Reader Refutes Guest Writer’s Claim
By Dave Hanson (Sheridan, Oregon)
I am not directly involved with winegrowing but I am an avid wine drinker, a supporter of Oregon wines and an interested reader of your publication. I couldn’t help but notice the glaring falsehood that was stated in the guest column by Evan Bellingar in the August 2009 Oregon Wine Press.
In his article, “Staying a LIVE Vineyard,” he states that sulfur used as a pesticide is broad spectrum: It does not discriminate between pathogenic fungus and beneficial predatory mites.
He then claims that unlike sulfur, selective synthetic pesticides target powdery mildew (a fungi) and leave our insects and animals alone. Specifically he states that, “The cell walls of fungi are composed of chitin, a substance not found in plants or animals.”
Nothing could be further from the truth. Chitin, while it is the main component of some fungi cell walls, is also the main component of exoskeletons of insects, including ants, beetles and butterflies. In defense of his company’s practices of using synthetic pesticides, Mr. Bellingar gives the misleading impression that organic practices are carpet-bombing the vineyards while synthetic pesticides are “laser-guided” to zero in on chitin found only in fungus, like powdery mildew.
He was using this point to disparage certain practices in favor of practices that his business uses (synthetic pesticides) and claiming that those practices were superior for their selective targeting of fungi while avoiding collateral damage to other organisms.
The fact is the synthetics that focus on chitin are broad spectrum and kill insects of many types because they, too, are composed of chitin. ◊