When the California State Assembly passed Assembly Bill (AB) 1573 recently, it created a big potential change to public landscape design and the use of native plants.

Assemblymember Laura Friedman (D-Burbank) introduced the bill that focused on replacing nonfunctional turf with water-conserving California native plants for commercial and public landscaping projects.

AB 1573 is the first bill of its kind to create a requirement for the use of California native plants.

“Landscaping has so much potential to support California’s important goals to conserve water, support biodiversity, and connect more people to nature,” said Assemblymember Friedman, who was a key member of last year’s California delegation to the United Nations Biodiversity Conference (COP 15) and is the author of a companion bill, which would ban the use of potable water for irrigation on nonfunctional turf, AB 1572. “This bill helps unites those important goals, which is why I’m thrilled to see it moving forward.”

The bill focuses on commercial and public works projects. Home landscapes, edible gardens and lawns used for recreation or civic gatherings would not be impacted by the requirements. The legislation uses a phased approach that begins with a 25% requirement for the use of low-water native plants in 2026, working up to 75% by 2035.

“We understand that our industry partners — growers, nurseries and landscapers — need time to prepare and adapt,” Friedman added. “We are committed to working together to ensure this bill is as much practical as it is aspirational.”

The bill’s final requirement for the use of 75% native plants by 2035 reflects a growing understanding of the specialized relationships between native plants, insects and birds. For example, research out of the University of Delaware and the Smithsonian Migratory Bird Center found that populations of chickadees within residential yards required a native plant biomass of at least 70% to sustain their populations. One-third of bird species rely on insects for food, and those insects often depend on very specific native plants to survive. For the birds to have enough insects to eat, native plants must be present to attract those insects.

Advocates say the bill comes at a critical inflection point for biodiversity. Wild vertebrate populations have dropped 69% since 1970, and 1 million species are now at risk of extinction globally. A NatureServe report published earlier this year found that 34% of plants and 40% of animal species in the US are at risk of extinction. California — the state with the greatest diversity of plant species in the nation and home to 40% of North America’s native bee species — also has the highest percentage of at-risk species for native plants and pollinators.

“Biodiversity is in peril, and we all depend on it for our survival,” said ecologist Jun Bando, executive director of the California Native Plant Society, which is sponsoring the bill. “In urban and built environments, there are few large swaths of land still available for conservation, but this bill in combination with efforts like [NRDC] 30×30 helps us stitch together a patchwork of life-giving habitat that really can make a difference. We’re grateful to Assemblymember Friedman for her leadership in seizing this largely untapped opportunity.”

Dozens of organizations, including Metropolitan Water District of Southern California, Save the Bay, Center for Biological Diversity and Defenders of Wildlife have supported the bill, which is not only good for wildlife and plants, but people too.

“Just imagine experiencing fragrant, beautiful plants and pollinators as you walk into your pharmacy, take your kids to school or sit at a traffic stop,” said Bando. “Not all of us have the time or ability to go out on a hike to experience nature. This gives everyone, wherever you are, a chance to make that connection in your daily life.”

The bill has been referred to the Senate Natural Resources and Water Committee for consideration on June 27.