Effects of overstory retention, herbicides, and fertilization on sub-canopy vegetation structure and functional group composition in loblolly pine forests restored to longleaf pine

摘要: The desirable structure of longleaf pine forests, which generally includes a relatively open canopy pines, very few woody stems in the mid-story, and well-developed, herbaceous ground layer, provides critical habitat for flora fauna contributes to ecosystem function. Current efforts restore upland sites dominated by second-growth loblolly require information about how restoration treatments affect sub-canopy vegetation. We established field experiment at Fort Benning Georgia Alabama, USA determine effects four levels approximately uniform density (Control [16 m 2 /ha basal area], MedBA [ 9m LowBA 5m Clearcut [0 area]) three cultural (NT [untreated], H [chemical control vegetation] + F plus fertilization]) on vegetation functional group composition growing seasons following removal. In general, cover (a measure abundance) layer increased with amount was each year. Canopy trees suppressed graminoids first two years after treatment but only Control plots had lower graminoid than third season. Forb significantly season, stems/shrubs or Vegetation year removal, relative dominance groups did not change through time. retention limited development mid-story stems, greatest stem densities plots. herbicide (on both F) reduced 2009, effect no longer significant 2010. Traditional methods converting stands other species commonly include clearcutting followed planting, our results suggest that may release increase will reduce needles fuel bed. Retaining low moderate (5–9 area) provide an effective balance reaching multiple objectives maintaining creating conditions frequent fire regime.