Gregg Henderson | 7/27/2006 10:40:08 PM
PORT SULPHUR, La. – Scientists from the LSU AgCenter this week started planting grass as the first step in a research project designed to evaluate its ability to protect earthen levees on the Gulf Coast.
The plant, which already is used widely for erosion control and is known to have some repellent qualities to termites, is vetiver grass.
Dr. Gregg Henderson, an LSU AgCenter entomologist and acknowledged expert on termites, this week received his latest grant from the U.S. Department of Agriculture’s Agricultural Research Service. It funds testing vetiver grass against Formosan subterranean termites.
"These experiments are meant to demonstrate that termites will stay away from food sources close to vetiver and are meant to demonstrate their potential for levee plantings," Henderson said.
Vetiver grass is highly tolerant to extreme soil conditions and is often used to rehabilitate contaminated lands. The deep roots anchor the plant and hold soil together on hillsides and contours.
Henderson has been working with vetiver grass for about 13 years and has discovered that the chemical nootkatone, which is present in vetiver roots, repels termites.
He was at the LSU AgCenter’s Citrus Research Station at Port Sulphur, La. Tuesday (July 25) planting vetiver transplants he will use in the study.
Throughout the world, termites have caused problems on levees by tunneling in the soil and weakening the integrity of the structures, Henderson said. He hopes to demonstrate that the vetiver, which is widely known for its effectiveness in erosion and sediment control, will help keep subterranean termites from undermining levees in the United States.
One of the problems with levees in New Orleans has been the infestation of mature trees by Formosan subterranean termites. The termites not only undermine the levees but also feed on the trees, weakening them and contributing to their tendency to topple easily in high winds.
Falling trees that pulled their roots out of the ground are suspected of contributing to the weakening and eventual breaches of levees in New Orleans during Hurricane Katrina in 2005.
Henderson said termites feeding on bagasse seams between the pilings in the New Orleans levees also are suspected of contributing to levee breaches.
"We think vetiver will keep termites out of the levees, but we’re not 100 percent certain," Henderson said. "That’s why we’re undertaking this research."