Shade hard to find at most public K-12 schools

Study concludes that many campuses in California are lacking trees and greenery.

- BY TYRONE BEASON

ALESSANDRO OSSOLA, right, a UC Davis urban plant scientist, measures a heat index on a playground.

The vast majority of urban, public grade schools in California are paved-over "nature deserts" sorely lacking in trees or shade — leaving most of the state’s 5.8 million school-age children to bake in the sun during breaks from the classroom as rising global temperatures usher in more dangerous heat waves.

That's the conclusion by a team of California researchers from UCLA, UC Davis and UC Berkeley who studied changes in the tree cover at 7,262 urban public schools across the Golden State from 2018 through 2022.

The ongoing joint project, which drew from urban tree canopy maps developed by study partners the California Department of Forestry and Fire Protection and the U.S. Forest Service, revealed that 85% of the schools lost about 1.8% of tree cover on average in that time span.

The situation appears to be just as worrisome today, the team said.

The researchers also collaborated with the nonprofit Green Schoolyards America, which found in its own 2024 study that California’s public K-12 schoolyards have a median tree cover of just 6.4%. And more than half of that canopy exists only as decoration at school entrances, in parking lots and along campus perimeters.

“Extreme heat is becoming a major public health concern in California and across the country, and trees can play a really big role in helping us cool down those schools and also build climate resilience,” said Kirsten Schwarz, the research lead at UCLA.

Results from the 2018 to 2022 study, which was funded by the U.S. Forest Service, were recently published in the journal Urban Forestry and Urban Greening.