Event Website

http://www.nafew2009.org/

Start Date

22-6-2009 10:30 AM

End Date

22-6-2009 10:50 AM

Description

Whitebark pine (Pinus albicaulis), a non-commercial five-needle white pine (Family Pinaceae, Subgenus Strobus), and the only North American stone pine (Subsection Cembrae), inhabits upper subalpine and treeline zones throughout the western United States and Canada. The most northerly in distribution of western North American white pines, it occurs across 18∞ of latitude and 21∞ of longitude, and comprises diverse community types--successional, climax, and treeline, mesic to xeric, and pure to mixed associations. Studies within the last three decades have elucidated a unique ecology for whitebark pine, derived in part from obligate seed dispersal by Clarkís nutcrackers, but also from its multiple functional roles. These roles include facilitating community development after fire, acting as a nurse tree on harsh sites, and protracting snow melt at treeline, thus regulating downstream flows. Whitebark pine seeds are an important wildlife food for granivorous birds and mammals, including black bears and grizzly bears in the Greater Yellowstone Area and elsewhere. Whitebark pine may be considered both a foundation and a keystone species for promoting regional biodiversity, influencing ecosystem processes, and facilitating community development and stability. Furthermore, in some treeline ecosystems, whitebark pine is the most frequent conifer to initiate formation of tree islands, which in turn may facilitate treeline response to climate change. Whitebark pine communities are experiencing dramatic declines as a result of widespread infection by the non-native fungal pathogen Cronartium ribicola, which causes white pine blister rust, advancing succession from fire suppression, and widespread outbreaks of mountain pine beetles (Dendroctonus ponderosae), particularly in the Greater Yellowstone Ecosystem. Furthermore, climate change is predicted to result in range shifts for whitebark pine both to higher elevations and more northern latitudes. As whitebark pine declines as a functional component in subalpine and treeline ecosystems, the resulting structural and functional changes in communities may have multiple effects, particularly on regional biodiversity.

 
Jun 22nd, 10:30 AM Jun 22nd, 10:50 AM

Whitebark Pine as a Foundation and Keystone Species: Functional Roles and Community Interactions

Whitebark pine (Pinus albicaulis), a non-commercial five-needle white pine (Family Pinaceae, Subgenus Strobus), and the only North American stone pine (Subsection Cembrae), inhabits upper subalpine and treeline zones throughout the western United States and Canada. The most northerly in distribution of western North American white pines, it occurs across 18∞ of latitude and 21∞ of longitude, and comprises diverse community types--successional, climax, and treeline, mesic to xeric, and pure to mixed associations. Studies within the last three decades have elucidated a unique ecology for whitebark pine, derived in part from obligate seed dispersal by Clarkís nutcrackers, but also from its multiple functional roles. These roles include facilitating community development after fire, acting as a nurse tree on harsh sites, and protracting snow melt at treeline, thus regulating downstream flows. Whitebark pine seeds are an important wildlife food for granivorous birds and mammals, including black bears and grizzly bears in the Greater Yellowstone Area and elsewhere. Whitebark pine may be considered both a foundation and a keystone species for promoting regional biodiversity, influencing ecosystem processes, and facilitating community development and stability. Furthermore, in some treeline ecosystems, whitebark pine is the most frequent conifer to initiate formation of tree islands, which in turn may facilitate treeline response to climate change. Whitebark pine communities are experiencing dramatic declines as a result of widespread infection by the non-native fungal pathogen Cronartium ribicola, which causes white pine blister rust, advancing succession from fire suppression, and widespread outbreaks of mountain pine beetles (Dendroctonus ponderosae), particularly in the Greater Yellowstone Ecosystem. Furthermore, climate change is predicted to result in range shifts for whitebark pine both to higher elevations and more northern latitudes. As whitebark pine declines as a functional component in subalpine and treeline ecosystems, the resulting structural and functional changes in communities may have multiple effects, particularly on regional biodiversity.

http://digitalcommons.usu.edu/nafecology/sessions/whitebark/1