The Southern Pine Beetle

Many of you already know that the Southern Pine Beetle is the reason for all of the dead pine trees around here. But do you know why this native beetle killed so many trees? Will it strike again? What else is on the horizon?

The Southern Pine Beetle (Dendroctonus Frontalis) has co-existed with pine trees for hundreds of years without causing the destruction that you can see today as you drive around Fairfield Glade and much of Eastern Tennessee. Normally the little brown or black beetle, the size of a grain of rice, causes little damage. In fact, before the latest attack in the years 1999 through 2002, you have to go clear back to 1976 to find significant pine beetle damage in Tennessee. Also many of the dead pines around here were 60 years old or more. How did they evade the beetle for so long?

It was one of those perfect storms. Southern Pine Beetles normally only cause problems to damaged or stressed trees. Healthy trees either ward off or survive pine beetles. But late summer droughts and severe winter snow and ice in 1998 and 1999 put extra stress on many trees. Plus, large, densely planted pine plantations under stress conditions were a pine beetle paradise. Pine beetle populations are cyclic and they usually peak in Tennessee about every 10-12 years. Everything came together for a Southern Pine Beetle extravaganza… stressed trees, large plots of trees, and a beetle population peak. The result is the thousands of dead pines that you see today. Most dead pines have already fallen, and I don’t recommend hanging out next to any that are still standing in a windstorm.

The types of pine trees affected most by pine beetles are Southern Yellow Pines such as Loblolly, Shortleaf, Virginia, and Pitch pines….precisely the type that we have around here. White Pines are also here but they were less affected because they produce more resin to fight off the beetles.

Will it happen again? Yes it will, but it might be some time before pines die in such numbers as they did in 1999 through 2002. Healthy trees can usually co-exist with the beetles unless conditions all come together like they did a few years ago. It is just one of those natural things.

But there are other problems on the horizon. You can expect major losses of several different kinds of trees in the near future. Here is a short description of just a few of the things coming your way.

The Woolly Adelgid (pronounced a-DEL-jid) is a tiny aphid-like insect that is killing Hemlock trees. It is especially a problem in the Smoky Mountains where some Hemlocks are 150 feet tall and 500 years old. Near Newfound Gap you can see whole hillsides of dying Hemlocks. There is hope that an imported beetle will control the Adelgid just like it does in Asia.

The Emerald Ash Borer has wiped out 20 million Ash Trees in Michigan, Ohio, Indiana and Pennsylvania. It is headed in this direction.

I lived in Pennsylvania when the Gypsy Moths first hit there. Complete hillsides were stripped of all leaves by the voracious Gypsy Moth caterpillars. A walk in the woods sounded like rain from the droppings of thousands of caterpillars. These imports especially like Oak trees…just like the ones in FFG. Estimates are that they will be here in big numbers in 5-10 years. However, once the initial onslaught is over the moths and trees co-exist in better balance.

One story that is showing promise concerns the American Chestnut tree. An Asian bark fungus almost completely wiped out the American Chestnut which used to comprise 25% of the Southern Appalachian forests. But, after 60 years with virtually no American Chestnut trees, researchers have developed blight resistant trees that are just about ready to replant.

Nature is a never ending evolutionary battle. The relationship of the Southern Pine Beetle with its host trees is just one of the more visible results. If history is an indication, the beetles and the pines will continue to co-exist. The woods are already full of small pines filling in the spaces left by their parents.