As noted in the photo the East Bay hills were once covered in grasses and oak trees. Now these areas once shown as pristine hills lining the bay are covered in houses with intricate road systems that could easily be congested in the event of a wildfire. These hills now house some of the most expensive real estate in the Bay Area and yet many are still reluctant to deal with the abandoned Eucalyptus groves planted a century ago. Areas such as Claremont Canyon, Leona Canyon and Sibley Volcanic regional Preserve lay in high danger areas where fire can jump from public land to communities. There are many more communities that would suffer if there were a great wildfire like the one that happened in 1991. This area is very dry and prone to very high winds in very dense forested areas with highly flammable fuel sources. These areas contain steep slopes that are hard to get good footing on for firefighting efforts. Living in these areas require extra tasks for each household to maintain low lying branches and specifically cleaning up debris.
In the late 1800’s and early 1900’s investors saw a great opportunity with the U.S. Forest Service voicing their concerns about a looming hardwood shortage. They planted hundreds of trees per acre knowing they would grow four to six feet per year. The timber famine never actually happened and the East Bay was stuck with this abandoned Eucalyptus trees, otherwise known as Tasmanian blue gums grow up over 200 feet tall. They feature sickle-shaped leaves hanging from high branches, and deciduous bark that is peeling from their unshorn trunks. These stands of trees leave such an immense amount of debris they leave up to fifty tons of fuel per acre on the ground. When seasonal winds like the Diablo winds pick up from the east the combination with the oil leafed blue gum trees can produce flames over one hundred feet into the air. The burning embers from the trees can land up to a half mile away from their source increasing the risk to nearby homes. In the 1991 fire it is recounted that the trees just erupted leaving very little or no time for residents to escape the flames.
Many believe this non-native species should be removed from the hills but there are major complications that come with that. If these groves are thinned a bigger problem of the hills turning into a mono culture with a bare understory. Shedding and dying trees will have to be maintenance and water will be hoarded by eucalyptus trees while other species will struggle to grow. This scenario would not promote biodiversity or support many animal species as well. The Eucalyptus trees take a lot of water and prevent sunlight from aiding the understory in growing. The oil that the trees produce prevent other species from flourishing. Native animals and birds will prefer native woodlands rather than Eucalyptus groves. The restoration of the natural landscapes also help provide hospitable environments for native species that are endangered currently like the Alameda Whipsnake and Red Legged Frog.
The University of California successfully removed a sufficient number of trees with the Claremont Canyon Conservancy. Soon after clearing the Eucalyptus groves native trees and shrubs started to grow back. Removing California stands of Tasmanian Blue Gum is a delicate topic and many debate it to the bitter end. There are many ideas on how to manage these trees. This will be more discussed in management policies.