The Relation of Fire to Stand Composition of Longleaf Pine Forests

Forest fires are more common in the region of the longleaf pine, Pi1nn1s palustris Mill., than in any other portion of the United States. Their frequent occurrence is definitely known to date back for several centuries, as attested by William Bartram ('28) and other early explorers, who reported that fires were often set by hunting parties of Indians in an attempt to corral game. During more recent times, fires have probably been even more numerous than previously. For many years naval-stores operators have intentionally set fire to the woods after hoeing away all inflammable material from the bases of trees being worked for resin. Since each pine tree is protected from the flames by an individually hoed firebreak, the trees usually escape serious stem injury during these fires, and the forest is largely protected against subsequent accidental fires which might destroy valuable naval-stores equipment. In addition to naval-stores operators, cattle owners also have been responsible for a large number of fires, which are set in winter to stimulate the production of early spring forage in the pine woods. Lastly, many of the native populace intentionally burn the woods to remove the heavy accumulation of " rough" 2 a habit passed down within the family for generations. Until recent years, because of the frequent occurrence of fires in the region, probably 90 per cent of the longleaf pine type burned over at least once every 3 to 4 years. It is extremely doubtful if a single acre of longleaf pine timber has ever grown to maturity without having been exposed to fire at least once. In spite of the numerous fires, however, throughout the region there occur vast stands of second-growth longleaf pine. Widespread observations by foresters and numerous scientific field experiments have shown conclusively that longleaf pine, even when in the seedling state, tolerates fire to a degree unequalled by any other indigenous tree species. Pine species associated with longleaf pine are all much less tolerant of fires, especially during the juvenile stages; and it is doubtless to this difference in tolerance of fire that the thousands of acres of pure longleaf pine owe their existence. During the past 10 years a great change has taken place in the south with respect to woods fires. With the development of region-wide interest in