City of Encinitas Tree Tracker

Encinitas has been grappling for years with a proposed addition to its 2017 tree ordinance: mature trees. 

The city already has a category for heritage trees, reserved for trees that are among the oldest and largest of a unique species, have historical significance, or help define a neighborhood. In January 2023, the ordinance was amended to allow the designation of a “heritage grove” — entire groupings of such trees. 

But what, exactly, is a mature tree?

How many of these would be protected as mature trees?

Around the state, cities that do consider mature trees in ordinances describe them as oaks, native oaks, trees of a certain diameter (which varies widely), or any tree close to its full height and crown size.

At the April 24 city council meeting, planners finally presented their recommendations to establish objective standards for preserving mature trees, but there is more work to be done. The first step, defining them, is still proving elusive.

Evan Jedynak, senior planner, explained that "mature tree" would mean any tree with an 11-inch or greater trunk diameter, measured at 4.5 feet from the ground. It would include native species with a 9-inch or greater trunk diameter: coast live oak, Engelmann oak, Fremont cottonwood, western sycamore, and Torrey pine.

According to resident Mark Wisniewski, a certified arborist, the definition fails to account for the growth rates of different species. "Not all species will come to 9 inches at 54 inches above grade, including a lot of the trees we're currently planting," he said. "You've got fast growing trees, slow growing trees, very slow growing trees."

Tree Equity map

And what about the scrub oaks the city was named for? They wouldn't be protected either, he said, "although the urban forest advisory committee is working on a small tree protection ordinance." Encinitas means "little oak."

The city's most important trees, Wisniewski said, "are not being protected by this ordinance."

Jedynak said some trees would not fall into the category of mature trees, regardless of size – trees the city and county define as invasive; fruit trees of any kind; and all palm trees.

The ordinance protecting mature trees would apply to all public property and rights of way, as well as private property with new subdivisions, multifamily housing, and commercial or mixed-use projects. It would affect some redeveloped private property. Single-family properties on single lots, including those with accessory dwelling units, would be exempt. So would all properties in very high fire hazard zones, which officials said are mainly within Olivenhain.

Where developers propose to remove mature trees, the ordinance would require a 3:1 on-site replacement ratio; a 2:1 ratio if native species are used; and a 4:1 ratio for offsite replacement.

Studies have found that about 50 percent of a tree’s wood is carbon, so bigger, older trees are powerful carbon sinks (they absorb more carbon than they release), making their protection an important part of a city's climate action plan. 

A county report notes that trees around buildings can reduce air conditioning needs by 30 percent and save 20-50 percent in energy used for heating. 

Tom Cozens, a real estate agent, argued that drought was at odds with the city's tree planting priorities. "Let's preserve tropical rainforests. You can get an acre for $5," he said. "Encinitas already has a lot of canopy."

In fact, many areas of San Diego have far less. When it comes to "tree equity" in San Diego, Encinitas scores a high 89, while National City, which appears on a map of areas most in need of tree canopy, gets a locality score of 63. 

At the end of 2022, the Encinitas urban forest included 21,806 trees in the public right of way and parks.