People in many areas in central and south Minnesota, including the Twin Cities have been witnessing large numbers of medium sized brown moths flitting about in their yards and around their homes. Because there are so many moths, there is a lot of concern about potential damage they might cause. However, these insects, green cloverworm moths, Hypena scabra, are only nuisances.
|Typical green cloverworm moth. Note the snout and the|
white wavy pattern on the wings. Photo: Duane Kunkel
These moths can partially be identified from the conspicuous snout on their heads. Also look closely at their wings. These moths have a wingspan of about an inch to almost an inch and a half. When at rest, they often hold their wings in a delta shape, although this varies as wings are also held closer together. Their forewings are narrow and are generally dark brown or grayish with a wavy pattern of white. The exact coloration is often variable. The hind wings are broad and dark colored.
Green cloverworm moths do not survive winters in Minnesota but do migrate into the state each spring so they are always seen to some extent. They can have two generations in a year and can be seen throughout the growing season. This year, their numbers have been particularly high, especially now during late summer.
|Green cloverworm moth showing variation in color. |
Photo: Brenda DeBlieck
The larvae feed on a wide variety of plants, including alfalfa, beans, clover, ragweed, strawberries, raspberries, elm, hackberry, and willow. They can be a sporadic pest in agriculture; this year the caterpillars were sprayed in a few fields of dry beans and soybeans, although it was unnecessary to treat them in most fields.
Fortunately, green cloverworms are not a pest in urban areas. While they feed on a wide variety of plants, they are not known to be a pest on landscape or garden plants. The moths are nothing more than a nuisance; just ignore them and wait for them to go away on their own. Remember, they do not survive the winter in Minnesota, all life stages will die by the time winter arrives.
For more information and pictures, see the Moth Photographers Group and BugGuide web sites.