John Foltz (352) 392-1901, ext. 130
James Meeker (352) 372-3505
GAINESVILLE—A tree-killing beetle has invaded the Ocala National Forest and by the time its work is done the face of the forest could be drastically changed, say entomologists with the University of Florida and the state Division of Forestry.
Other North Florida private and public woodlands are infested, too. The southern pine beetle has reached outbreak proportions along the Gulf Coast in Levy County, leaving foresters worried about where it might turn up next.
“These are explosive conditions,” said entomologist John Foltz, of UF’s Institute of Food and Agricultural Sciences. “These outbreaks are an 8 or 9 on a scale of 10.”
The southern pine beetle is the most aggressive and destructive bark beetle that feeds on southern pines, Foltz said. Its scientific name, dendroctonus, means “tree killer.”
Entomologist James Meeker of the state Division of Forestry estimates 75 to 100 square miles are infested and that as many as 3,000 acres of pines could be lost this summer in Marion County alone. Anyone with pines along the Oklawaha River has cause to worry, he said.
Trees successfully colonized by the beetles cannot survive, regardless of control measures, like pesticides. The beetles also carry and introduce into trees the deadly blue stain fungi.
The best way to control pine beetles is to cut down trees and treat infested bark at the first sign of infestation. That’s an option that can cause controversy, Foltz and Meeker said, because of the public’s natural tendency to want to preserve trees.
A tree will appear healthy for a short time after pine beetles begins dining on it, making people reluctant to cut it down. By the time the crown turns rust-colored, the pine beetles have moved on to the next tree.
“People get upset about cutting down green trees when, in fact, they’re long dead,” Foltz said. “By the time the crown turns red or brown, it’s too late to save the trees next door.”
In the Ocala National Forest, foresters’ hands are tied, Meeker and Foltz said. Foresters would like to take action to keep the beetles from spreading to healthy trees and neighboring properties. But a lengthy public review period required prior to cutting has delayed any action. Meanwhile, southern pine beetles can kill a tree in just two days.
“The way to maintain the integrity of the forest is to give the forester the option of taking control measures once southern pine beetle is spotted,” Foltz said.
“The southern pine beetle is like cancer,” Foltz said. “We need to detect it early and treat it early by removing the infested trees.”
In the Ocala National Forest, Silver River State Park, the Cross Florida Greenway and private lands, stands of pines dating back to the turn of the century already have succumbed to southern pine beetle. Along State Road 40, the forest corridor through Silver Springs is scenic no more.
“Trees like these, of about 80 years, are old for loblolly pine in Florida, and these were monsters,” Meeker said. “These were just remarkable. Big, big, big. Probably some of the biggest loblolly in the state.”
The outbreak could change the face of the forest, unless the pines are replanted. The remaining hardwoods will be quick to fill in the gaps left by the pines, Meeker said.
The dead pines present another hazard as well, because they could be quickly ignited by a careless camper or by lightning. The resulting fire would be very difficult to fight because of the heavy fuel provided by the fallen and dead trees.
Meeker said most of the pine forests in Florida historically have been slash and longleaf pine. But in the last 30 years, commercial foresters have planted more loblolly pine and the loblolly acreage has more than doubled, he said.
Unfortunately, Meeker said, loblolly is a southern pine beetle’s favorite meal. The voracious beetle, however, will turn to slash and longleaf pine under outbreak conditions, when populations become overwhelming.
“The forests of Florida are good southern pine beetle habitat and under the right conditions an infestation can explode 10- or 20-fold in six weeks,” Foltz said.
“For the foreseeable future, Florida will have southern pine beetle outbreaks and the sooner we detect them and control them, the shorter and less severe the outbreaks will be.”
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