RANDOLPH, N.H. (AP) – A series of warm winters featuring late freezes and early thaws have extended “mud season,” hurting loggers in the North Woods.

Randolph contracted in 2004 with MeadWestvaco Corp., which owned paper mills in Maine, to sell wood from the first harvest of the town forest. But the harvest had to be postponed because the logger was unable to finish a previous job.

In 2005, a private capital firm bought MeadWestvaco’s mills and coated paper division, which became NewPage Corp. NewPage hired logger Forest Hicks of Jefferson, who was only able to complete 40 percent of the Randolph Town Forest job by February 2006.

This winter, the ground froze later than last season, delaying logging again. Town forester Walt Wintturri had hoped Hicks could complete the job this year, but said the soil is turning to mud by afternoon. Only one skidder is still able to work, and only in the mornings after an overnight freeze, he said.

Meanwhile, snow melt is filling seasonal streams and creating seasonal wetlands that further inhibit logging because of the potential for water quality violations.

The problem is expected to get worse. According to a recent study by Innovative Natural Resource Solutions LLC, based on conservative estimates of global warming, mud season will increase an average of 10 days over the next century.

That could result in a direct loss to the forest industry of $1.9 billion over the next 100 years, and direct and indirect losses to the state’s economy of $5.6 billion. The study also looked at higher estimates of the rate of global warming and concluded the results would be serious.

“A more dramatic increase in the length of mud season by 60 days over the next century, a loss of roughly 20 percent of the current logging season, could result in direct economic loss to the New Hampshire forest industry of $11.5 billion over the next century and total economic loss to New Hampshire (directly and indirectly) of $33.9 billion,” the study found.