Gypsy Moth (Lymantria dispar)

(Fig. 01)
Picture Notes: I found this, and dozens of other Gypsy Moths, in some bushes around the area of the Contact Mine, located on Pauline Mine Road in a ravine located about 10 miles northwest behind the town of Goodsprings, Nevada. It seems that I have been noticing more and more of the invasive cocoon nests on my hikes this year. Back East I notice that these infestations seemed to be more cyclically, about roughly every seven years. I wondering it it has something to do with them year because of the unusually hot past year and the fact that we are in a prolonged drought.

(Fig. 02)
Description: Lymantria dispar are moths in the family Erebidae. and are traditionally been referred to as "gypsy moths". Male gypsy moths (Lymantria dispar) are brown with a darker brown wing pattern, and have a 1.5 inch wingspan. Females are almost white, have dark saw-toothed patterns on their wings and are slightly larger. Gypsy moth larvae are black, furry caterpillars, with five pairs of blue dots and six pairs of bright red dots along their backs. It does damage during the caterpillar (larval) stage when it can eat as much as a square foot of leaves daily. Where there are many caterpillars, they defoliate trees, weakening and sometime killing them, increasing both fire an erosion potential.
(Fig. 03)
The gypsy moth have been an invasive species in the United States ever since their introduction in Medford, Massachusetts in 1888. Since then, Gypsy moths have since spread throughout the Northeast, Canada, and the Midwest, despite huge efforts to eradicate this pest. An outbreak of gypsy moth caterpillars can very quickly and effectively defoliate forests. Spread of this species represents a significant risk especially to hardwood trees, their preferred hosts, but since the gypsy moth has a wide diet, most types of trees are affected. Since 1980, the gypsy moth has defoliated about a million forested acres each year. Infestations occur cyclically, with populations reaching outbreak levels every 5-10 years.

It has been noted that agriculture an forestry agencies in Nevada are concerned about the potential infestation of the small white moth that can destroy entire groves of aspen, cottonwood and willow trees, especially in mountainous areas. Over the past few years there has been a 100-fold increase in their numbers. It's not clear whether such things as drought, wildfires, climate change or any other number of factors have contributed to the infestation. The gypsy moth is a notorious hitchhiker. The female lays her eggs during the late summer months on just about anything - trees, outdoor furniture, automobiles, trailers, campers, etc. and can be transplanted just about anywhere.

(Fig. 04)
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