Moths around the house                                                                             | Printer-Friendly Format |

SIOUX FALLS, SD – High numbers of miller moths are being reported around the state and may signal future
outbreaks for some important pest species.

Ruth Beck, Hughes and Stanley County Agronomy Educator, reported last Thursday (June 14) about large
numbers of army cutworm moths being observed in the siding and eaves of a house.

Craig Rosenberg, Minnehaha County Agronomy Educator reported yesterday (June 18) that he was getting
phone calls from homeowners about moths on trees, lawns, and buildings.

The moth species that are currently being observed in South Dakota are army cutworm moth, forage looper
moth, armyworm moth, and sod webworm moth.

Army cutworm moths are the adult stage of cutworms that fed on winter wheat and alfalfa in the early
spring; these moths naturally migrate to the Rocky Mountains to spend the summer before coming back to
the Plains in the fall.  Army cutworm larvae are a common pest of winter wheat and alfalfa in South Dakota.

Forage looper larvae are not considered economic pests in the state although they are common on alfalfa in
the summer.  Clover, ragweed, grasses, and several other plant species are also known host plants.

Armyworms (not the same as army cutworms) can be a devastating pest of small grains and corn.  The
presence of high numbers of these moths right now is a cause for concern.

Small grains and corn growers will need to be vigilant in scouting for armyworm larvae from now until the
crops are harvested. 

Economic thresholds and many insecticide options are available for controlling armyworm larvae in small
grains and corn.  The armyworm moths currently being seen around the house most probably migrated
from southern states; they are not known to overwinter in South Dakota.

Sod webworms are a common pest of lawn grass in South Dakota.  Larvae clip and web together blades
of grasses and may cause extensive damage to lawns especially during drought.  Over 20 species of sod
webworms are native to South Dakota open rangelands.

Links to Iowa State University Entomology:  Biology and Moth ID

© Copyright 2009 by South Dakota State University.  All Rights Reserved.

 Web Posted on Tuesday, June 19, 2007 by Mike Catangui. Last Updated on Tuesday, June 19, 2007.