The cool temperatures and rainfall have delayed planting, flowering and insect emergence, but two of our late-spring arrivals are finally ready to put in an appearance; the Japanese beetle and lightningbugs.
Japanese beetle adults have been observed in southern and central Iowa. We don’t know what the population abundance will be this year but they here, though off to a slow start.
The slow start to Japanese beetle emergence was discussed in the June 17, 2019 Integrated Crop Management News. The Growing Degree Map included in the ICM article suggests it will take many warm, dry days before adults emerge in northern Iowa.
See our HHPN Encyclopedia article on Japanese beetle for details on appearance, damage and management options.
We continue to monitor the locations of the Japanese beetle in Iowa. See map below. If you observe adults in a county where they have not yet been reported, please send images to insects@iastate.edu. List the location and date in your message.
Links to this article are strongly encouraged, and this article may be republished without further permission if published as written and if credit is given to the author, Horticulture and Home Pest News, and Iowa State University Extension and Outreach. If this article is to be used in any other manner, permission from the author is required. This article was originally published on June 21, 2019. The information contained within may not be the most current and accurate depending on when it is accessed.