The Problem

Across California, 10,000+ public schools serve 5.8+ million K-12 students on 131,000+ acres of public land, every day. Much of that land is paved and lacks tree canopy in places children spend their time during the school day, so millions of students are exposed to unhealthy high temperatures on a regular basis. These harsh conditions are widespread and amplify the impacts of the climate crisis on children. This is an environmental justice problem with significant impact on school campuses that serve communities of color and in communities with the lowest incomes.

We invite you to explore our California Schoolyard Tree Canopy Equity Map to understand more about the schools in your community and across the state. We encourage you to read our policy brief entitled, California Students Need Trees at School, and the overview below for more information and key findings.

Research LINKS

Research Summary Part 1
(coming soon!)

Approach

Our research team mapped the existing extent and distribution of tree canopy at K-12 public school campuses across California using GIS. Unlike other studies that only assess tree canopy across entire properties, this analysis specifically focused at the sub-parcel level, on the portion of each campus that children use during the school day. We refer to these areas as “student zones.”

Our unique student zone GIS data layer allowed us to compare the amount and distribution of shade on the property as a whole, with the amount of tree canopy available to children in the student zone. We also combined this spatial research with school-level data, including enrollment and demographics, to understand how many children lack shade at each campus.

Figure 1: The conceptual model above illustrates our study areas.

California’s K-12 public school campuses have extremely low levels of tree canopy in places students are present during the school day.

Urban forestry and climate experts recommend that cities plant enough trees to shade 30% of every neighborhood. The California Schoolyard Forest System℠ also seeks to plant enough trees by 2030 that, when mature, will cover at least 30% of the student zones on each campus. 

Our research shows that California’s school grounds only have 6.4% median tree canopy coverage in student zones. This is very far from the goal.

Figure 2: The California elementary school above has 5.0% tree canopy across the entire property (outlined in yellow), but only 1.9% of the “student zone” (shown in light blue) is shaded by trees.

Less than half (45%) of the tree canopy on California’s K-12 public school properties is accessible to students during the school day.

The rest of the tree canopy (55%) is located outside the student zone, in exterior ornamental areas such as school entrances, parking lots, and along the property’s perimeter.

This planting pattern invests precious irrigation water and maintenance dollars in places that don’t directly benefit children or protect their health.

Figure 3: California’s school grounds have more trees for ornamental purposes than are used to shade children during the school day.

Millions of California’s K-12 public school students need more shade at school.

More than 2,597,000 students attend school with less than 5% tree canopy in the student zones. This includes over 1,500,000 students who qualify for Free and Reduced Price Meals.

Almost all of California’s K-12 public school students go to school on campuses with vastly inadequate levels of shade.

Figure 4: The graph above shows the number of students present on campuses with varying levels of tree canopy—and illustrates how far California is from the goal of 30% tree canopy.

Explore the map

Green Schoolyards America collaborated with GreenInfo Network and Bevin Ashenmiller, PhD to create an interactive GIS map that shows the existing level and distribution of student zone tree canopy at each K-12 public school campus in California.

Red dots on the map indicate campuses with the lowest levels of student zone tree canopy (0%-5%). Dark green dots have the highest tree canopy levels (above 30%) and meet the long-term goal set by the California Schoolyard Forest System℠.

Campuses marked with a red diamond have ≤5% tree canopy in student zones AND ≥70% students who qualify for free/reduced-priced meals. These campuses are labeled “Highest Need” on the map.

We encourage you to explore the map to understand the tree canopy levels in your community and across the state. Click on each dot to view a pop-up with more detailed information about the school(s) and tree canopy onsite.

Figure 5: Click on the button (left) to explore the interactive map.

Policy Recommendations

Our California Tree Canopy Equity Study provides valuable information for policy makers and advocates across California. The recommendations in the policy brief, linked below, draw on the key findings from this study as well as previous research, and are designed to help inform policy change that will improve the tree canopy equity problems identified across the state.

For more information about systemic challenges and opportunities to increase tree canopy equity, please read our report entitled, “Taking Schoolyard Forest to Scale.”