Updating LA’s Tree Rules Could Bring More Shade to Underserved Neighborhoods

A new study by USC Dornsife’s Spatial Sciences Institute and Public Exchange reveals that Los Angeles’ strict and outdated tree planting rules are contributing to urban heat disparities, especially in under-resourced areas like Boyle Heights. These rules, originally created to protect infrastructure and public safety, are now limiting tree growth and widening the city’s “shade gap.” The researchers found that most of these restrictions are not codified in law but exist as internal city guidelines, which could be revised more easily to allow for more trees without compromising safety.

To explore the impact of looser planting regulations, the research team compared tree-planting capacity in Boyle Heights and Studio City. Though both areas share similar physical characteristics, Studio City has significantly more trees. Using mapping software and modeling more flexible guidelines seen in other California cities, the study found that Boyle Heights’ potential tree coverage could increase by 26 percent. However, narrow sidewalks and existing infrastructure still limit the types of trees that can be planted, with fewer large-canopy trees feasible in denser, lower-income neighborhoods.

The study also highlights how even small changes to planting guidelines — such as relaxing spacing around intersections, utility poles, and driveways — can significantly expand tree canopy in constrained areas. Since many of L.A.’s current rules are already widely violated without evident safety issues, researchers argue that updating internal guidelines is both practical and impactful. Still, to fully close the shade gap, broader infrastructure investments — like narrowing roads to create planting space — will be necessary. This research underscores the importance of rethinking urban forestry practices as a strategy for climate resilience and environmental justice.