Article by Lorie Hammond - 

As you walk Yolo County’s tree-lined streets, parks, and bike paths, you might take them for granted, with no notion of how they got there or are maintained. The purpose of this article is to laud the work of Tree Davis, a non-profit organization whose members have worked for thirty-three years to plant trees, maintain young trees, and above all educate Davis and other Yolo County communities about the importance of trees. The newly appointed executive director of this organization is Yael Franco, an ISA Certified Arborist.

The work done by Tree Davis is becoming even more urgent as Yolo County begins to experience climate change. During an interview I had with Tree Davis Board President Ann Daniel, she explained, “We recognize that climate change is here, and there are some things we can do locally so that we don’t feel so helpless in the face of it… It has been demonstrated time and time again that a green school, shaded streets, and bike paths contribute to better community health, both mental and physical.” 

What does Tree Davis do to help Yolo County citizens prepare for climate change? And what can we as Yolo gardeners do in our yards and public spaces to forward this effort?

Climate-ready education: Based on a grant funded by Cal Fire, called the Climate-Ready Urban Forestry Education Program, Tree Davis engages high school students in Davis, West Sacramento, Dixon, and Winters in tree planting activities, which educate them about urban forestry and community action. Between 2022-2026, they will have planted 220 trees on or near school campuses. Students are not only helping plant trees, but are also learning the importance of shade in enabling children of all ages to spend time outside in an increasingly hot climate. Through Cool School Yolo, a collaboration with the state of Texas and the city of Woodland tree foundations, Tree Davis is also delivering urban forestry education to students at various grade levels in public schools and planting one thousand trees on nine school campuses in West Sacramento and Woodland. 

Community Canopy: In partnership with the City of Davis Urban Forestry Division, Tree Davis works to plant two hundred trees in Davis public spaces, including parks and front yards, each year. Tree Davis also stewards these trees for their first five years to ensure their success. Community engagement is an essential part of this work. Tree Davis hosts an Arbor Tree Festival and volunteer tree planting events during the tree planting season between October - March. As Daniel states: “Community tree plantings have proven that young people take ownership of the trees they plant and observe as they grow.”

Climate-ready landscapes and neighborhoods: In Trees for the Twenty-first Century, California ReLeaf states that “Urban forests are critical to a holistic approach of addressing climate change. Compared to trees in wildlands, they often require more resources and funding to plant and maintain. The co-benefits make them well worth the investment, however, and make them vital infrastructure for cities and residents.”

Trees need attention and care, but they transform hot environments into livable outdoor spaces. As our climate gets hotter, effective tree canopies are becoming increasingly important so that people can walk, bike, and enjoy outside time, all of which are essential to community health and well-being. 

The wonderful tree canopy that Davis and other communities now have will age out, and climate change will make it harder for some current species to survive. To combat this, research scientists and community leaders have recently put together Climate-Ready Tree Lists, which take into account climate change over the next forty to fifty years. Creating these lists was a collaboration between CalFire, the UC Davis Arboretum and Public Garden, UC research faculties, UC Agricultural and Natural Resources, the USDA Forest Service, the Redwood Barn Nursery, and Tree Davis. This is essential work because creating a sustainable canopy for our future does not simply mean replanting the trees we have grown historically. Luckily, UC Davis and community organizations like Tree Davis are approaching this challenge proactively. Citizens can find the tree lists at the Climate-Ready Trees website and should consult them before planting trees in home gardens, since conventional wisdom about what to plant in the Central Valley is being drastically altered by climate change.

I was curious about some of the key climate-ready trees that gardeners can plant on their property. While multiple lists can be found at the website listed above, I’d like to share a few examples. Studying the lists made me aware that climate change is not an abstract or futuristic idea. Since trees live a long time, it is now time to plant the trees that will survive the hotter and possibly more variable weather conditions that will exist in our communities in thirty to fifty years.

Climate-ready small, medium, and large drought-tolerant trees are listed, along with guidelines for planting them. The trees listed below are a few examples of trees appropriate to areas with medium to low-intensity public use that meet various criteria for appropriateness, also listed on the website.

Small drought-tolerant trees include species such as pineapple guava, trident maple, California buckeye, common manzanita, weeping bottlebrush, both Oklahoma and western redbud, and desert willow. Many of these small trees are familiar and decorative, and many have flowers that attract pollinators. The desert willow, for example, has beautiful lavender, pink, and rose flowers all summer, which attract hummingbirds and carpenter bees. Most of us are familiar with western redbud, with its glorious magenta spring blooms. It is important to choose trees that match your particular location. For example, the California buckeye has snowy white blossoms which attract butterflies and hummingbirds in spring, but it loses its leaves early, in late summer. A dead-looking, drought-deciduous Buckeye may not be a good choice for your garden.

In choosing medium-sized trees, a reader might notice that different species in familiar genera are better suited to hotter climates than those we might have planted before. For example, many oaks are listed, but drought tolerant species have been added to the list of familiar trees. The lists on the Climate-Ready Trees website provide other important information, such as how tall and wide a tree will become, and what its shape will be. New cultivars, such as the Red Push Pistache, have been developed for success in a future climate. We are fortunate to have local resources such as UC Agriculture and Natural Resources to help us plan. Yolo County is also lucky that Tree Davis works with various cities and schools to help expand and sustain tree canopies in public places.

Large trees require spaces adequate for their canopies, which might exceed fifty feet, but can provide shaded spaces for walking and outdoor activities for many years. Many species of oaks, including valley oaks, blue oaks, and coast live oaks, have provided long-lived and gracious options for outdoor life since Native American times and remain adapted to our future. Other large shade trees include pines, cedars, hackberries, camphor trees, elms, and fruitless mulberry. 

The Climate-Ready Trees website is very comprehensive, providing suggestions not only for drought tolerant trees but also for exotic trees and trees in irrigated spaces. Anyone planting shade trees for the future would do well to consult the website’s lists, in order to match their spaces with factors listed, such as the height and width of the space available, the existing irrigation which might affect it, and more.

If you would like to see an existing climate-ready landscape, Tree Davis has transformed a 1.4-acre park into the Tree Davis Memorial Grove. Community members have dedicated time and money to honor/memorialize loved ones by sponsoring trees for this landscape. The memorial grove is adjacent to the University Retirement Center at 1549 Shasta Drive in West Davis and can be visited at any time.

Even if you have no space to plant trees at your home, you can help Tree Davis plant trees in public spaces all over Yolo County. Check out the Tree Davis website to find out when the next community tree planting is so that you can lend a hand or to host a tree in your front yard. Plantings are scheduled from fall to spring, from October through March each year. The trees you see as you walk or bike will have more meaning if you participate in stewarding them. The more help and donations the people of Yolo County provide, the more extensive our green infrastructure will be, enhancing all of our lives. Consider supporting one of Tree Davis’s projects with a monetary donation or with your time as a volunteer.

Another version of this article previously appeared in the Davis Enterprise.