The mountain pine beetle problem is worsening in the Black Hills National Forest.

U.S. Forest Service spokesman Frank Carroll says that beetles have now damaged trees on more than 405,000 acres in the 1.2 million acre forest in southwest South Dakota and northeast Wyoming.

Carroll says the beetles that have killed millions of trees in the Mountain West in recent years are in "an explosive cycle." Crews in Custer State Park expected to find about 15,000 infested trees during an annual survey but instead found 142,000.

Gov. Dennis Daugaard is working with the park and forestry experts to develop a plan to remove infested trees before new bugs hatch and spread next summer.

Associated Press

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