All indications point to a below-normal miller moth season in Colorado, according to a Colorado State University expert. The 2006 miller moth flight began in parts of Eastern Colorado about two weeks ago.
"Very low numbers of miller moths were present in 2005 – the lowest numbers in recent history," said Whitney Cranshaw, professor in the College of Agricultural Sciences and entomologist with Colorado State University Cooperative Extension. "This led to there being few moths laying eggs last fall, and subsequently, problems with the cutworm stage of this insect this spring were uncommon. A few scattered outbreaks were reported but there was not widespread occurrence of large numbers of caterpillars, the best predictor of the size of the later miller moth flight."
The hot, dry weather should also speed up the migration of miller moths – typically the adult form of the army cutworm – from plains to the mountains, leading to declining numbers in the latter half of June, Cranshaw said.
Drought conditions in Eastern Colorado have greatly reduced the amount of wild flowering plants. Consequently, miller moths will tend to be concentrated around flower gardens which could lead to increased miller moths in adjacent homes, Cranshaw said. However, many of the most common flowering plants that the moths might normally use are already long past bloom and no longer attractive. Russian olive trees are the most common plant still flowering that could attract miller moths.
For more information about miller moths, visit www.ext.colostate.edu/pubs/insect/05597.html