BENEFITING: ROCKY MOUNTAIN BIRD OBSERVATORY
Aspen stands are some of the most biologically diverse, energy-packed, fire-resistant ecosystems in Colorado. They are currently fading out across the landscape. Jefferson Conservation District is already working to open up the forest, bathing the stands in the sunlight they need to regenerate. Without additional aid, however, pressure from elk browse prevents the establishment of new growth. Funds from this effort will go directly towards purchasing elk fence that will stand for 3-5 years to help the aspen get a head start. Five thousand dollars will purchase two miles of elk fence, which can be used as many as three times over. Help us paint the mountains yellow!
The Rocky Mountain Bird Observatory recognizes that many birds, such as the red-naped sapsucker and Lewis's woodpecker depend on aspen stands for food. Aspen promote a dense understory of grasses, forbs, and shrubs that attract a host of wildlife, making them oases of biodiversity in a conifer-dominated ecological desert. What attracts birds, bugs, and plants also attracts mammals such as deer and elk. They use the aspen like desert nomads use an oasis, stopping off to replenish their stores in their journey across the landscape. The fewer the aspen, though, and the more numerous the grazers, the less likely new aspen will be able to reestablish before being nipped off as young shoots. That's where the fencing comes in - holding off the bulk of the grazing until the most delicate tips of the aspen are out of reach.
Even without grazing pressure, aspen oases do not last forever in the Front Range. The same filtered sunlight that makes them good establishment sites for grasses and shrubs also enables pines and Douglas-fir to gain a foothold in their understory. Eventually, these conifers overtop and shade out the aspen. So it remains until disturbance (wildfire, insect outbreak, windthrow, avalanche) opens up the canopy again. The energy storage capacity of aspen roots can buffer a natural cycle of sun and shade, but a lack of disturbance for too long can compromise even the aspen’s ability to fill a new opening. With no green leaves in the sun, the roots slowly use up their energy staying alive, with no replenishment from photosynthesis.
Many of the disturbances that used to naturally promote aspen across the landscape are now incompatible with the advancement of human development into the forest. Recent wildfires have cost not only property but also lives with their unpredictable and destructive forces. Native insect outbreaks have killed off trees within millions of acres, turning them first bright orange, then gray. While both of these disturbances have occurred naturally for thousands of years in Colorado, they produce effects outside the tolerability of human values. Mechanical treatment is part of an effort to promote effective, attractive disturbance within the developed areas of the forest. Forest treatment initially promotes aspen by creating disturbance; fencing from this fundraiser will complete the job by enabling its establishment.
Shepperd, Wayne D. Aspen ecology and management: The foundation for planning into the future. Society of American Foresters, 2008.