HELENA -- U.S. Sen. Conrad Burns urged Gov. Brian Schweitzer to declare a fire state of emergency Thursday and activate the Montana Army National Guard for firefighting -- more than a month after Schweitzer had already done so.

In a brief letter faxed to the governor's office Thursday, Burns, a Republican up for re-election in November, expressed his concern for the gravity of the 80,000 acre Derby Fire near Columbus.

"Entire ranches have been consumed and homes have been lost," Burns wrote. "Based on these conditions, I am requesting that you declare a State of Emergency."

Schweitzer declared just such a state of emergency on July 11 -- thus, activating the Montana Army National Guard. He issued a second declaration on Aug. 11.

National Guard helicopters were first deployed to fires on Aug. 3. Guard members showed up Thursday to help on the Derby Fire, said Bob Harrington, the state forester.

Bruce Nelson, Schweitzer's chief of staff, responded to Burns' letter with a brief, faxed letter of his own outlining the steps the governor's office has already taken and including copies of the governor's past emergency declarations.

James Pendleton, a Burns spokesman, said the senator was "pretty sure" Schweitzer had already issued such a disaster declaration, but just wanted to make sure.

"The genesis of the letter was just to make sure that all the bases were covered," Pendleton said. "This is not a political football. It's just a cover-the-bases letter and certainly casts no aspersions on the governor."

Pendleton said he thought Schweitzer, his staff and all the state employees working this year's fire season were doing "an admirable job in a difficult firefighting year."

Schweitzer spent part of Thursday at the Derby Fire.

"Sen. Burns has a lot of important things (he's) doing in Washington, D.C.," he said. "So maybe the things we've already been doing on the fires for the last 45 days, well, it just slipped by him."

Burns drew criticism earlier this summer when he told an elite group of firefighters they had done a "piss-poor job" on a fire. They had been working on a fire near Billings and were gathered at the airport there awaiting a flight to another fire.