document: Thousands more acres of brush and timber went up in smoke Saturday in seven states in the West , threatening homes in some places , and firefighters contended with wind and high temperatures . `` As the day heats up , you 'll get these reburns going out and the trees dry out and they 'll torch , '' said Forest Service spokesman Ed Christian in Wyoming . `` We hope Mother Nature cooperates with us , '' said Mary Plumb of the federal Bureau of Land Management in Utah . Record highs included 97 at Cheyenne , Wyo. , and 100 at Denver , while Casper , Wyo. , tied its record of 100 . That was Denver 's fifth consecutive day at 100 degrees or higher . Fire crews were at work in Utah , Wyoming , Colorado , New Mexico , Arizona , California and Washington . Elsewhere , four big fires burned in interior Alaska , one having charred an estimated 24,000 acres . A fire in Georgia 's Okefenoke swamp that burned 500 acres of habitat for an endangered species of woodpecker was reported contained Saturday . The Boise Interagency Fire Center in Idaho , which coordinates federal firefighting efforts , listed 7,000 to 7,500 people on the fire lines , along with 42 air tankers , 14 guide planes and 10 helicopters , spokesman Arnold Hartigan said Saturday . So far this fire season , the agency has had 31,000 fires reported , which have burned 1,117,000 acres . In the same period last year , it had 54,000 fires but 765,000 acres burned . The fact that there are more acres burned this year , but fewer fires , `` means this year 's fires are in very rugged , inaccessible terrain , which makes them hard to fight , '' said Hartigan . `` Also , some of them are in areas where there have not been any fires for years , and that means there is excellent fuel available . '' The largest fire in the Lower 48 states was the week-old Diamond Peak fire in Utah , which had burned 12,200 acres of forest and brush in an area 20 miles west of the Utah-Colorado border , just north of Interstate 70 . It was 80 percent contained , but after a week of temperatures around 100 degrees , the National Weather Service predicted possible dry lightning storms and gusting wind . Elsewhere in Utah , the Uinta Canyon fire had burned 3,850 acres 20 miles north of Roosevelt in the Ashley National Forest . Forest Service spokeswoman Cece Stewart said three helicopters scattered incendiary bombs made of chemically treated plastic balls on an unburned 200-acre area between fire lines and the main fire in an effort to stop the fire 's advance . High wind also was expected in northern California , where a 2,500-acre fire near Janesville on the eastern slopes of the Sierra Nevada destroyed two mobile homes . U.S. 395 between Milford and Janesville was closed . `` The wind was pretty brisk . It just blew the fire and pushed it out , '' said Forest Service spokesman Dave Reider . Relentless winds first pushed the fire north , then south , prompting Sheriff Ron Jarrel to order the evacuation of a sparsely populated area about a mile south of the fire line , Reider said . It was unknown how many people were affected . Spokesman Larry Lathrop said a helicopter battling the fire crashed Saturday about four miles southeast of Janesville . Lathrop said the pilot walked away from the crash , but the helicopter was destroyed . The chopper apparently was making a water drop when it crashed . In the Sierra foothills near Oroville , north of Sacramento , a 750-acre fire was contained Saturday after burning four homes , six outbuildings and six vehicles , and forcing about 150 residents to flee briefly Friday night , according to the California Department of Forestry . Firefighters gained the upper hand on a trio of forest fires in Colorado 's drought-stricken mountains Saturday , but a new blaze of an estimated 3,000 acres in grass and timber on the eastern plains had crews scrambling to protect a subdivision in Elbert County . Residents of nine homes in the subdivision about 25 miles northeast of Kiowa were evacuated Friday night , but later were allowed to return home . In the Bridger-Teton National Forest in western Wyoming , a fire had grown to 3,420 acres , burning an additional 1,000 acres in 24 hours , according to forest officials . Forest spokesman Ed Christian said the fire was about 50 percent contained by Saturday night and that with some cooperation from the weather , crews should be able to complete their containment line by Monday . Officials in Arizona gave priority to the Marijilda fire , which had blackened 2,500 acres of forest on the north side of Mount Graham near Safford , and the Chiva fire east of Tucson , which had burned 8,300 acres in the Rincon Mountains , according to BLM spokesman Wendell Peacock . Arizona 's largest fire until Saturday , in the Peloncillo Mountains south of Duncan , along the Arizona-New Mexico border , had charred 8,000 acres but was 80 percent contained . Firefighters spent an eighth day Saturday battling the lightning-caused , 8,139-acre Divide fire 50 miles northeast of Silver City in the Gila National Forest in southwestern New Mexico , U.S. Forest Service officials said . Firefighters in north-central Washington encircled a 4,500-acre range fire early Saturday .
extractive_keyphrases: forest fires firefighters fire crews fire lines fire season federal firefighting efforts