LOS ANGELES — Homeowners who live on the border of El Sereno and South Pasadena are suing to stop the development of new homes on a hillside which they believe will endanger protected trees.

Micah Haserjian and Brenda Contreras’ home is on the border. Orange County-based developer Planet Home Living was given a permit to build a wall five feet from their home. The wall will divide their home and a private road that will lead to the new houses on the hill.

The City of South Pasadena granted the developer the necessary permits to build the street because it's within the city — but the homes are in Los Angeles.

"With the current design, we are connecting to Lowell Avenue so that all of the traffic goes into the city of LA and does not go through the city of South Pasadena," said an engineer who spoke on behalf of Planet Home Living during a presentation to the City of Pasadena.

Haserjian and Contreras have many environmental concerns, including how many native trees will be cut.

“The Southern California black walnut is rare and it’s threatened, and at the rate developers are cutting this down, it’s going to be endangered pretty soon,” Contreras said.

The trees in the hillside behind their home are threatened just as many others are in hillside developments across the Southland. Trees are being cut and not properly replaced, argued environmental scientist Dr. Travis Longcore, science director at The Urban Wildlands Group and a UCLA professor who has data from the City of LA.

“Some of our colleagues looked at the permits that had been issued over the last three years and discovered that the city is actually approving the removal of a mature walnut tree once every week on average,” said Longcore. “Some of these projects in the hills northeast of downtown are approved that average is going to go up rather dramatically.”

Local leaders have written letters of concern about the project. LA City Councilman Kevin De Leon wrote that his "concerns center around potential piecemealing of environmental impacts," for example. LA County Supervisor Hilda Solis, meanwhile, wrote she was concerned about the El Sereno community that has already felt the effects of gentrification.  

Planet Home Living and the City of South Pasadena did not respond to Spectrum News 1’s requests for comment.

The homeowners, who run a land conservation nonprofit, don’t want to see more of these trees gone. They’ve filed a lawsuit claiming the developer was improperly exempted from providing an environmental review required under the California Environmental Quality Act.

“This is what the developer was not expecting, for someone to stand up and fight for what looks like a meaningless piece of land,” Contreras said. “It’s not meaningless. It’s critical.”

Contreras and Haserjian estimate the lawsuit will cost up to $50,000. They’ve started a GoFundMe page to help.