Pine trees that are stressed or weakened are most vulner-able to attack by pine bark beetles. Only the southern pine beetle is known to attack healthy trees. Drought, flooding, disease, or damage from fire, lightening, hail, wind, human activity, and other sources can make a tree susceptible to infestation. Dead trees from which bark beetles have emerged may harbor beneficial insects such as the checkered beetle. If dead trees are no threat to property, humans, or pets, they can be left standing to provide homes for checkered beetles and cavity nesting birds. Removal of infested trees is the surest way to get rid of Ips and southern pine beetles. Other options include complete saturation of the entire tree trunk with a recommended insecticide. Trees can be sprayed standing or after being cut and sectioned on the ground. Live pine beetles under the bark of an infested tree. Blue Stain: Pine beetles introduce a fungus as they bore into the tree that stains the sapwood a blue or grey color. The blue fungus stain from a pine beetle infestation. It is best to prune pine trees when pine beetles are inactive. Pruning trees between November and February is preferred to spring and summer pruning. If pruning can’t be postponed, the pruning wounds should be coated with a tree wound dressing to reduce the possibility of a bark beetle attack. Pine bark beetles live under the bark of pine trees. Adults infest new trees by chewing through the outer bark, leav-ing small round holes in the bark that may ooze pine resin (called “pitch tubes”). Adult pine bark beetles create tun-nels or galleries under the bark where they mate and lay eggs. Trees that still harbor beetles will be characterized by green to yellow needles, tight fitting bark (hard to remove from the tree when struck by a hatchet or ax) and soft gummy pitch tubes. There are exceptions to these and homeowners should seek the advice of a forester to be sure trees are still infested. Pine bark beetles not only kill individual trees, but when conditions are favorable their populations can build up rapidly and cause extensive damage. In outbreak years, their activities can be extremely disruptive to forest management practices aimed at wood and fiber production.
http://www.treefolks.org/wp-content/uploads/012-Pine_Bark_Beetles.pdf http://www.walterreeves.com/insects-and-animals/homeowner-qa-about-pine-beetles/ http://www.walterreeves.com/insects-and-animals/homeowner-qa-about-pine-beetles/ http://tigertreeinc.com/how-to-identify-a-pine-beetle-infestation/ http://www.walterreeves.com/insects-and-animals/homeowner-qa-about-pine-beetles/ http://www.treefolks.org/wp-content/uploads/012-Pine_Bark_Beetles.pdf http://www.walterreeves.com/insects-and-animals/homeowner-qa-about-pine-beetles/ http://www.bugwood.org/factsheets/pbb.html
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