Climate Column: Petaluma harnesses the power of trees
NATASHA JULIANA
ARGUS-COURIER COLUMNIST
August 29, 2024, 5:30PM
My daughter is lucky enough to be the fifth generation to spend time on a small island called Chebeague off the coast of Maine where her great-great-grandmother Janet built a small summer cabin in 1920. Family lore tells us that Janet’s daughter Ann then planted an acorn that became the huge oak that now shades the porch and supports the swing.
As the Greek proverb goes, “A society grows great when old men [or women] plant trees in whose shade they shall never sit.”
And now, more than ever, we need those trees.
When we talk about taking action on climate change, our options usually fall into two buckets: mitigation and adaptation. Mitigation describes all the ways we can reduce or eliminate the change. Adaptation covers everything we can do to adjust to the change.
Burning fossil fuels has already altered the atmosphere so much that 99 percent of Americans have experienced an extreme weather alert since May 1, 2024, as documented by the Union of Concerned Scientists. To mitigate these unnatural disasters, we can stop burning fossil fuels. For example, at home we can switch from gas to electric furnaces, hot water heaters, and cooktops to reduce our emissions.
Or, to adapt to these new unnatural disasters, we can become more resilient. In this case, we might add fireproof roofs and storm shutters in an attempt to protect ourselves from dangerous weather.
When it comes to trees, they fall into both categories.
As a mitigation technique, the forests of the world are vital to planetary stability, miraculously breathing in our overproduction of carbon dioxide and exhaling life-affirming oxygen. A recent TED Talk by climate impact scholar Johan Rockström titled “The tipping points of climate change – and where we stand” brilliantly describes the critical work nature is doing to keep our precious Earth in balance. But when we destroy these ecosystems, they can’t help us anymore.
Forests are one of these key ecosystems that act like shock absorbers for the planet. By halting deforestation and replanting what we have already lost, we can regenerate these important biological systems that reduce the load of carbon dioxide in the atmosphere.
As an adaptation measure, trees provide significant cooling when temperatures soar. Have you ever noticed that sitting under a tree is even more comfortable than sitting under an umbrella? Not only do the leaves provide shade from the sun, but as they breathe, they transpire water droplets into the air that further cool the surroundings. When properly positioned around our buildings, they even help keep the inside cooler by blocking the sun's rays before they can enter, dramatically reducing solar heat gain. And in cities, where we have paved over the soil with asphalt and concrete, trees offer a much-needed respite from the overheated ground.
Locally, we are in the midst of a citywide challenge to increase our canopy by 10,000 trees. ReLeaf Petaluma, with the help of its partner organizations and hundreds of volunteers, has already planted more than 1,600 trees in Petaluma’s parks and schools.
This fall, the effort continues as ReLeaf Petaluma, Cool Petaluma, and the city of Petaluma have teamed up to offer free native trees to Petaluma residents to add to their properties. The city received $1 million from the Inflation Reduction Act and the USDA Forest Service Urban and Community Forestry Program for a tree-planting initiative called the Petaluma Canopy Project, which is funding this exciting new residential tree program.
“If all of us plant native trees, we can make an instant difference, because as the trees grow, they are sinking carbon, making oxygen, cleaning the air, and creating habitat,” explained Carolyn Lacerra of ReLeaf Petaluma.
Why native trees, you might ask. ReLeaf Petaluma was formed to help turn the tide on climate change and biodiversity loss – two intersecting existential crises. When we plant native trees, not only do they suck carbon dioxide from the air and provide natural cooling, but they also add critical habitat for local wildlife, including bees, butterflies and birds.
Evolution has created an intricate web linking all of life. Lacerra explained to me one of these delicate dances, which goes like this: Trees produce chemicals to prevent herbivores from eating them. Local insects evolved to be able to eat native trees but can’t get through the chemical defenses of most non-native species. That might seem like a good thing, but birds can’t feed their babies if they can’t find soft-bodied insects like caterpillars – and those caterpillars can’t survive without their native trees. And, of course, those caterpillars also miraculously turn into butterflies, which act as important pollinators for all kinds of plants, including our food crops.
If you are a bit confused, that’s OK. It just goes to show that nature has a complicated way of making everything work together, and we need to respect that system if we want life to thrive.
If you would like to help make a difference in an instant, you can learn more about this fall’s residential tree-planting program at coolpetaluma.org/canopy-project.
Natasha Juliana is campaign director for Cool Petaluma. She can be reached at natashaj@coolpetaluma.org. For information on how to get involved, visit coolpetaluma.org.