University of Delaware
delware environmental institute

NSF: A tree stands in the Sierra Nevada

NSF: A tree stands in the Sierra Nevada

White fir, ponderosa pine, Jeffrey pine. Sugar pine, incense cedar, red fir: These are conifers of the headwater ecosystems of California's Sierra Nevada.  If trees could talk, what tales they might tell of the health of the forests, of the winter snows that fall on their branches and of how much water they transpire to the atmosphere.

Now one tree may be poised to do just that, or at least to offer new insights into a place called the critical zone: the region where rock meets life between the top of the forest canopy and the base of weathered rock.  The Critical Zone Tree, this white fir is called. 

It's a scientific totem pole that stands tall in the forest of the Southern Sierra Critical Zone Observatory (CZO).  The Southern Sierra CZO is one of six such observatories supported by the National Science Foundation (NSF). Scientists there recently found that winter snow from Sierra blizzards foretells how much water will be at the base of the mountains during the summer.

This is important for people downstream who toil in California's multi-billion-dollar agricultural industry and depend on water from Sierra snowmelt. That water is the source of more than 60 percent of California's supply.  In addition, without torrents of melting snow cascading across hillsides, wildflowers won't bloom, and the birds and bees that need the flowers' nectar can't thrive.  But more and more, the rivers are running dry, running late or running early.