Event Website

http://www.nafew2009.org/

Start Date

25-6-2009 9:20 AM

End Date

25-6-2009 9:40 AM

Description

Long-term demonstration projects on experimental forests can be adapted from their original goals to provide insights into contemporary research questions. For instance, a 32.4-hectare cutover parcel on the Crossett Experimental Forest, the eventual Reynolds Research Natural Area (RRNA), was reserved in 1936 to act as a control for more intensively managed study areas. Over the last 70+ years, the RRNA has been allow to develop under 'natural' conditions that include no harvesting or other human interventions-with the notable exception of fire control. From 1937 until the most recent measurement in 2007, overall stand basal increased from about 20 to 36 m2/ha. The shade-intolerant loblolly and shortleaf pines in this stand remained relatively constant at two-thirds of total basal area until the mid-1990s, after which they declined noticeably, dropping to just over 50% by 2007. The gradual development of a continuous hardwood, shrub, and liana under- and midstory, coupled with a thick litter layer, has severely suppressed pine regeneration. This long-term project has demonstrated that without intense large-scale disturbance events, perpetuating a significant pine component in mesic old-growth sites of the Upper West Gulf Coastal Plain is highly unlikely. Rather, a strategy that incorporates controlled burns and/or deliberate interventions such as underplanting pine seedlings or the release of well-established pine saplings may provide better opportunities for improving pine representation. This is not the only lesson that the long-term study of the RRNA has provided. The gradual transition from pine to hardwood may not dramatically influence carbon storage in mature, closed canopy stands-our data show an aboveground biomass increase of ~10% during the last two decades, even as pine stocking has declined and overall basal area remains largely unchanged. From a sequestration perspective, the conversion to hardwoods, with their denser wood and larger crowns, has more than offset the loss of pine.

 
Jun 25th, 9:20 AM Jun 25th, 9:40 AM

Overstory Dynamics in an Uncut Pine-Hardwood Stand: Lessons From Seventy Years of Passive Management

Long-term demonstration projects on experimental forests can be adapted from their original goals to provide insights into contemporary research questions. For instance, a 32.4-hectare cutover parcel on the Crossett Experimental Forest, the eventual Reynolds Research Natural Area (RRNA), was reserved in 1936 to act as a control for more intensively managed study areas. Over the last 70+ years, the RRNA has been allow to develop under 'natural' conditions that include no harvesting or other human interventions-with the notable exception of fire control. From 1937 until the most recent measurement in 2007, overall stand basal increased from about 20 to 36 m2/ha. The shade-intolerant loblolly and shortleaf pines in this stand remained relatively constant at two-thirds of total basal area until the mid-1990s, after which they declined noticeably, dropping to just over 50% by 2007. The gradual development of a continuous hardwood, shrub, and liana under- and midstory, coupled with a thick litter layer, has severely suppressed pine regeneration. This long-term project has demonstrated that without intense large-scale disturbance events, perpetuating a significant pine component in mesic old-growth sites of the Upper West Gulf Coastal Plain is highly unlikely. Rather, a strategy that incorporates controlled burns and/or deliberate interventions such as underplanting pine seedlings or the release of well-established pine saplings may provide better opportunities for improving pine representation. This is not the only lesson that the long-term study of the RRNA has provided. The gradual transition from pine to hardwood may not dramatically influence carbon storage in mature, closed canopy stands-our data show an aboveground biomass increase of ~10% during the last two decades, even as pine stocking has declined and overall basal area remains largely unchanged. From a sequestration perspective, the conversion to hardwoods, with their denser wood and larger crowns, has more than offset the loss of pine.

http://digitalcommons.usu.edu/nafecology/sessions/longterm/5