Five people planting young trees in Houston field
Working to implement climate mitigation strategies, volunteers plant trees along Greens Bayou in Houston as part of the Port of Houston Trees & Riparian Enhancement of Ecosystem Services (PoH TREES) program. Credit: Karla Gorostieta
AGU Fall Meeting 2021

During a team-building outing in the summer of 2018, staff of an environmental nonprofit known as Houston Wilderness sailed down the Port of Houston shipping channel in a tour boat. They started to notice a stark contrast in the landscape.

“You had the big metal oil and gas plants with all the tubes and all this gigantic machinery,” said Deborah January-Bevers, president and CEO of Houston Wilderness. “But then you had all these green spaces right along the water’s edge. Most of them were just junk grass, but we thought, ‘There’s room here for trees.’”

Once their sailing trip concluded, Houston Wilderness staff went right to work. They began searching for support from the port authority and landowners to start planting trees in these unused green spaces. But the team wanted to make sure that the trees they planted would have the biggest possible impact on local climate and health for residents near the shipping channel.

In a new study that will be presented on 15 December at AGU’s Fall Meeting 2021, researchers provide an assessment of native Houston trees and highlight 14 species of “super trees” that have high capacities for sequestering carbon, absorbing floodwater, and filtering pollutants. The presenters hope their study, published online this month in Plants People Planet, can serve as a framework for other tree-planting initiatives.

Houston Wilderness aims to plant a million of these super trees along the industrial shipping channel by 2030 to help address public health and climate change concerns. This is part of Houston’s larger goal to plant 4.6 million trees throughout the city in the next decade in an effort to implement climate mitigation strategies that enhance quality of life.

Finding Room for Trees

The idea for this project, known as the Port of Houston Trees & Riparian Enhancement of Ecosystem Services (PoH TREES) program, originated with the Houston Wilderness staff, but the team partnered with graduate students from Rice University, who spent several months gathering data on native trees. The students ranked the trees by their capacity for carbon sequestration, water absorption, and air pollutant removal.

“Most of our 25-mile stretch overlaps with environmental justice areas. They’re generally the areas with some of the highest heart attack rates, asthma rates, and other health issues.”

At the top of this list were 14 species—including American sycamore, red maple, water oak, and river birch—that could siphon carbon, slurp floodwater, and sift pollutants from the environment. Since 2019, PoH TREES has been planting them by the thousands along the Port of Houston shipping channel.

The areas in Houston that could benefit most from the program’s tree planting are home to marginalized populations who are consistently exposed to higher levels of pollution. “Most of our 25-mile stretch overlaps with environmental justice areas,” January-Bevers said. “They’re generally the areas with some of the highest heart attack rates, asthma rates, and other health issues.”

The team is working closely with the Houston Health Department to look for any changes in health statistics in those areas after the addition of trees, which they expect to improve the area’s air quality and mitigate its urban heat.

Building Local Collaborations

For their initiative to work, the team realized the need to create local collaborations. To ensure communication with stakeholders, including landowners and tree-planting volunteers, Houston Wilderness distributes a personalized planting session chart that describes not only the tree species they planted, but also their projected lifetime effects on greenhouse gases, water, and carbon.

The plantings have brought delight to volunteers and community partners alike. Many people in the area “were so excited when we showed up with the trees,” said Karla Gorostieta, associate manager of Houston Wilderness programming and lead presenter of the new research at AGU’s Fall Meeting. “It makes me feel good because they’re getting trees and helping the environment. And they realize it, too.”

“A lot of these efforts that society will have to make in the future are going to be very locally based and designed around local needs and issues.”

Ronald Amundson, a professor in the Department of Environmental Science, Policy, and Management at the University of California, Berkeley, said there’s great appeal in climate mitigation strategies that make communities more adaptable to the realities of changing climates.

“I think a lot of these efforts that society will have to make in the future are going to be very locally based and designed around local needs and issues,” Amundson said.

Houston Wilderness hopes their research and the PoH TREES program will inspire other organizations to develop similar programs for their localities. While this program has been an organizational feat, the team said it has also been a win for the community, who never knew such a program could improve their area. “You’re coming in and educating people who aren’t against it—they just never really thought about it,” January-Bevers said. “And now they’re ecstatic.”

—Graycen Wheeler (@Graycen Wheeler), Science Writer

Citation: Wheeler, G. (2021), Native super trees could provide climate solutions to Houston, Eos, 102, https://doi.org/10.1029/2021EO210658. Published on 15 December 2021.