Gardeners, beware burrowing beetle and other pests

VIRGINIA BEACH

Last spring, Ron Eaton noticed what looked like toothpicks sticking out of the trunk of a sasanqua camellia in his yard.

"I was shocked. I had no idea what it was," he said.

Eaton and his wife, Jan, who live along Lake Smith in Virginia Beach, cut off a piece of the trunk and took it to Peter Schultz, director of the Hampton Roads Agricultural Research and Extension Center on Diamond Springs Road.

Schultz, an entomologist, is interested in plant pests that infest nursery trees and shrubs.

"And Pete said, 'Oh, my gosh, I cannot believe you have this thing! I am studying it,' " Jan Eaton recalled.

The "thing" that was adorning the sasanqua with "toothpicks" turned about to be a granulate ambrosia beetle, a scourge of plant nurseries in the mid-Atlantic. It gets its name from the ambrosia fungus it carries on its back to feed its young.

Tiny, reddish-brown and nondescript, the beetle could escape detection in the garden. But the "toothpicks" it leaves behind on trees are hard to miss.

"The insect does not feed on the tree or the cellulose," Schultz said. "They bore into the tree to create a gallery, where the fungus grows and the eggs are laid."

Scientists often call the toothpick-like remnants "frass" - a combination of sawdust that the beetle kicks out as it bores into a tree, and insect waste and sap that hold the sawdust together.

Schultz is working on ways to control the beetle. Once they have infested a nursery tree, the tree can't be sold. The beetles are not particularly picky about where they build their baby galleries. They will choose most any tree, except a conifer.

By observing something unusual and taking their concerns to Schultz, the Eatons did exactly what The Nature Conservancy is urging folks to do: Be observant of trees and forests as you hike and work outside this summer.

The conservation organization wants you to become familiar with the insects and diseases that are threats to trees in the region and report anything unusual, said Faith Campbell, senior policy representative in the Conservancy's Forest Health Program.

"More often than not, the presence of an invasive insect or disease that has spread to a new area of the country has been detected by a concerned member of the public," Campbell said.

Invasive insects are easily moved from one part of the country to another on nursery stock. They also can be shipped in from foreign countries. Sometimes they are found in the wood from which packing pallets are built.

The Nature Conservancy offers two websites that could be helpful in identifying what you see: www.invasivepests.org and www.forestryimages.org.

If you can't identify a new-found insect that is gnawing on your trees, you can photograph it or the damage and send it to your local extension agent or you can take a specimen in to be identified.

As for this area, Schultz suggests that folks also be on the lookout for the emerald ash borer, a shiny green beetle. The emerald ash borer probably arrived in the area on cargo ships from Asia a decade ago. It was found in Virginia several years ago and has already killed millions of ash trees in the Midwest and along the East Coast, including Virginia.

More info elsewhere online: http://www.invasivepests.org and http://www.forestryimages.org

Mary Reid Barrow, barrow1@cox.net