A huge number of Southern California's urban trees are being assaulted and killed by insects and diseases, which is not being stopped right now. The biological nightmare is so worse that person traveling in the region of Southern California can only see dead and about to die liquidambars, oleanders or olive.

As Los Angeles Times cited, among all the Southern California's urban trees, sycamores, plums, oleanders, avocados, Japanese maples, liquidambars, and olive are the most damaged by the insects or diseases. Apart from these trees, Southern magnolias, pink trumpets, pines, and pepper are among those which can be considered as winners, as they are less affected by the insects or pests.

The treescape of Los Angeles needs to be reconstructed. The surrounding communities including the Southern California's urban trees should be reconstructed in order to overcome with the deadly influence of these invasive insects, pests, and diseases on these trees. In terms of a solution, local and state governments have begun to make a list of stronger and less vulnerable trees which could replace the dead ones.

According to Phys.org, planting of new trees was stopped in the year 2008, due to the budget cuts of Los Angeles Bureau of Street Services, which is responsible for trees in the city. The Southern California's urban trees, which are dead and decayed are also not removed due to the limiting of the services of the Los Angeles Bureau of Street Services.

There are approx. 27 million Southern California's urban trees, which are at a risk of infestation. A research conducted by a fellow research forester from the U.S. Forest Service, Greg McPherson, shows the total cost of removing and replacing these 27 million trees which are at a threat of destruction. As per the research report, the cost would exceed $36 billion for removal of dead and ravaged trees.