Forsythe II Project Mixed Conifer

Greater Spacing has been created between this stand of old ponderosa pine
In mixed conifer stands, trees would be thinned and favor ponderosa pine over other conifer species in order to maintain a more resilient stand to drought and fire.  Thinning the mixed conifer stands and maintaining a combination of individual trees, clumps of trees with intermingled tree crowns, and openings across the landscape will provide for a healthier and more resilient forest while increasing and maintaining habitat for a wider range of wildlife species.   

Mixed Conifer Stands
Mixed conifer stands include a species mix of ponderosa pine, Douglas-fir, limber pine, lodgepole pine, and aspen. Historically, ponderosa pine and mixed conifer stands were characterized by a mosaic pattern of individual trees, clumps of trees with a diverse understory and openings across the landscape. Mixed severity fires, both human and natural caused, created this historic mosaic pattern where clumps or groups of trees were left unburned, understory trees were thinned, and openings were created. Mixed conifer stands in higher elevations were characterized by much lower fire frequency and patches of stand-replacing fire in addition to low-severity surface fires (Evans, Everett, Stephens, and Youtz, 2011). Within the project area, ponderosa pine and mixed conifer stands have departed from historic fire regimes (a pattern of fire occurrences, frequency, size, severity, and fire effects in a given ecosystem) in the era of fire suppression. Generally, mean forest cover rose from 57% prior to settlement to 83% currently, and the current condition of any one location (along the Front Range) is 3.7 times more likely to be forested now than prior to settlement (Dickinson 2014). Because fire has been excluded for decades, many ponderosa pine and mixed conifer forest stands now have interlocking crowns with few canopy openings, become overgrown with understory vegetation, and overall are homogenous rather than multi-age. As a result, these stands are more susceptible to insect and disease epidemics and uncharacteristically intense fire.

Shows tightly space ponderosa stand before thinning
An example of interlocking crowns in a pre-treatment mixed conifer forest. The low branches are evidence that fire has not been in this area in a long time. Fire helps naturally prune ponderosa pine.
     
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