Pine Straw Harvesting , Fire , and Fertilization Affect Understory Vegetation within a Louisiana Longleaf

Pine straw harvesting con provide on economic benefit to landowners, but the practice may also change the composition of plant communities. This research was initiated in o 34-yeor-old stand of longleaf pine (Pinus palustris Mill.} established in 1956 to study how pine straw management practices (fertilization, prescribed fire, and straw harvesting) affected plant communities, and herein, effects on understory vegetation ore reported. A randomized complete block split-plot design was installed with two main plots: (1) no fertilization and (2) fertilization three times with different combinations of N, P, and K. There were four subplot treatments: (l) control, (2} prescribed fire, (3} prescribed fire and 2 harvests of pine straw, and (4) 13 annual harvests of pine straw. Fertilization significantly increased gross cover os o percentage of surface oreo. However, there was o general lock of understory plant response to nutrient amendments, portly because pine straw harvesting and burning were confounding fertilization effects. Prescribed fire and mechanical harvesting activities created similar understories on subplot treatments 2, 3, and 4 by significantly reducing understory woody plant stature and removing litter. Increases in understory tree and shrub stature, number of woody vines per acre, and percentage of woody plant cover significantly decreased herbaceous plant yields and percentage of cover.