Vineyards still very wet, and vines are slow to push.General Topics Mildew - The overwintering structures called cleistothecia burst and emit ascospores, which begin mildew infections if they land on unprotected green tissue. The infections remain microscopic until temperatures warm up and the colonies begin to grow. Wet springs like this year increase the chance of early infection because of the difficulty of getting tractors into vineyards, and material being washed off with following rains. Backpacking the material on, or the small, ATV-pulled tanks can pay off later season. If neither of these options is practical for a grower, then using an eradicant like JMS Stylet-oil with a strobilurin or DMI may be a good first treatment choice. Sulfur / copper mixes can also be a reasonable first treatment option, but the strobi’s and DMI’s have longer residual and are locally systemic, and many growers place more confidence in the oil’s ability to eradicate. Oil is incompatible with sulfur. Organic options would include an organic oil formulation either alone or with Serenade or Sonata, or an oil + Kaligreen application, or Nordox + Kumulus. The March 2006 Viticultural Newsletter from Sonoma County UC Cooperative Extension addresses early season mildew in better detail. Phomopsis – Late spring rains in 2005 caused more phomopsis infections farther out on canes than has been seen in many years. In chronically affected areas phomopsis can cause stunted shoots and yield reduction due to devigorated spurs or canes from previous years’ infections, and shoots that become diseased grow poorly with newly infected tissue. Another aspect of phomopsis is the role it may play as an agent in the dead arm disease complex. Eutypa is our best-known dead arm fungus, but phomopsis is also known in other viticultural areas to cause similar decline. Sanitation can be a good management tool against phomopsis. When pruning, look for the bleached 1-year-old wood and prune it out. Dormant lime sulfur helps control the disease, as does protecting the green shoots before rain events. The spores are spread with rain and a number of the strobilurins can help protect against infection. Symptoms show up about 2 weeks after infection. Chardonnay and viognier seem particularly susceptible.Dithane is inexpensive and as effective as some of the strobilurins, but is on the wane as a popular fungicide due to potential human health risks. An Australian research article found the maneb classes had an adverse impact on predatory mites.When spraying, watch for standing water that might drain off site to contaminate streams. Resistance Management – Repeated use of pesticides with similar chemistries can promote the development of resistance by the pest to the material. For instance, the new material Scala is used against botrytis, but is the same class of fungicide as Vangard. The Fungicide Resistance Action Committee (FRAC) has excellent information on the subject of resistance and detailed information about the fungicide classes at their website, and the UC IPM website has a 2006 updated PDF document on the Efficacy and Timing of Fungicides, listing relative efficacies of our fungicides on mildew, botrytis, eutypa and phomopsis, as well as including the fungicide class number for easy reference. Weed Management – The new herbicide Chateau has been used successfully as a pre-plant treatment and growing season treatment by a number of growers. Remember to read the Supplemental Label for grapes before using on young vineyards, as there are specific recommendations on the label when used in a vineyard less than 2 years old. This year, like last, will be challenging for weed management with the amount of rain providing vigorous growing conditions for weeds as well as vines. Heads up GWSS – A new find in ornamental nursery shipment by county inspectors this year. The GWSS grower initiated trapping program continues this year with coordination by SCGGA. Vine Mealybug – Research has shown VMB can survive in unfermented pomace. Covering pomace piles with clear tarps (black tarps are not as effective) for at least two weeks reduces viability by 99%. Complete composting should be an effective alternative Gophers – Activity is beginning. Owl boxes should be cleaned in mid-July.What is it? A very healthy looking panicle willowweed specimen was brought in by one grower who noted it was difficult to control with Roundup.Adjourn - Thanks for coming!