According to David Beresford, an entomology professor at Trent University, this is a rare event that only happens once or ...

The two broods - one in U.S. Midwestern states and the other in the South and Midwest, with a small area of overlap in Illinois - emerge together only once every 221 years.

David Beresford, UK managing director of Morse, said the company wants all shareholders to back the agreement. "In real terms we know we have acceptance from 85 per cent of shareholders. The ...