Right Tree (Species Selection)
A unique advantage of developing a new neighborhood is being able to pick the tree species for the neighborhood before homes are built, roads are paved, and the permanent infrastructure is installed. Initially, it removes the two major conflicts one typically faces in selecting trees for a site: (1) space in the ground (sidewalks, water lines, driveways), and (2) space in the air (electrical lines, buildings). Without these restrictions, one has the freedom to pick the trees for a neighborhood based on the characteristics you desire, and then design a neighborhood that allows trees to grow to maturity while avoiding conflicts with infrastructure. It is an opportunity to choose the defining look and feel of the neighborhood and it’s streets, whether it be trees with magnificent spring flowers, fall leaf cover, or large canopies covering the street from curb to curb.
After deciding on these characteristics, you can then begin to strategically select species with the desired attributes, and then further refine that list through the core elements of this section. The core elements are based on principles of urban forest sustainability and best management practices for tree selection. It also recognizes current threats to trees in California such as drought and invasive species, as well as the future environmental challenges presented through climate change. Successfully completing this section will result in a tree palette consisting of a diversity of trees that provide ample canopy cover, are resilient to environmental threats, and aesthetically compelling.
Goals for Species Selection
- Selected tree species are climate resilient, long-lived, pest and disease resistant, low to moderate water users, emit low to moderate levels of biogenic volatile organic compounds, and have strong branch attachments.
- Create and enhance a diverse urban forest.
- Promote a safe and healthy urban forest for residents.
- Provide wildlife habitat opportunities.
Core Elements of Species Selection
- Species are regionally climate appropriate.
- Trees are known to be adaptable to future climate conditions.
- Selected species have a water use classification of landscape species (W.U.C.O.L.S.) water use rating of either very low, low, or medium.
- Species palette is diversified, with an emphasis on trees that are and will be well-adapted to local growing conditions.
- Species palette does not include palms, Italian cypress, or other species that provide minimal environmental services.
- Species are not invasive and do not require very high maintenance.
- 65% of trees are classified as medium or large shade trees (>40 ft tall at maturity) to maximize neighborhood benefits.
Elements for Gold
- Species are derived from a municipal or regional planting list.
- Species palette contains no more than 5% of one species or 10% of one genus of trees that are not native to the region.
- Species selected with guidance from SacTree staff.