The Beetles

• The mountain pine beetle lives under the bark of pine trees in western North America, feeding on and killing them. Unusually hot, dry summers and mild winters can lead to large-scale epidemics.
  
  

Harvesting

• According to a Sept. 6, 2009, story in the Rapid City Journal, titled "Custer State Park Bug Battle To Limit Trail Use, Change Forest," park officials have hired a helicopter crew to cut beetle-infested trees on 2,350 acres of rugged terrain along Needles Highway and near Sylvan Lake. Commercial logging was allowed on another 650 acres to help stop the beetles' spread.
  
  

Attraction

• According to South Dakota Division of Resource Conservation and Forestry, park officials have used synthetic forms of the beetles' pheromones to lure them to certain trees or stands of trees, which were then felled.
  
  

Repulsion

• Officials have also used anti-aggregation pheromones to repel the beetles from the limber pine stand at Cathedral Spires, designated a National Natural Landmark by the National Park Service.
  
  

Effects For Visitors

• Some trails have been closed during the anti-beetle campaign, including the Sylvan Lake trail to Harney Peak and the Little Devil's Tower trail, which were closed in late 2009. In addition, timber harvesting has changed the scenery along the Needles Highway.