MILWAUKEE— If it seems like yellowjackets are suddenly everywhere, there’s a reason and the time of year has a lot to do with it.
Dr. Chelsea Cook, an assistant professor of biological sciences at Marquette University, says an early and relatively mild spring likely gave yellowjacket queens a head start. Queens typically spend the winter sheltered in places like leaf litter beneath the snow before emerging in the spring to begin building their nests. Without a late cold snap to interrupt that process, Dr. Cook says colonies had more time to grow.
Now, as summer winds down, those colonies are reaching their busiest period. Worker yellowjackets are spending much of their time collecting food to support the colony as it produces reproductive females and males…