Tree equity


The Los Angeles community Sherman Oaks sounds like a place that should be verdant and laden with leafy trees. Not surprisingly, the students of Arbol University found that to be exactly true.

Yet the students, who were using trigonometry and other tools to collect data about Los Angeles’s urban tree canopy, were shocked at the disparity they found between the different neighborhoods they surveyed.

In Koreatown, a lower income community, the tree canopy was not only thinner, but the trees were much younger and more likely to be sick or affected by pests. Damaged sidewalks and other infrastructure problems also threatened the health of the trees there. And the obvious visual discrepancy between Sherman Oaks and the sparse vegetation of Koreatown raised questions in the students’ minds.

Los Angeles' Koreatown has fewer trees than wealthier neighborhoods. Photo courtesy Marc Dadigan.

“They were walking around in Sherman Oaks and seeing all these trees that were 60 to 100 years old, and they wondered, ‘How come this neighborhood has so many trees and others don’t?”” said Miguel Luna, a community organizer who created Arbol University through a National Science Foundation grant.

An urban forest might seem incongruous, but there are currently numerous efforts in cities across the country to thicken tree canopies, and in doing so, reduce pollution, improve public health and even lower crime rates.

None are more ambitious than Los Angeles’s Million Tree Initiative, a multi-year, collaborative effort that seeks to transform a city known more for its smog than its woodlands.

As a starting point, scientists conducting an urban forest analysis to help identify so-called “tree-poor” neighborhoods and formulate a plan for planting and sustaining new trees.

Not surprisingly, the data revealed that Los Angeles’ “tree-poor” neighborhoods also tended to be its financially poor neighborhoods, a correlation that’s well-depicted in these maps.  In greater Los Angeles, tree canopies range from 3 percent in downtown to more than 50 percent in Bel Air-Beverly Crest.

It’s a common theme around the country, from Milwaukee to Washington D.C.: Poorer communities are less likely to have trees while richer communities not only have them but are often named after them.

L.A.’s Million Tree Initiative has targeted tree-poor communities as part of its effort, and Luna believes the additional data that Arbol University collected will help spread the tree wealth.

There are some caveats. For example, the satellite data isn’t very detailed, sometimes mistaking bushes for trees, Luna said. When Arbol University students went into the field, though, they measured not only the physical nature of the trees (its trunk diameter, the size of its crown, etc.) but other information such as the age of the tree and the amount of trash nearby that Luna says will add a social context to the data.

The importance of urban tree cover is becoming better known, with a growing number of studies documenting the economic value of urban trees.  In an era of increasing income disparity as well as health disparity, the uneven distribution of urban trees seems to be contributing these economic and wellness gaps.

According to California ReLeaf, street trees in Portland, Ore., increased the sale prices of houses by $8,870 and add $45 million to the city’s property values compared to the $4.5 million spent on maintaining the trees. There is also the obvious environmental value as the L.A. initiative estimates an additional 1 million trees would consume more than 1.27 tons of carbon dioxide in the next 35 years.

Yet, perhaps even more vitally, the tree canopies can affect the collective mental and physical well-being of a community. Most recently, a study by a renowned urban forest researcher found a link between high tree densities and a reduced risk for low-birth weight babies.

It’s a connection that needs more research to support it entirely, but it’s also a tantalizing hint of the importance of trees and nature in our social fabric. Do they not only have the ability to conserve energy but also the ability to heal?

Bristlecone pine image courtesy Flickr user Marshal Hedin.

During one of Arbol University’s excursions, one of the students asked what tree was the oldest in the world, Luna said. Inspired by that question, Luna rewarded his students at the end of the program by taking them to visit the Ancient Bristlecone Pine Forest in eastern California, home to trees that are literally thousands of years old.

“It was exciting for the students to be walking around those ancient trees, especially since their neighborhoods only have very young trees,” Luna said. “It just gave them a better appreciation for trees and life, in general.”

Marc Dadigan is a freelance journalist based in Redding, California. He's currently living with the Winnemem Wintu tribe and writing a book about their spiritually guide salmon restoration project.

Essays in the Just West blog are not written by High Country News. The authors are solely responsible for the content.