Growing a resilient urban forest, Part 1: Species selection
by Stephanie Robinson
February 6, 2023
This is the first article in a series dedicated to sharing our best tips for growing resilient trees that can not only weather intense storms, extreme heat, and drought, but also protect our region from these threats. For over 40 years, the Sacramento Tree Foundation has worked to grow thriving communities through stewardship of our urban forest. In our climate, we depend on trees to make our neighborhoods livable and lovable — but our urban forest also depends on us to help it meet the demands of a changing climate. Here’s our approach, and some tips for residents to grow strong trees today to meet the challenges of tomorrow.
The first step in growing a resilient urban forest is choosing tree species that will thrive in our climate and urban environment with low risk of environmental or safety issues. With over 60,000 tree species worldwide, it can be overwhelming to know which ones will be best for your yard. Fortunately, the Tree Foundation and our regional partners in urban forestry have closely studied trees over many decades and narrowed down the list to a manageable palette of recommended species.
Want our foresters to help you pick trees that will grow well on your property? Sign up for a free siting consultation to get up to 10 free trees for your home or business.
A history of planting in the City of Trees
Until the late 20th century, tree planting choices were largely based on aesthetics and changing fashions. In Sacramento, different trees came in and out of vogue and were often planted in monocultures. From eucalyptus, palms, and elms in the earliest days of our cityhood, fads eventually shifted to Modesto ash, fruitless mulberries, liquidambars, and ornamental pears taking their turns in the spotlight in following decades.
Since these trees were planted for their appearance more than their attributes, they fell out of favor when residents realized their traits were not compatible with our neighborhoods. Susceptibility to pests or disease, intrusive roots, weak branches or structure, and invasive tendencies have stopped these species from being replanted. Unfortunately, those bad experiences also turned some people off from planting trees altogether.
If you have one of these trees in your yard, rest assured that they can still be lovely trees! As long as they are healthy and not causing issues, you can continue to enjoy these trees for a long time even if we wouldn’t recommend planting them today.
Turning a new leaf in species selection
Today, urban forestry takes a more scientific approach. Over the last 40 years, the Tree Foundation has carefully observed which species grow well in our climate and soils without serious disease or structural concerns.
Every summer, we monitor a random sample of trees we planted in previous years to measure growth and note any tree health issues. To identify climate-ready species that can thrive in an increasingly hot and dry environment, we’ve collaborated with the U.S. Forest Service to plant experimental trees and observe their growth over many years. We also draw on the expertise of municipal arborists, owners of tree care companies, nursery growers, and urban forest researchers who sit on our technical advisory committee and share their hands-on experience with the performance of various trees in our region.
All of this data factors into our Shady 80 recommended trees, a list of approximately 80 tree species that are known to grow well in the Sacramento region and foothills. As new research and issues emerge, we reevaluate this list to offer updated recommendations.
What we consider before recommending a tree
Before recommending a species or cultivar, we gather a lot of information and data about the tree. These are some of the questions we ask:
Is the tree suited to an urban environment?
- Does the tree have a strong structure, sturdy branch attachments, and a good ability to compartmentalize decay?
- Can it withstand the stresses of an urban environment, such as air and water pollution, reflected heat from paved surfaces, and compacted soil?
- Does it have a relatively noninvasive but robust root system that will firmly anchor the tree in the soil?
- Is it free of potential hazards or serious nuisances such as heavy falling cones, messy or staining fruit, noxious odors, caustic sap, sharp thorns, poisonous leaves, etc.?
- Is it relatively low maintenance during establishment and once it is mature?
- Will people find it attractive or desirable enough to plant it?
- Is it long-lived?
Is the tree suited to our region?
- Can it withstand our hot and dry summers, occasional winter freezes, and common soil types?
- Is it a low or moderate water user?
- Is the species or genus already over-represented in our urban forest?
- Is it susceptible to pests or disease that could pose a threat in our region?
- Does it offer any habitat value to pollinators or wildlife? Is it native to our region?
- Does it have the potential to be invasive or harmful to local ecosystems?
- Are there mature specimens in the area to observe? How are they performing?
Is the tree suited to the specific planting site?
- How much growing space and soil volume will it need? Is there room for it to comfortably reach its mature size without causing issues?
- Can it thrive with the surrounding soil, irrigation, and sun exposure?
- Does it offer desired benefits such as shade, habitat value, stormwater capture, air filtration, beauty, food, privacy, etc.?
- Do its maintenance requirements match what the property owner wants to provide?
- Are there any children, pets, livestock, or honeybees onsite that could be harmed by ingesting it?
We’ve done the research so you don’t have to
Take the guesswork out of species selection and let our foresters help you pick trees that will thrive in your yard. Thanks to our partnership with SMUD, you can receive a free siting consultation and up to 10 free trees if your property is eligible. So far, Sacramentans have planted over 650,000 trees through this partnership. Together, we are growing a livable and lovable region that is resilient in the face of 21st century challenges.
We understand that some people feel hesitation to plant trees after past bad experiences. However, we hope that more information and transparency can provide some reassurance, and we would love to answer your questions about any concerns you have. Sign up for a free consultation to get site-specific advice from one of our foresters, or call us at 916-924-8733.
Check back for Part 2 of this series to learn more about choosing the right tree for the right place.