The Nevada Department of Agriculture entomology laboratory is receiving a lot of inquiries about the high population of moths in northern Nevada. The moths are the adults of the army cutworm (Euxoa auxiliaris) an insect native to Nevada.
There were very high populations of the larvae in several areas of the West this year, including Nevada. We are now seeing the adults from those larvae.
The army cutworm overwinters as partially grown larvae (caterpillars) in the soil. They feed on a variety of plants for a couple of months when the weather warms up in the spring and may be pests of crops.
They pupate, then emerge as adult moths. The adult moths, often called millers, feed only on nectar and some pollen and therefore are not threat to gardens or crops.
It may appear that there are several species involved in this outbreak, but most are simply color variations of the army cutworm. The adults then migrate to higher elevations for the summer.
This is what we are currently seeing. Many are eaten by predators or die and the ones that do survive return to the valleys in the fall to lay eggs.
The eggs hatch and the larvae feed and grow until winter sets in.
The adults are attracted to lights at night. Changing the "color" of outdoor light bulbs can help reduce the number around businesses and homes. Yellow and amber colored lights are much less attractive to the moths.
If you have more questions contact Jeff Knight, Entomologist, Nevada Dept. of Agriculture (775) 353-3767 or (775) 848-2592.[[In-content Ad]]
