Elm%20Spanworm

Elm%20Spanworm (Ennomos%20subsignarius) - Elm%20spanworm%2C%20is%20a%20native%20geometrid%20moth%20whose%20polyphagous%20larvae%20feed%20on%20many%20species%20of%20hardwood%20trees%2C%20especially%20hickory%2C%20oak%2C%20and%20ash.%20It%20is%20most%20important%20as%20a%20forest%20pest%20in%20the%20Appalachian%20Mountains%2C%20from%20Pennsylvania%20south%2C%20but%20an%20urban%20forest%20outbreak%20has%20also%20occurred%20in%20St.%20John%27s%2C%20Newfoundland%20and%20Labrador.%20This%20species%20overwinters%20as%20eggs%2C%20which%20are%20laid%20in%20clusters%20on%20the%20bole%20and%20on%20the%20underside%20of%20branches.%20Eggs%20hatch%20in%20early%20spring%20and%20young%20larvae%20feed%20on%20the%20lower%20surfaces%20of%20leaves%2C%20producing%20%22shot-hole%22%20damage.%20Older%20larvae%20consume%20the%20whole%20leaf%20apart%20from%20the%20major%20veins.%20After%20developing%20through%20five%20instars%2C%20larvae%20pupate%20in%20loose%20silk%20cocoons%20formed%20on%20the%20partly%20eaten%20foliage%20and%20in%20bark%20crevices.%20Outbreaks%20of%20this%20species%20occur%20at%20irregular%20intervals%20that%20defoliate%20trees%20over%20wide%20areas.



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