Recovery of Oak-Saw Palmetto Scrub after Fire

摘要

We sampled previously established permanent line-intercept transects (15 m length) in oak-saw palmetto scrub 6, 12, 18, 24, and 36 months after a fire and recorded cover by taxon in the 0-0.5 m and greater than 0.5 m height layers to determine patterns of recovery. Transects were located in two stands that were seven years (six transects) and 11 years (four transects) since the last fire when burned. Shrubs and herbs recovered by sprouting with little change in species present or species richness. Regrowth of Serenoa repens after burning exceeded that of the oaks; its cover in the greater than 0.5 m layer returned to preburn values within one year. Oak cover (greater than 0.5 m layer) was less than preburn three years after the fire. Differences in growth rates resulted in changes in dominance of mixed oak-saw palmetto transects. We used detrended correspondence analysis ordination to examine resilience after fire. Oak-saw palmetto scrub is very resilient compared to most shrublands. All successional vectors returned toward original locations in fires at 7-11 year intervals. Patterns of recovery varied along the scrub composition gradient. Mixed oak-saw palmetto transects recovered more slowly and showed greater changes in their post-fire composition than saw palmetto-dominated transects three years after burning.