Invited commentary by John Hitchen, retired East Bay Regional Park District Supervisor. The original version of this article appeared in Berkeleyside, an independent online news site, September 8, 2015
Eucalyptus trees are magnificent and picturesque, but they are inherently dangerous and invasive, depriving native plants of the chance to thrive wherever they grow.
In some cases, exotic plants can co-exist with natives, but, in the case of blue gum eucalyptus, this is not the case. The species has evolved in the extraordinarily harsh, dry climate of Australia to grow and spread quickly to then be burned to ashes in catastrophic wildfires.
According to Jared Farmer, in his recent book “Trees in Paradise,” the moist cool climate of the Bay Area allows the blue gums to re-seed and spread to an extent rarely found elsewhere on Earth.
The Berkeley hills were once primarily grassland and chaparral with native trees along the riparian corridors. Eucalyptus planting was encouraged by a combination of state forestry officials and a number of get-rich-quick entrepreneurs who quickly found that the “miracle trees” had no economic value and were growing so fast that they would actually become a liability to property owners. Ironically, the EastBay Regional Park District’s original acquisitions were purchased at extremely low cost from EBMUD, whose managers foresaw the runaway cost of maintaining eucalyptus plantations.
Unless we are willing to see our human habitat wiped out repeatedly by firestorms fueled by these powerful but dangerous trees, and our native vegetation overcome by them, regaining some measure of control over their spread is essential.
The FEMA project for the East Bay hills is simply another small step towards discovering just how we humans and our California native plants may peacefully co-exist with these incredibly powerful giant trees. The Sierra Club should be commended for their support for eucalyptus management including carefully applied herbicides. (See the article on their website published on Aug. 13, 2015.) The Sierra Club does not take a position on how to treat the stumps, but the proven safe and effective material is Garlon 4 Ultra, which is NOT manufactured by Monsanto, is not a glyphosate, and is not sprayed, but rather dripped or brushed onto the cambium layer of the cut stump.
Doing nothing about our hill area eucalyptus problem guarantees progressively more catastrophic firestorms and soaring maintenance costs. It guarantees that eucalyptus will become the dominant species in our beloved East Bay hills, to the detriment of our native redwoods, oaks, bay trees, toyons, ceanothus, and other indigenous species.
I urge everyone to take a close look at the plant community under a eucalyptus grove, and see the potential for something much more stable and diverse than eucalyptus woodland.