• Old mountain forests are prime targets for the bark beetle.Jupiterimages/Photos.com/Getty Images
  
  Several species of pine bark beetle are native to North American forests. Although insects and woodpeckers generally keep populations in check, occasional outbreaks can infest millions of trees, according to Colorado State University. The beetles burrow under the bark, where they lay their eggs. When the larvae hatch, they continue to burrow, disrupting the tree's ability to take in nutrients and water. The trees eventually turn brown or red and die. There is no cure for infected trees and treatments focus on prevention.
  
  

Maintain Health

• Pine bark beetles gain the upper hand when trees are stressed by drought, disease, overcrowding or age. To maintain health, water trees deeply for several hours, especially in the fall, according to the Washington State University Extension. Fertilize trees that show signs of nutrient deficiencies, such as slow growth or yellow leaves. Cut down and destroy old or diseased trees to remove potential targets.
  
  

Spray

• As of 2010, no pesticides have been found effective for use in treating already infected trees. Because the insects burrow inside the trees, pesticides won't readily reach them. However, several sprays are effective for preventing infestations when applied to green trees in early summer. These sprays include carbaryl, permethrin and bifenthrin formulations. When using these chemicals, spray the tree from the base of the trunk to the point where the trunk narrows to less than 6 inches, according to Colorado State University. Spray trees on dry, cool days and read the package directions carefully. Stronger solutions of these chemicals are required when treating for pine bark beetles, compared to what you would use for other insects.
  
  

Destroy Infected Trees

• Once trees are infested with pine bark beetles, they must be destroyed to contain the infestation. Dry, dead trees left standing also create a fire hazard. To identify infested trees, look for sawdust at the base of the tree, as well as popcorn-shaped masses on the sides of the tree. Cut down the trees in winter when the insects are dormant. Burn the trees, peel the bark back or put the trees through a chipper. If you choose to save the wood for firewood, wrap it in plastic, and place it in a sunny location for two or three weeks to destroy the beetles.