Experts said they expected that most of the lost forestland would never be replanted. Most of the people who lost trees in the hurricane were tree farmers, and replacing the felled trees in the months after the storm was not a high priority.

Farming trees “is hardly ever the only thing a private landowner does,” said Amanda Box, a spokeswoman for the Mississippi Forestry Assn. in Jackson, Mississippi. “I may also have cattle, and I may be a schoolteacher.”

The federal government earmarked $504 million for tree replacement, but the programme typically provides only half the cost of replanting, along with a small stipend — as low as a net of $100 per acre in some areas — to keep the trees growing for a decade.

Owners struggling to rebuild their homes and businesses in the wake of Katrina weren’t able to make up the difference and many sold their land to people who used it for residential construction. Only about $70 million in government funds has been disbursed, and no more than 100,000 acres have been replanted, Cummins said.