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Japanese beetle development seems to be a bit ahead of schedule this year, much like other pests we track each spring. Japanese beetle adults begin emergence when approximately 1,030 growing degree days (GDD; base 50°F) have accumulated since January 1 and will continue emerging until 2,150 GDD have accumulated. Japanese beetle adults likely began emerging in the southern portion of the state last week, and emergence will likely occur within the next two weeks in northern Iowa (Figure 1).