It’s true! Each year it rains viruses, more than a trillion of them per acre over thousands of forested acres in the USA. This is the work of the airborne arm of the USDA Forest Service, part of their efforts to reduce the devastation to hardwood forests caused by the imported gypsy moth, Lymantria dispar. Each year they spray with a registered “general use pesticide” called GYPCHEK, the active ingredient of which is Lymantria dispar multinucleocapsid nuclear polyhedrosis virus (LdMNPV), an ideal ‘green’ pesticide. The virus is host-specific, self-replicating, biodegradable, and deadly. And I would add, it makes a most interesting story, provided you’re not a caterpillar.
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