Sculptured Pine Borer
Would you rather hear this article? Click on the above audio to take a short “Walk In the Woods” at Harmony Hill!
Have you ever walked along the edge of a field, through the woods, or even looked up at the night sky and wished you could capture the beauty you saw before you? There are artists who have been able to take a scene and perfectly present it, sometimes in their own way, that causes us to stare at their work. Whether it’s with a camera, as Ansel Adams so skillfully used, or with a brush, as masters like Matisse put their own interpretation on trees and hillsides, we have always been drawn to the use of light, shadow, colors, and scale to capture nature.
Yet, as much as we admire the talents displayed by these and other artists, nothing can ever compete with Mother Nature when it comes to jaw-dropping and awe-inspiring artistry. During this visit, we’d like to discuss a species that looks as though it would be as at home on the canvas of a Van Gogh painting as it is in a pine forest at Harmony Hill. Even its name points directly to the fact that it looks like a work of art!
True to its name, the Sculptured Pine Borer (Chalcophora virginiensis) proves Mother Nature to be a sculpture and painter. And it looks every bit as though it was designed by loosely swirling and blending paints on a palette, while keeping the insect cryptically colored and hidden in nature. That camouflage is perfect for hiding on the bark of a pine tree, a rock on the ground, or even the charcoal of a recently burned area of the forest. In the right light, it is even possible to see metallic glimmerings on the head, thorax, and elytra of this beetle.
With a name like Sculptured Pine Borer, we know you are wondering if this species is one of THOSE pine beetles! You know, the bad beetles that weaken and even destroy healthy stands of pine trees. Rest easy. This species only shows up on the landscape when trees are quite stressed and most often, when trees are already dead and dying. The Sculptured Pine Borer does not initiate damage or attack healthy trees. Adult beetles don’t cause damage at all, aside from munching on a few pine needles. In one of our photos this week, you’ll notice the remnants of pine needles around the mouth of this adult, meaning it did not wipe its mouth before visiting with us!
It has been our experience to only find them in places where dead and dying wood is present. And sure enough, it is an area exactly like that where we found this individual. As we were surveying a stand of Loblolly Pines that had been recently thinned, we walked over some downed course woody debris and stepped over some stumps of harvested trees. Though the woods were quite clean after a thinning, there were still some limbs that had broken off trees that were removed. It is that dead wood that no doubt attracted the Sculptured Pine Borer we discovered. The decaying of this wood in the healthy pine stand will continue and eventually the beetle will lose a reason to be in this specific location.
But we must remember adult beetles reproduce and make a new generation; grubs that do, in fact, eat the wood of trees. Again, it is important to remember that the adult Sculptured Pine Borers lay their eggs on trees that are dead, dying, or are stressed to that point. They seek out crevices in the bark of pine trees or even wounds or cracks in the tree itself to lay their eggs in.
These grubs are interesting to see in their own right. They have a flattened head that makes them resemble a small hammerhead worm! As they bore into the wood of dead and dying trees, they chew tunnels and crawl through the interior of the trunk and branches. Because of their flattened heads, the tunnels are wider than they are tall; giving the tunnels a shape much like a tiny sideways football.
If you ever split open dead or dying pine wood and see the channels dug by the larvae of Sculptured Pine Borer, you can even observe the growth of the larvae! As the larvae grow and they get bigger, so do the tunnels! If you have a piece of wood with a long enough zig zagging of channels of a Sculptured Pine Borer larva, you can observe the story of the lifespan of the grub by tracing the small tunnels to the wider tunnels!
Eventually, the grubs will chew their way out of the tree just as they become adults. Just as with their feeding channels, look for that oval, sideways football shape in the exit hole!
The question some of you may have might be, “Are we concerned about having this species in the forests of Harmony Hill?” The answer is, “No”. Considering we observed this in a part of the forest where we just had a logging crew do a thinning operation to increase the spacing and health of the trees, a place where we have down course woody debris on the ground and stumps of trees that were removed, we are not worried. This is precisely the sort of habitat we would expect to see Sculptured Pine Borers.
It is something; however, that we will keep watch for, should we experience a severe drought or other situation that could put extreme stress on the pines in those stands. We’ve had pretty good rainfall thus far this year; but, as anyone around here knows, that is something that can quickly change.
In the meantime, we will take a little time to admire the chiseling and brushwork of Mother Nature found on this beetle. The wavy strokes of an unparalleled artist showing her mastery of hues and color matching, hints of metallics, and making a gorgeous beetle that can disappear atop the granite outcrops and pine barks of Harmony Hill.
Before we close out this visit, let’s look at that name. We’ve all been able to appreciate the appropriateness of the common name, Sculptured Pine Borer. But what of the scientific name, Chalcophora virginiensis? Well, the genus name of Chalcophora means bearer of copper and is a direct reference to the metallic iridescence seen on this species in the right light. The species name is an easy one to interpret and is a nod to where this species was first collected and described, Virginia.
A very quick sidenote… A closely related species, Chalcophora georgiana, looks a whole lot like Chalcophora virginiensis. The Southern Sculptured Pine Borer often has a much more pronounced coppery tone on its exoskeleton, while the Sculptured Pine Borer tends to have an overall charcoal coloration dominated by blacks and grays. Though there are variations in the patterns and colors of both species, we feel confident in the identification of this individual, as there was a complete lack of copper and an abundance of gray and black.