document: A split , charred tree stump is a clue that lightning was to blame for a forest fire . Carbon particles indicate the exhaust of a passing truck was the culprit . And there are other ways to tell a fire was accidental . `` You eliminate all those causes , you 're down to arson , '' said Dale Smallwood , a criminal investigator for Missouri 's Mark Twain National Forest . He comes down to arson in most of his investigations _ and he and other forest officials believe the problem is often rooted in some regional traditions that are as hard to quell as flames . A psychologist 's study found economic and even aesthetic reasons why some people light woods aflame . Arsonists set 172 of the 296 Mark Twain fires that have broken out so far this year , burning more than 9,000 acres , Smallwood said . A total of 14,200 acres of the forest , which covers 1.5 million acres mostly in southern Missouri , were burned during a spring fire season made more volatile by drought . On average , Smallwood estimates , 70 percent of the forest fires each year in Missouri are deliberately set . `` It 's probably 90 percent higher than the national average , '' said Ron McDonald , Mark Twain 's fire control officer . He said Mark Twain consistently is among the five forest districts with the worst arson problem . `` It 's just been an Ozark tradition of incendiary -LRB- deliberately set -RRB- fires , '' McDonald said . The tradition seems to stretch across the southern United States , according to Smallwood . Fires in other areas are more likely to be caused by lightning or man 's carelessness . As one of the Forest Service 's 125 special law enforcement agents , Smallwood has spent most of the past 16 years investigating fires in the forests he loves . `` I consider myself an Ozark hillbilly , '' he said . The Forest Service is charged with protecting wildlands , and balancing recreational needs with commercial interests in timber and mineral resources . Smallwood 's job includes investigating marijuana growing in the forest , timber theft and theft of other federal property . His military-neat office at the Forest Service headquarters in Rolla is decorated with game bird feathers , a picture of Smokey Bear and a glass-doored bookcase lined with reports and text books . The Forest Service has called on psychologists , sociologists and archaeologists to determine why fires are set . `` Part of it is tradition , '' Smallwood said . `` In the springtime , people used to burn the woods to allow grass to grow . '' A policy of open grazing , with cattle free to feed on any unfenced land , was allowed in the Ozarks until the 1960s , longer than in other wooded areas , Smallwood said . Psychologist John P. Shea in the 1940s conducted one of the first Forest Service studies of arson . Subsistence farmers in the rural South who were interviewed by Shea and his researchers claimed fire helped control ticks , snakes and disease and controlled the encroachment of trees on land where they wanted to graze cattle . `` Their ways are those of frontiersmen living in an arrested frontier , '' Shea wrote . Aesthetics even played a part : Shea and other researchers found that people living in areas where arson was common enjoyed the smell of smoke in the spring air , and believed the woods looked better `` burned clean . '' The Forest Service has attempted to counter the lore that can lead to burning . Over the years , timber has been touted as a cash crop that is as worthy of protection as grassland . Smokey Bear and other programs encourage the view of the forests as a priceless national resource . But the tradition of using fire to manage the woods dies hard . `` There 's no cut-and-dried way to prevent it , '' McDonald said . `` We had one case -LRB- in 1984 -RRB- where two men went to Sunday school and after school they started a fire with their Sunday school literature , '' Smallwood said . `` They just happened to be driving through an area they thought needed to be burned out . '' Still , the arsonist does not always fit the profile of a simply misguided citizen . `` Part of the problem is people driving around drinking and shooting road signs , '' Smallwood said . `` When they get bored with that , they set fires . It 's malicious mischief . `` Sometimes you hear that someone is angry at the Forest Service because of some administrative action _ because we closed a road or disallowed something . And they do n't necessarily have to be mad at the Forest Service . They could be mad at government , period . '' Then , `` fire is used as retaliation . '' `` It 's so senseless , '' he said . `` It just costs a lot of money to put these fires out and it 's coming right out of our tax dollars . '' McDonald , who oversees about 125 Mark Twain employees trained as firefighters , said forest fires cost $ 25 to $ 30 an acre to suppress . In the rare case of a conviction , the arsonist is likely to be put on probation or ordered to pay the costs of fighting the fire and replacing timber that was destroyed , Smallwood said . Last year , a judge ordered two arsonists to work weekends for the Forest Service . `` An arson case in the forest is very hard to make , '' he said . `` When you go out in the middle of the forest to a blackened area to begin an investigation , it 's very difficult and frustrating . No. 1 , you usually do n't have any witnesses . '' He noted that in some cases , people who have evidence withhold it for fear of being burned out themselves . Beyond the cost in dollars of forest fires , there 's risk to those who fight them . `` We had an employee die of a heart attack fighting an arson fire , '' Smallwood said , referring to a 1976 blaze . `` We would have liked to have prosecuted someone in that case . And I would have also liked to have known if the prosecutor would have considered a manslaughter charge against the arsonist . ''
extractive_keyphrases: forest fires criminal investigator investigations passing truck missouri arsonist arson problem