Savannah works to battle insect epidemic while keeping oaks green

<p>Moss-draped live oaks, which comprise the city's lush, green canopy, are being attacked by tiny insects that are turning the trees' leaves a sickly brown.</p><p>City officials noticed the Kermes scale outbreak about four weeks ago, and the suspected culprit is the city's battle against mosquitos. Heavy aerial spraying last year, in response to the West Nile virus scare, killed off small, parasitic wasps that normally feed on the insects.</p><p>"These scale have always been around, but it's more of an epidemic this year," said Savannah Park and Tree Director David White. "I've never heard of it being this bad."</p><p>Kermes scale typically spend their entire life on an oak and limit their feeding to upper branch tips, but in some areas of the city, they have infested large portions of the oaks.</p><p>Such outbreaks rarely kill mature live oaks, though they do stunt tree growth and make branches weak. Saplings are the most susceptible to death.</p><p>"It could be a number of things going on, and that is why we need to be careful not to point fingers," said Elmer Gray, public health specialist for entomology at the University of Georgia.</p><p>Drought-like conditions this spring also could have weakened the trees, making them more susceptible to heavy mosquito spraying.</p><p>A similar outbreak occurred in Southport, N.C., in 1998 when at least half the city's oaks were infested with Kermes scale. Eventually, the city's mosquito-control program was found to be the cause.</p><p>The city cured the trees by using fire hoses to spray the bugs off the leaves, then applying horticultural oil. Southport also targeted where it would spray for mosquitos and cut its pesticide use by a third.</p><p>Chatham County Mosquito Control Director Henry Lewandowski said 2002 and 2003 were busy years for his department. West Nile and equine encephalitis scares were ripe, and heavy rain in March 2003 forced him to order spray flights in Savannah almost everyday.</p><p>Although light rain this year has kept the planes grounded, Lewandowski realizes his department could be the culpable party in the Kermes scale outbreak. He said he is willing to change how his department combats the mosquito problem, and he is exploring the use of horticultural oil on the oaks.</p><p>Gray acknowledged the difficulty of balancing mosquito control and the health of live oaks.</p><p>"If there is a correlation, Henry (Lewandowski) is going to be between a rock and a hard place because if people get sick from West Nile, they are going to look at him," Gray said.</p><p>___</p><p>HASH(0x28667f4)</p>