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How To Spot Beetle Activity

The most obvious symptom of a southern pine beetle infestation is the discoloration of the needles in the tree's crown.  They will fade from green to dull green, yellowish, and finally reddish-brown before falling.  This needle fade can be easily seen from the ground or the air.


Crown discoloration is just one sign of beetle intrusion.  As the beetles enter the tree along the entire trunk, small light yellow to white pitch tubes will usually form.  These masses of pitch are about the shape and color of popcorn and similar in size.  In areas where the trees are especially weak, pitch tubes may not be formed.  Instead, a collection of reddish boring dust can be found in the bark crevices or cobwebs along the base of a tree.

       Pitch Tubes                                                    Boring Dust


Two other traces of evidence that the southern pine beetle leaves behind are the winding "S"-shaped egg galleries in the cambium as well a blue-stain fungus that the adult beetles introduce.  Along with the girdling effect of gallery excavation, the fungus contributes to the death of the tree by eventually plugging the water conducting tissues.

                        Pine with blue-stain fungus infection



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