Residents in the Sunset Park neighborhood lamented the loss of four ficus trees in the streets branching inland from the Lincoln Boulevard and Pico Boulevard intersection. A notice was posted on the trees a month in advance, stipulating the intended to remove and/or replace the trees and reasoning for doing so.
“It pains me to lose a single ficus tree, because they are so valuable – they are environmental workhorses.” said Walt Warriner, Community Forester.
The removed-trees suffer from a disease call Nattrassia, a fungal infection, and a related disease, Sooty Canker, which enters the tress through wounds in the roots and/or canopy. There isn’t much known about the two newly-discovered diseases, including all the details on how they are contracted.
The symptoms of these diseases were visible in the canopy (or lack thereof) of the doomed trees prior to their removal. The difference between one healthy tree and one of the infected was like looking at a withered bouquet next to a flourishing bush.
Currently there is no known chemical control for these newly discovered diseases, the notice from Community Maintenance Department said. Even severe pruning of infected parts would have only provided a temporary relief, read the notice, because the pruning wounds would quickly become infected too. The Public Landscape Division said that removal and/or replacement of the giant stressed trees was the best option to avoid spreading the decline to surrounding trees. The notice also sited the danger of leaving structurally damaged trees standing in a residential neighborhood.
Three trees have been or will be removed on the 1000 block of Grant Street. Another tree was already removed from the 800 block of Bay Street, the same block where a tree collapsed in late January, destroying a new-model BMW, due to the softer, super-saturated soil resulting from the downpours of those storms. In fact, the tree recently-removed was next to the one that fell in the storm, leaving that short stretch on the North side of Bay Street lacking a canopy that shadowed there less than two months ago.
These trees in Sunset Park aren’t the only ones suffering. Warriner said as many 20 have already been removed. He points to the spread of the disease as evidence for the “absolute necessity for diversity” in Santa Monica’s urban forest.
“When you have a single species and a pathogen specific to one host, you stand to lose a significant portion of the population,” said Warriner. “The days of single-species trees on a street are passed. Diversity is the best was ensure longevity. “
The good news is that the city will be planting new trees in these areas. The replacement trees will be Catalina Ironwoods on Bay Street and the Sweet Bays on Grant Street. They will be planted as part of the City’s spring 2010 planting program.
Warriner said that the Sweet Bays will grow to the maintained size of the ficuses, but will require significantly less pruning. He also said the Ironwoods, a native plant, is a chance to achieve a more local set of trees.
For questions or concerns contact Warriner or Johnn Aquilla, at Community Forest and Public Landscape Department at 310.458.8974 or firstname.lastname@example.org