Katrina, Rita caused huge forestry disaster, adding to greenhouse gases and inviting exotic species

"New satellite imaging has revealed that hurricanes Katrina and Rita produced the largest single forestry disaster on record in the nation -- an essentially unreported ecological catastrophe that killed or severely damaged about 320 million trees in Mississippi and Louisiana," writes Marc Kaufman of The Washington Post, reporting on a study published today in the journal Science, primarily by researchers at Tulane University in New Orleans.

"The die-off, caused initially by wind and later by weeks-long pooling of stagnant water, was so massive that researchers say it will add significantly to the global greenhouse gas buildup -- ultimately putting as much carbon from dying vegetation into the air as the rest of the nation's forest takes out in a year of photosynthesis," Kaufman writes.

"The downing of so many trees has opened vast and sometimes fragile tracts to several aggressive and fast-growing exotic species that are already squeezing out far more environmentally productive native species. Efforts to limit the damage have been handicapped by the ineffectiveness of a $504 million federal program to help Gulf Coast landowners replant and fight the invasive species."

James Cummins, executive director of Wildlife Mississippi and a board member of the Mississippi Forestry Commission, told Kaufman, "This is the worst environmental disaster in the United States since the Exxon Valdez accident . . . and the greatest forest destruction in modern times." (Read more) For a Los Angeles Times story on the study, by Thomas H. Maugh II and Karen Kaplan, click here.