In the natural world, once you start to see a thing, you cannot stop seeing it. I first realized this fact as a child, while learning to forage for chanterelles in the East Bay hills. At the time, I called it “mushroom eye,” referring to how anything bright orange in the woods would immediately snap my attention to it, even while traveling at 35 mph on country roads.

“Mushroom eye” is a positive attribute. Unfortunately, the same visual attribute can apply to invasive species, such as the ever-present yellow blooms of French broom or aggressive seedlings of Douglas fir. While zigzagging down country roads, I find my thoughts constantly distracted by invasive species.

At this point, you might be thinking Douglas fir trees are native, not invasive. True, they are native, and I can admire a lovely stand of mature, large fir trees. Yet they are often referred to as the “bully of the woods” for aggressively edging out other native plant communities.

As fate would have it, I am putting my “invasive species eye” to use in my role as a prescribed fire specialist for our Fire Forward program. In recent weeks, I've been working with our stewardship crews at Bouverie, Martin Griffin and Modini Preserves to identify, thin-out and pile-burn small, Douglas firs that stand to threaten beautiful heritage oaks on our preserves.



Small meadow, Martin Griffin Preserve, before



Small meadow, Martin Griffin Preserve, after



Jared Childress assessing young Doug fir for thinning, Modini Mayacamas Preserves



After thinning Douglas fir from this area, the oak woodland will benefit from reduced competition for light and water


Historically, the use of prescribed fire by Native American peoples accomplished this goal—keeping oak woodlands healthy and fire-sensitive Douglas fir seedlings at bay. Currently, the region's deficit of “good fire” has flipped this scenario, allowing Douglas fir to thrive by out-competing the oaks. Being shade-tolerant, Douglas fir trees can exceed the height of light-dependent oaks and suck up limited available water, leaving oak trees susceptible to stressors such as pathogens and drought. This has led to a loss of plant and wildlife diversity—oaks are a keystone habitat for cavity-nesting birds and their acorns are a staple food source—while also creating ladder fuels that increase wildfire severity.

With these thinning efforts, ACR’s Fire Forward is helping ensure a future for our oak woodlands.



Pile burns of Douglas fir along the Cayon Trail of Bouverie Preserve.