The best time to plant a tree

There's a pair of tree wells near me that I've decided represent the tenuous state of Los Angeles's urban forest. In early 2019, the mature, healthy Ficus microcarpa planted here were cut down because their roots had lifted the sidewalk panels. A cathedral-like double canopy of waxy green leaves that layered the sidewalk with dense shade was reduced to two dusty squares in a sea of unblemished concrete. On a sunny day, the new sidewalk and the adjacent stucco wall of a busy medical center generate a white-hot glare blinding pedestrians as they move along a major bus corridor. They had been the only street trees on the entire block.

The city of LA was planning to cut down 12,000 more mature trees just like this until a judge ruled in favor of advocates who had sued the city, demanding that LA make a new plan for preserving trees when repairing its sidewalks. (Residents also sued the city because LA didn't repair its sidewalks.) It wasn't a big deal to cut down mature trees, the city argued, because they would just plant new ones in their place. But the tree wells I kept tabs on gave me a window into how well that worked. First came a pair of purple orchid trees that shriveled up within months, then gold medallion trees that lasted less than a year, and, finally, pink trumpet trees that, thanks to our historic wet winters, survived. I think they're gonna make it, you guys. The whole process from alive tree to alive tree took almost five years.

In 2019, the same year the ficuses got the axe, the city of LA set a goal to plant 90,000 trees by 2021, including "a promise to boost city tree canopy by at least 50 percent in low-income areas by 2028." How are we doing on that? A 2023 report by the Controller's office found the city was still 20,000 trees short of its goal. But when you look look closely at the report, you'll see that only 19,851 of the trees planted were new street trees. The remaining 47,966 trees were given away to residents and community groups to plant on private property — which sounds like these trees will mostly be cooling down homeowners who have permission to dig up their own yards. That's good, in the aggregate, but it's not very helpful for hot sidewalk-users waiting for a late bus.

Interestingly, the city's recent tree inventory — the first since the 1990s — still shows my two favorite tree wells as vacant, which I assume is a point-in-time count that caught them in their empty states. But it makes me worried about our tree data in general. It seems easy enough for the city's forestry department to update the inventory when a new tree is planted, so why aren't we doing that? Does the city count the two rounds of trees that died as "trees planted" towards that 90,000 goal? And how do we track the canopy increase of "50 percent in low-income areas" by the time the Olympics start? When I look at the data for my neighborhood council (search for yours here) we've got a very long way to go: 22.5 percent of the tree wells are vacant, 2.2 percent are stumps, and 15.6 are palms (which don't create a canopy). We're looking at neighborhoods where 40 percent of the existing tree wells currently provide no shade at all.

More trees would help LA avoid the grim future outlined by Edith de Guzman, a UCLA Luskin Center for Innovation water policy expert and co-founder of the Los Angeles Urban Cooling Collaborative, in her introduction to the panel "Cooling Strategies for an Active LA in a Warming World" at the UCLA Luskin Summit this week. Some of LA's most tree-deprived neighborhoods are likely to experience 60 to 90 additional days per year where temperatures reach 95 degrees or more. And LA's residents are simply not physiologically capable of enduring that kind of heat for an extended period of time, said de Guzman. "Even if you're an Olympic athlete."

Onstage with de Guzman was Becky Dale, LA28's VP of sustainability, and as the discussion progressed, I grew more and more worried about the prospect of moving 10 million ticketholders around the region without cars during what could, in all likelihood, be a 17-day heatwave. During the Q&A, urban planner Cecilia Estolano posed the question everyone in attendance was wondering: "Does LA28 plan to make a legacy tree-planting commitment?" she asked. "Say yes."

Dale didn't say yes, exactly. She said that LA28 had formed a sustainability task force (members listed here) which, notably, includes three organizations represented onstage with her: UCLA, Climate Resolve, and the LA Mayor's office. They would certainly discuss it at their first task force meeting, she said. Which would be held in 2025.

"The best time to plant a tree is today," Estolano called from the audience.

If this has you dreaming about filling an empty tree well on your block, I'm sorry to say that requests for new street trees are currently paused, which points to the immense urban greening challenges that the city is facing. Should LA28 take this on, there's a lot more that goes into planting trees than just "planting trees." A true LA28 legacy commitment would not just front the cost for tens of thousands of trees — including gold medallions, of course — it would also pay to water them until 2028 at least to avoid a similar rotating-cast-of-saplings situation that I witnessed. And even if all LA's vacant tree wells were filled, we still need even more trees on public property — particularly along transit corridors — and less pavement. But starting today could provide a bit of respite for Olympic ticketholders making their way to the diving finals on a sweltering July afternoon — and someone waiting at the same bus stop trying to get to work. 🔥