Studies using extremely high rates of oils in Virginia indicated the oils reduced photosynthesis and delayed maturity of wine grapes. Recent work using commercial spray equipment and typical rates for California grape production show no adverse effects although high rates did reduce stomatal conductance. JMS Stylet Oil has become an important part of Sonoma County IPM programs and these data suggest that the treatment at normal label rates has no impact on wine grape maturity.

Attached are files detailing results including the 2009 Alexander Valley Chardonnay Oil Project and work done last year on the Central Coast. Laura Breyer notes that, "Battany’s work is interesting in the conclusion that the application method effects the outcome."