Everglades National Park , Homestead, FL

Long Pine Key plots.  (Site Photographs) Some of the last remaining pineland-rockland communities occur on Long Pine Key in Everglades National Park in southern Florida. These are pine savanna communities with an monospefic overstory of South Florida Slash Pine and a rich understory community. Fire is integral to the persistence of these systems and in the absence of frequent fires, the pinelands are replaced by tropical hardwood hammocks. Pineland-rockland communities face many challenges to their continued existence including altered disturbance regimes and non-native, invasive species such brazilian pepper.

Dr.Bill Platt (Louisiana State University) began establishing eight 4- hectare research plots in 1993 following Hurricane Andrew (August 1992) and subequently expanded the sampling to sixteen plots.    All trees above 1.5m dbh have been completely mapped in these stands with biennual censuses of growth and annual censuses of mortality.  Beginning in January 2001, I assumed primary responsibility for maintaining these plots in close cooperation with Dr. Platt.  I have intensively sampled eight of these sixteen plots, including cone production, seed rain, and seedling dynamics in addition to growth and mortality censuses.  In 2002 and 2003, I established a series of permanent photopoints from which we have begun to photographically document changes in stand structure.

Wade Tract, Thomasville, GA

Tall Timbers Research Station plots. (Site Photographs) The Wade Tract is one of the few remaining old-growth longleaf pine stands.  As such it provides a glimpse into what much of the southeastern United States may have resembled before European settlement. Dr. Bill Platt established a 60-ha research plot in the Wade Tract in 1978.  All trees above 1.5m dbh were tagged and mapped.  In 1979, Mr. Jeptha Wade placed 80 ha of his Arcadia Plantation (i.e., the Wade Tract) into a conservation easement and provided Tall Timbers Research Station (Tallahassee, FL) access to the site. The Wade Tract has been recensused about every four years since then by Dr. Platt and colleagues.  I have been involved in Wade Tract censuses in 2000 and 2003.

The Wade Tract overstory is dominated by longleaf pine.   Some of the longleaf pine are several hundred years old (longleaf pine may live for 500 to 600 years), but the stand structure is mixed with individuals of many different ages.  Longleaf pine basal area is approximately 12 m²/ha with 100-120 stems per ha.  Longleaf pine generally produce a large cone crop (mast) every 9-10 years and longleaf seedlings establish in distinct patches (similar to 'gap' recruitment in closed forests).  Longleaf pine are resistant to fire; longleaf seedlings have a fire-resistant grass stage, in which a thick tuft of needles protects the apical meristem from fire. Older longleaf pine have thick bark that protects the trees from high fire temperatures and shed their lower branches so that fire can not enter into their crowns.  Hardwood tree species are less fire tolerant than longleaf pine and become established in areas with reduced fire frequency. This results in open longleaf savannas with intermixed hardwood stands.

 The Wade Tract is a rich reservoir of species diversity.  The groundlayer is especially diverse with 413 documented plant species.   The groundlayer is dominated by wire grass (Aristida beyrichiana), which plays an important role in structuring the ecological community by carrying fast-moving, cool surface fires through the pinelands.  The endangered red-cockaded woodpecker (Picoides borealis). and gopher tortoise (Gopherus polyphemus) are found on the Wade Tract.

The Wade Tract is burned prescriptively every two years by staff of Tall Timbers Research Station.