In the 'Urban Forest' of San Jose there are many street trees, many problems; San Jose, CA

In the 'Urban Forest' of San Jose there are many street trees, many problems - San Jose Mercury News: The two sycamore trees stand like faithful old sentries in the middle of a quiet block on East Mission Street, near San Jose's Bernal Park, and at first glance they appear to be identical. Probably planted at the same time, they are about the same size and have a similar wintry grandeur even unadorned by leaves.
But one of these trees is in trouble — as are many trees in San Jose's urban forest. This one could someday become a danger to the neighborhood, and to Christian Bonner, an arborist at San Jose nonprofit Our City Forest, the difference could not be more obvious.
One of the trees has been 'topped,' a now discredited method of pruning that has opened the tree to decay, and possible ruin. Bonner suspects the tree's owner isn't even aware that it's in peril.