Some tree activists in the local community, as well as neighbors who lost a number of large Eucalyptus trees in the past two years, speculate the Eucalyptus are dying from a fungus spread by Shot Hole Borer beetles, accelerated by drought and a very humid summer. Without consulting a licensed arborist it is hard to determine the exact cause of death (more below).*
Photo: Diane Edwardson, October 10, 2014. Neighbors alerted us to trees being cut down on the Red Car Property. On the north end of the property, there were at least 9 dead & dying Eucalyptus in May. Tree contractors appear to only be taking those trees down so far.
The current Eucalyptus die-off started on Adelbert in March 2013 & moved down the Red Car Property toward Riverside Drive. The trees appear to die rapidly once they started to go.
Photo: Diane Edwardson, May 24, 2014. In May, we advised the property owner's rep of the 9 large dead trees. The dead 3 trees in this photo were the small ones.
Without an expert examining these trees & bugs, we don't know exactly what killed them. We advise you to seek expert advice quickly if your trees are starting to die off.
In response to a large, seemingly healthy tree going down near his house last week, one Riverside Place neighbor said, "This seems to be the time of year when big Eucalyptus Trees fall or drop large branches for no apparent reason." It's also a good time of year to trim back your Eucalyptus trees so they don't get blown over in a Santa Ana windstorm, potentially causing property damage or fire.
*UPDATE 10-18-14: One of our neighbors, who is a tree expert, pointed out: "Trees are often hollow in the middle - they are only "alive" in the cambium layer, between the bark and the wood. This is where they actively move water and sap between their roots and leaves. The inner rings/wood is the old cambium from previous years."
I apologize for any confusion this post may have caused. However there is no doubt Eucalyptus trees are dying all over the neighborhood. They are non-native, highly combustible (even when they are alive) & can cause great damage when they fall.