For all of us fortunate enough to call the Napa Valley home, its apparent that the beauty of our surrounding hillsides is very important to us. It’s also a very important reason visitors return to our famous wine-growing region.
We all realize that open space, forests and the natural environment we cherish moves us emotionally and provides that much needed rhythm of life. Did you know that Napa County has the highest density of oak woodlands in all of California? Not the most oaks, because we are small geographically, but the highest concentration.
The oak woodlands provide that much needed connectivity with our eco-system and natural beauty, and free of charge, they provide two-thirds of the water running down into the valley floor, they aid in cooling our climate and provide homes for thousands of species important for biodiversity. Most importantly, is that the oak woodlands combat climate change right here at home.
Although written specifically about blue oaks, Professor David Stahle, University of Arkansas writes: “In a state famous for remarkable forests, the blue oak woodlands must be included among the most exceptional. Blue oak woodlands are a mosaic of forest and savanna on the foothills of the Coast Ranges and Sierra Nevada, encircling the Central Valley of California.
“These beautiful woodlands are one of the largest ecosystems in California, but they are imperiled by agricultural development, suburbanization and by the apparent decline in natural regeneration.
“Many of the remaining blue oak woodlands were never systematically logged and still contain canopy-dominant individuals that are 150 to over 600 years old. In fact, that remaining blue oak woodlands may be one of the most extensive old-growth forest types left in California. These ancient woodlands contribute to watershed protection and preserve an important component of the eroding biodiversity of California.”
The California Wildlife Foundation/California Oaks proudly state that the window that blue oaks provide into California’s hydrological history offers a roadmap for stewardship as the climate warms.
The annual growth rings of blue oaks record the history of California’s rainfall, because the trees are an integral part of the watershed.
Oak litter, duff, downed logs, understory and root systems stabilize and enrich soil, regulate run-off, prevent erosion, cool riparian corridors and access groundwater and soil moisture. It is estimated that California’s oak woodlands protect the quality of greater than two-thirds of California’s drinking water supply. Keeping our old-growth oak forests standing is essential to achieving a secure water future.
The persistence of California’s old-growth oak ecosystems through prior climate shifts offers a degree of certainty during uncertain times. In addition to their importance to watersheds, oak ecosystem services include the maintenance of biodiversity and carbon sequestration.
Blue oak ecosystems sequester an estimated 18,783,312 metric tons of above and below ground carbon in live and dead trees. In total, California oak ecosystems are estimated to sequester 675 million metric tons of carbon stored. Soil organic carbon is positively correlated with woody plant cover, and can be quickly degraded and lost upon the removal of oaks.
Enhanced and continued protection of all our oak woodlands is paramount here in Napa. We have the opportunity here in Napa County, to set an example for the world to follow. Preservation of our oaks is not mutually exclusive of the need to manage our forests. Let’s do both and help sustain the movement needed to combat our climate crisis.