BOULDER, Colo. (AP) -- The University of Colorado has cut down 16 ash trees on its east campus in Boulder because they were infested with a destructive beetle called the emerald ash borer.
The Daily Camera reports the trees have been taken to the city forestry yards to be inspected. Untreated ash trees and ash wood in Boulder County have been under quarantine since Nov. 12, when the Colorado Department of Agriculture confirmed that an ash tree inspected by the city's forester was infested with the bugs.
The city has cut down six trees because of ash borers, which officials say have killed more than 50 million ash trees in 21 U.S. states since 2002. CU officials have found 21 trees on campus last month that showed symptoms of infestation.