The Mansionization that has been taking place across Southern California for almost two decades has wiped out significant amount of trees. The increase in a home footprint on a given lot generally wipes about a third of the lots green cover. A USC report estimates that LA County has lost about 55% of its green cover to expanding housing footprints.
“What we saw was lot-line development, sometimes referred to as mansionization. And when there is a larger footprint for a building, there’s more hard-scape, less trees, less grass and shrubs,” said Travis Longcore, a professor of architecture at USC and a co-author of the report.
One might not think this a homeowner losing some shade is a big deal, but on a large scale, the widespread of loss green cover can have significant effect on the environment and our own health. Trees remove carbon dioxide from the air, which contributes to global warming. They filter dust from the air, which can reduce the effects of asthma. Tree roots stabilize hillsides and prevent landslides in periods of heavy rain.
The amount of green cover loss ranges from a high of 55% in Baldwin Park to a low of 14% in tree friendlier cities like Pasadena, Burbank, and Glendale.
Ironically, this loss of trees occurred during the Million Tree’s tree planing initiative launched in 2007 by Los Angeles.