Analysis of information sources in references of the Wikipedia article "Brood XIX" in English language version.
Both Brood XIX and XIII exist in Macon, Sangamon, Livingston and Logan counties in Illinois. The easily accessible place they come closest to overlapping is Springfield, Illinois, which is in Sangamon County.
Brood XIX and Brood XIII will both emerge this spring. The last time these bugs showed up at the same time in the United States, Thomas Jefferson was president. After this spring, it'll be another 221 years before the broods, which are geographically adjacent, appear together again.
Both Brood XIX and XIII exist in Macon, Sangamon, Livingston and Logan counties in Illinois. The easily accessible place they come closest to overlapping is Springfield, Illinois, which is in Sangamon County.
Brood XIX and Brood XIII will both emerge this spring. The last time these bugs showed up at the same time in the United States, Thomas Jefferson was president. After this spring, it'll be another 221 years before the broods, which are geographically adjacent, appear together again.