Fire Frequency and the Pine Barrens of New Jersey

Publisher Website
Google Scholar
Abstract
State fire records and literature citations were examined to estimate both regional fire frequency and point fire frequency. The number of annual wildfires in the 550,000 ha Pine Barrens has remained at .apprx. 1100 since 1940 when fire control became effective. The total area burned annually dropped sharply from about 22,000 ha during 1906-1939 to 8,000 ha in the past 4 decades. Extensive wildfires of 8,000-16,000 ha each are common. Since 1838, about every 2 decades on the average, 10% or more of the predominant pine and oak forest burns in a single year (50,000 ha). An average point in the pine and oak forest burns currently at about 65 yr intervals, compared with 20 yr intervals earlier this century. The number of wildfires in the region correlates linearly with the number of dry months in a year. The area burned annually is constant with up to 4 dry mo. during the Jan. to Sept. period; both average and variability of area burned increases with 5 or more dry months. The upland Pine Barrens are a mosaic of fire-caused patches at 2 levels of scale: a fine-grained scale of small (averaging 6 ha) young patches imprinted on a coarse-grained scale of large (several tens of ha), variable-sized patches more than 4 decades old. The drop in point fire frequency favors non fire-adapted populations, hardwoods swamp replacing cedar swamp and loss of the coarse-grained landscape mosaic.