Event Website

http://www.nafew2009.org/

Start Date

22-6-2009 2:10 PM

End Date

22-6-2009 2:30 PM

Description

Mixedwood stands of white spruce (Picea glauca [Moench] Voss) and trembling aspen (Populus tremuloides Michx.) are the major forest type in the boreal forests of western Canada. They contribute significantly to Canada’s wood supply and play important ecological services. Bluejoint grass (Calamagrostis canadensis (Michx.) Beauv.) is also a prominent component of boreal mixedwood ecosystems and can impede natural regeneration of white spruce and negatively affect the development of white spruce and aspen mixedwood stands. Several studies have shown that spruce growth declines with increasing aspen abundance. Hence, competition control is often required to achieve acceptable survival and growth of spruce. Resource availability (light, water, nutrients, and temperature) is influenced by the level and type of vegetation control, and at the site level may also modify the competitive interactions. My research is being conducted in connection with a long term study initiated in 2002 to examine the effects of aspen and grass competition and evaluate the selected treatment options. Environmental and tree growth data have been collected over the duration of this study. We will present results relating to: (i) treatment effect on spruce growth, (ii) competition equivalence of woody plants and bluejoint grass on spruce growth (i.e., do they exert the same level of competition), and (iii) temporal changes in competition of woody plants and bluejoint grass on spruce growth (i.e., does competitive equivalence change over time). Results to date indicate that the vegetation control treatments have significant effects on spruce height and diameter growth, woody and herbaceous vegetation differ in their competitive effects, and the relationships between competition and spruce growth are not the same every year due to temporal variation in resource availability.

 
Jun 22nd, 2:10 PM Jun 22nd, 2:30 PM

Competitive Effects and Equivalence of Woody and Herbaceous Vegetation in a Young Boreal Mixedwood Stand

Mixedwood stands of white spruce (Picea glauca [Moench] Voss) and trembling aspen (Populus tremuloides Michx.) are the major forest type in the boreal forests of western Canada. They contribute significantly to Canada’s wood supply and play important ecological services. Bluejoint grass (Calamagrostis canadensis (Michx.) Beauv.) is also a prominent component of boreal mixedwood ecosystems and can impede natural regeneration of white spruce and negatively affect the development of white spruce and aspen mixedwood stands. Several studies have shown that spruce growth declines with increasing aspen abundance. Hence, competition control is often required to achieve acceptable survival and growth of spruce. Resource availability (light, water, nutrients, and temperature) is influenced by the level and type of vegetation control, and at the site level may also modify the competitive interactions. My research is being conducted in connection with a long term study initiated in 2002 to examine the effects of aspen and grass competition and evaluate the selected treatment options. Environmental and tree growth data have been collected over the duration of this study. We will present results relating to: (i) treatment effect on spruce growth, (ii) competition equivalence of woody plants and bluejoint grass on spruce growth (i.e., do they exert the same level of competition), and (iii) temporal changes in competition of woody plants and bluejoint grass on spruce growth (i.e., does competitive equivalence change over time). Results to date indicate that the vegetation control treatments have significant effects on spruce height and diameter growth, woody and herbaceous vegetation differ in their competitive effects, and the relationships between competition and spruce growth are not the same every year due to temporal variation in resource availability.

http://digitalcommons.usu.edu/nafecology/sessions/adaptive_ecology/3