Occurrence of Fire in Longleaf Pine Southeastern

A healtb.y understory comrmmity is a key factor in maintain@ the biodiversity of longleaf pine (Pinus palustris) Stands, and there 1 appears to be a strong relationship between the occurrence of fire and the condition of the understory vegetauon. Generally, the mulerstory is bakhier in burned areas than in those not burned. TO assess the USC of prescribed 8~ in restoring and maintaining the 1 health of longleaf ecosystems we looked at a subsample of Forest Inventory and Analysis plot data for.longleaf p.me maintained by 1 the U.S. Department of Agric&re, Forest Service. The subsample consisted of longleaf pme plots m Flortda, Georgra. South Carolina, I j and North Carolina. About half of all longleaf pine stands in the Soutbeast had been burned within the last 5 years. Florida had the highest proportion of burned area (58%) and South Carolina the lowest (43%). Although there was some variation among states, fire had been used / , on most public land (83%) but on a relatively small proportion (37%) of privately owned land. In Georgia, where large hunting 1 reserve8 constitute much of’ the private holdings, fire was used on 48% of the privately owned longleaf areas. The use of fire varied by site type and state; lowland areas were burned more in South Carolina, and uplands more in Georgia and North Carolina. There was a strong relationship between burning and understory condition with most of the unburned areas in poor condition. The use of prescribed8re by private owners is not likely to increase as many holdings are small parcels where burning is expensive and ) hifficult. keywords: fire, Florida, Georgia, longleaf pine, North Carolina, Pinus palustris, prescribed burning, restoration, South Carolina, un/ derstory. Citation: Gutcah, K.W. 2000. Occurrence of tire in longleaf pine stands in the southeastern United States. Pages 178-182 in W. Keith Moser and Cynthia E Moser (eds.). Fire and forest ecology: innovative silviculture and vegetation management. Tall Timbers Fine Ecology Conference Proceedings, No. 21. Tall Timbers Research Station, Tallahassee, FL. I N T R O D U C T I O N tingled pine ecosystems once occupied as much as 25 million hectares in the southeastern United State$, extending south from southeast Virginia to central JJIorida and west into eastern Texas (Stout and Marion 1993). Use of this valuable resource began in colonial times, and intensive logging of old-growth longleaf forest reached its peak shortly after the turn of the century (Ware et al. 1993). By 1935, only about 8 million hectares of longleaf pine remained. Once logged, much of the land was converted to agricultural and urban uses-or regenerated with slash (Pinus elZiatii) or loblolly pine (Z? rue&z). Together, these uses contributed to a continual decline in the area of longleaf plant communities. Between 1955 and 1985, longleaf forest area declined from 4.9 million to 1.5 million hectares (Kelly and Bechtold 1990). By 1995, only 1.2 million hectares remained (Outcalt and Sheffield 1996), less than 4,000 hectares of which were old growth (Means 1996). The amount of longleaf ecosystem with an intact understory is not known but is estimated to be OS0.8 million hectares (Noss 1989, Stolzenburg 1991). Longleaf understory is important because it contains most of the ecosystem’s diversity. Not only is the understory plant community very diverse, it also has many endemics that depend on it for survival (Hardin ad w&t 198%. Relatively large, contiguous aea of longled co~utity are needed to maintain viable populations of such species as red-cockaded woodpecker (picoi&,y boreahs). Therefore, resource managers are striving to perpetuate existing understory and restore it on sites where it has been eliminated or severely damaged. prescribed fire is a major tool in ecosystem restoration efforts. Prior to landscape fragmentation brought by human habitation, fire was a frequent, natural occurrence across much of the Southeast and maintained once-extensive longleaf pine and grass communities (Christensen 1981). Dead needles and grass furnished fuel that carried fire and maintained healthy stands (Landers 1991). Without fire, plant community composition and structure changed. Woody species increased, and grasses and forbs declined (Lewis and Harshbarger 1976, Myers 1985). Fire is also known to control brown-spot needle blight (Scirrhia acicolu), which can severely limit the growth and survival of longleaf seedlings (Boyer 1975). Buming encourages the production of flowers and seeds by native grasses and forbs (Christensen 1981, Platt et al. 1988, Clewell 1989, Outcalt 1994). It is therefore necessary that resource managers, conservation groups, and others promote the use of tie to maintain longleaf community health (Landers et al. 1995). Our study objective Was to quantify the occurrence of fire in the longleaf ecosystem by site type, location, and ownerSh@ Such information should help managers concep trate fheir efforts where they are flee&d most,