RESTORATION OF A LONGLEAF PINE ECOSYSTEM IN EAST TEXAS

Caldwell, Katherine

Longleaf Ptne (Pinus palustris) ecosystems, among the most species-rich in the temperate zone, once dominated the southeastem coastal plain of the Uniteistates, but now, as a result of fire suppression, land use changes, logging and exotic invasion, less than 3o/o o,f original longleaf communities temain. Restoration programs have been initiated throughout th. ,ri'ti.r. ,"rrg"" to teestablish these ecosystems. Two ptoblems of particular concern are whether recovery of the gound layer can occur naturally and what level of shrub control is required to permit ground layet recovery. These quesdons were addressed at a site in Big Thicket National preserve, Texas where restoration was initiated June 2003 by canopy r.d,i.tion, buming and selective herbiciding. I quantitatively measured species composition of the herb, ,trr,rU, and canopy layers to determine how many desirable species had persisted on the site, whether invasive species were colonizing and whether the shrubs o, .^rropy trees were suppressing herb-layer composition or dchness. Aftet the first growing,""ror,-lir" tree basal area was g.03 + 4.64 mtfha,live tree density wzs 127.1 + 101.2 t."I7h", tall shrubs (>1-) covered 1176 mz/ha (nearly l2o/o)' low shrubs (<1-) coveted approximately 13%, ground layer cover was approximately 25o/o, and the remaining 507o wasbare ground. In all, i'ppro*imately 159 species were fotrnd' with Eupatoium cEillifoliun bSrng the most importanr forL and Diciantheliin spp. being the most abr-urdant gtaminoids. Although diversity "ip.*. to be lower than in mature ISoncgbleiaiaf scitbesli' usenv eral deBsuirlebdo sftoltlrisb sn li(aetz.gfo. lPzait)lo -p.s.ls" grpa.r.u.t"nntfti.ll aS,'oijamtreir aeglgegteansss)i vaen d." gilrya m..i.nr.o..isdssi o(ne.agl. species (e'g' Eupatoriuru c@ilbfo/zum, Andmpogon airginicus, CorJin raiadrn:u) were also pfesent. Woody shrubs did not n-egauve\ impact herb specier. x.,rJrth"less, their rapid recovery and the presence of undesrrable-species suggests ,!* ^ fire regime of frequent, low intensrty fues needs to be condnued in-order to frrlly restore the native r.Jget"tion. Aaditionalty, some manual planting of desired herbs may be necessary to increase herb cover"g" ".ri prevent the colonization of exotic species.

RESTORATION OF A LONGLEAF PINE ECOSYSTEM IN EAST TEXAS

Collections