RAPID CITY, S.D. (AP) — A new aerial analysis of the Black Hills National Forest shows the pine beetle epidemic is still growing but slower than before.

The Rapid City Journal reports the survey filed by state and federal agencies found that about 16,500 acres were newly identified last year as affected by mountain pine beetles.

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The U.S. Forest Service says that’s a sign the epidemic is slowing, after 34,000 acres were newly affected in 2013.

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Since the outbreak began in 1996, about 438,000 acres have been impacted by pine beetle infestations.

Since 2012, South Dakota has dedicated $10 million to fight the beetle on private, state and federal lands. Wyoming has invested $5 million over the past four years.

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