Issue link: http://winesandvines.uberflip.com/i/347498
74 p r a c t i c a l w i n e r y & v i n e ya r d a U G U S t 2 0 1 4 g r a p e g r o w i n g vine on the property regularly. Staff train- ing is an important part of an IPM pro- gram. They identify powdery mildew outbreaks and alert me to potential insect problems, although the insects they iden- tify are seldom a problem. "My staff and I all like the mineral oil- based program more than a sulfur pro- gram," Kenworthy concludes. "One downside is an increasing presence of erineum mites. I see more each year, but I am not ready to change my spray pro- gram and incorporate sulfur treatments in an attempt to suppress erineum mite populations, as they seem more of an aes- thetic (problem) than an actual problem." Robert Young Vineyards Robert Young Vineyards practices inte- grated pest management (IPM) in 316 acres of vineyards in Alexander Valley that include Chardonnay, Cabernet Sauvignon, Riesling, Sauvignon Blanc, Merlot, Melon, Malbec, Viognier, Pinot Blanc, Petit Verdot, Zinfandel and Cabernet Franc. Jim Cuneo, assistant vineyard manager, and Jim Young rely on reduced-risk pesti- cides in their vineyards with labels of caution or less. Three weather stations in the vineyards provide data for the pow- dery mildew model to extend spray intervals when the pressure is low and the weather forecast is favorable. The biggest change in the pest-manage- ment strategy began in 2001, when Cuneo treated 20 acres with JMS Stylet Oil. Results were good, so 60 acres were treated the next year, then the entire farm. Cuneo combines 1% Stylet mineral oil with fungicides that are applied with an electrostatic sprayer. The program has reduced powdery mildew, spider mite and grape leafhopper populations to non-economic levels as a result. Cuneo has shared his experience with Alexander Valley growers, and Laura Breyer (pest control advisor) shared the results at grower IPM meetings through- out Sonoma County. There have been sig- nificant increases in mineral oil application as a result. Only alternate tractor rows are culti- vated while retaining a permanent cover crop in the other tractor row. This is pri- marily to allow for wet weather access and erosion control, but also to provide an environment for beneficial insects to reside. Mowing is typically done twice, once in late spring and pre-harvest unless conditions require additional mowing. The cover crop in the tractor rows are rotated every four to five years and seeded with a native grass blend in the permanent rows and a legume-based organic soil-builder blend in the culti- vated rows. Cuneo has not purchased beneficial insects for release in the vine- yard, but he would do so if the need arose. Breyer has observed that reduced-risk pesticides—and JMS Stylet Oil in partic- ular—are often easy on beneficials. Breyer says, "My experience is that vine- yards that switch from sulfur to mineral oil see a resurgance of predatory mites. More plentiful beneficials and the sup- pressive effect of mineral oil on pest populations make a good combination." Cuneo observed increases in erineum mites after several years with no sulfur applications. While uncertain that erineum mites cause economic damage, effected vines are aesthetically undesirable due to the close proximity of vineyards to the winery tasting room. As a result, the first two sprays after budbreak are wettable sulfur and then mineral oil is applied along with fungicides. In addition, vineyard workers are trained to remove leaves with blister symptoms when shoot-thinning or leaf- ing. This has limited erineum mite infesta- tions to the lower leaves in the canopy. "Rebalancing an IPM program must be done as pest pressures change from year to year," Cuneo concludes. PWV BEVILL VINEYARD MANAGEMENT LLC est. 1975 // SONOMA COUNTY, california e INFO@BEVILLVINEYARD.COM t 707.433.1101 w WWW.BEVILLVINEYARD.COM V I N E Y A R D S o f D I S T I N C T I O N