TAMPA, Fla. - Critical drought conditions in the Southeast are killing trees, leaving them so brittle their limbs snap or so frail they become easy prey for fungi and insects.
Florida forestry officials estimate drought will affect as many as 4 million trees this year. With normal rainfall, about 1 million trees die of disease and natural causes in the state annually.
The primary culprit is the southern pine beetle, which becomes more active in dry weather and is ravaging trees in Georgia and Florida.
''I'm professionally, totally depressed,'' said Bob Der, of the Hillsborough County Cooperative Extension Service in west-central Florida. ''I've been a forester here for more than 20 years, and I've been in forestry for 34, and I've never seen anything quite this bad.''
Healthy trees can fight infection - sap from a strong trunk can wash beetles away before they bore too deep. Hypoxylon canker, a contagious fungus that eats through bark, can lie dormant inside a tree for years.
''I make my money saving trees and doing sick tree diagnoses, and it breaks my heart to see this,'' said arborist Loren Westenberger. ''The only treatment is a chain saw.''
Forestry officials fear the hordes of beetles will invade healthy trees once they have finished with the weak ones.
''Once they reach that level, it's like a forest fire. They move from tree to tree,'' said Ed Barnard, a forest pathologist with the forestry service.
The unstable, diseased trees pose a danger to houses, power lines and people.
Jack Duncan, a University of Alabama maintenance worker, narrowly escaped a 40-foot limb that snapped off a tree Wednesday.
''I heard a popping noise and knew something was happening,'' Duncan said. ''I just didn't know what direction it was coming from.''
Storms could help relieve the drought but they would create another problem, forestry officials said. Even in less severe storms, the parched trees are likely to drop many branches.
In Baton Rouge, La., a storm in July with 31-mph winds snapped so many trees and branches it looked as if a hurricane had swept through, said Eddie LeBlanc, a tree maintenance company operator.
''Trees are in a critical state,'' said Randy Harris, assistant director of the Baton Rouge city-parish Department of Landscape and Forestry.
Louisiana in general has more old trees than most states, making its forests more vulnerable, said Bonnie Stine, head of the urban forestry program in the state Department of Agriculture and Forestry.
About the only thing landowners can do is aerate the soil, water deeply, have a specialist remove any dead branches, and leave fertilizer alone, she said.
On the Net:
Alabama Forestry Commission: http://www.forestry.state.al.us/
University of Florida Cooperative Extension Service: http://www.ifas.ufl.edu/www/extension/ces.htm
Florida Division of Forestry: http://www.fl-dof.com/
Georgia Forestry Commission: http://www.gfc.state.ga.us/