MISSISSIPPI STATE -- Mulching is a springtime ritual for many homeowners, but there is concern this year that the common practice could bring unwanted and costly visitors to homes.

During 2005, hurricanes Katrina, Rita and Wilma felled thousands of trees along coastal areas from Texas to Florida. Many of those trees, especially in urban areas, have been shredded for mulch. Because trees are a common habitat for Formosan subterranean termites, there is concern that the pest could be transported in mulch to previously uninfested areas.

Native to China and now established throughout Asia, the Formosan termite is thought to have entered the United States through ports, including those along the Gulf Coast, as stowaways in wooden crates, pallets and other materials. They are more destructive than native termites and have caused millions of dollars in damage along the Gulf Coast in recent years.

There are, however, safeguards in place to prevent movement of potentially infested wood products out of areas where Formosan termites have already been found.

“A quarantine has been in place since 2002 against shipment of any potentially Formosan termite infested wood products out of the 25 Mississippi counties south of I-20,” said Mike Tagert, director of the Mississippi Department of Agriculture and Commerce's Bureau of Plant Industry at Mississippi State University. “No wood products, including mulch, railroad crossties and utility poles, that have been in contact with the ground can be legally shipped out of those counties without being inspected and certified by the Bureau of Plant Industry.”

Shipment of mulch and other wood products out of the hurricane damaged areas of Louisiana also is regulated. The New Orleans area has been a hotbed of Formosan termite activity in recent years, and the possibility that mulch from New Orleans could find its way to Mississippi has alarmed some homeowners.

“We have not had any reports of anyone trying to ship Louisiana mulch into Mississippi or any reports of Formosan termites in mulch from any other origin,” Tagert said. Mulch from hurricane-damaged trees in Mississippi's southern counties, he added, can be used in those counties.

There are precautions homeowners should take when using mulch or any other wood product around their homes, said research entomologist Jianzhong Sun at the MSU Coastal Research and Extension Center in Biloxi.

“Cultural control is an important part of an integrated pest management strategy for subterranean termites,” Sun said. “Recommended cultural control practices include keeping plants away from structures, avoiding placing mulch against structures, keeping chemically treated soil in place, and repairing faulty or leaky plumbing around structures.”

MSU termite research also has shown that certain types of mulches are less attractive to termites.

“Our 2005 research shows that some types of mulch are repellant, distasteful or toxic to subterranean termites,” Sun said. “Our survival data from a mulch nutrition test showed that mulch from certain types of trees, including cedar and melaleuca, contribute to high mortality in Formosan colonies.”

An objective of Sun's research is development of a termite-resistant mulch to prevent the spread of Formosan subterranean termites.

Homeowners with concerns or questions about termites and mulch can contact the Mississippi Bureau of Plant Industry at (888) 257-1285.