The Benefits of Trees
Trees are incredible parts of our communities. They provide shade and beauty, serve as landmarks, and enhance our quality of life. But in what ways do they actually benefit us and our beloved ʻāina? Read through the benefits that trees offer below and learn why we love our trees so much!
Improved Air Quality
Urban trees and shrubs improve air quality by removing pollutants from the air including nitrogen oxides, carbon monoxides, halogens such as chlorine and fluorine, and ammonia.
Improved Water Quality
Tree roots play an important role with recharging groundwater by filtering out pollutants in our soil. Trees reduce stormwater which can pick up additional pollutants into waterways.
Attractive Urban Spaces
Trees serve as community landmarks and hold space in people's memories, often for multiple generations! From the parking lot to the storefront, having the trees and greenery providing shade and its foliage decorating the area is something that anyone can appreciate.
Combat Climate Change
Trees reduce carbon dioxide while releasing oxygen as they photosynthesize.
Welcoming Environments
Trees have great social value and can help communities come together. Trees reduce mental fatigue, help people relax, reduce aggression, promote people to spend time outdoors, increase surveillance, and discourage criminal activity.
Reduce Urban Heat Island Effect
The urban heat island effect occurs where urban areas are hotter than the surrounding countryside. Man-made impervious surfaces absorb and radiate heat which makes urban areas extra HOT! See how hot your community is with CCSR's Heat Map.
O'ahu Community Heat Map
Energy Savings
Shade from trees cool homes and businesses, reducing the need for air conditioning or other appliances. In some instances, tree shade can save energy costs anywhere from 15 - 50%.
HECO: Maximize Cooling Effect from Trees
Wildlife Habitat
Urban forests provide food and habitat for a variety of birds, animals, and fish. They provide valuable resting grounds for migratory and protected species such as our City bird, the Manu-o-Kū.
Increase Property Value
Aesthetics provided by trees play an important role in increased property value along with the many other benefits trees provide. Each large tree in the front yard adds about 1% to the resale value of a home. Large, specimen-sized trees can add 10% or more to property values.
Attractive Urban Spaces
- Aesthetic urban spaces: Trees serve as community landmarks and hold space in people’s memories, often for multiple generations! From the parking lot to the storefront, having the trees and greenery providing shade and its foliage decorating the area is something that anyone can appreciate.
- A welcoming environment: Trees have great social value and can help communities come together. Trees reduce mental fatigue, help people relax, reduce aggression, promote people to spend time outdoors, increase surveillance, and discourage criminals. Trees also function as open classrooms where children and adults can engage in ʻāina-based education.
- Increased property value: Trees on a residential and commercial properties can enhance property value. Aesthetics provided by trees play an important role in increased property value along with the many other benefits trees provide. Each large tree in a residential front yard adds about 1% to the resale value of a home. Large, specimen-sized trees can even add 10% or more to property values!
- Wildlife Habitat: Urban forests provide food and habitat for a variety of birds, animals, and fish. They provide valuable resting grounds for migratory and protected species such as our City bird, the Manu-o-Kū. Trees within urban forest parcels, along meadow edges, and stream banks contribute to the food, cover, and nesting needs for a wide variety of species. Forested areas along linear urban infrastructure such as highways, railroads, and utility lines serve as wildlife green corridors.
A Cleaner Oʻahu
- Improved Air Quality: Urban trees and shrubs improve air quality by removing pollutants from the air including nitrogen oxides, carbon monoxides, halogens such as chlorine and fluorine, and ammonia.
- Improved water quality: Trees help improve the overall quality of water by reducing stormwater runoff and filtering and absorbing pollutants. The foliage, branches, and stems intercept the rain and filter out pollutants. Its roots absorb that stormwater reducing surface runoff and the effects of water erosion. Less stormwater means less stress on our stormwater facilities, which improves our resiliency against any harsh storms in the future.
- Improved Soil Health: Trees attract large populations of microorganisms that supply organic matter, increase soil biodiversity, and supply the tree and soil with more nutrients. Tree roots also play an important role in helping the soil absorb water, which reduces the risk of wind erosion, improving the soil’s overall health.
- Combat climate change: Trees reduce carbon dioxide while releasing oxygen as they photosynthesize.
Cool Oʻahu and Save Energy
- Cooling Oʻahu: Trees help lower and stabilize temperatures around communities by shading impervious surfaces and absorbing heat generated by those roads, sidewalks, nearby buildings, and vehicles. Shade from trees help to lower nearby water temperatures and the ambient temperature by an average of 3 to 10 degrees Fahrenheit. Trees in urban spaces minimize the Urban Heat Island Effect.
- Energy savings: If planted strategically, trees can provide shade for your business or home that will decrease the need to use air conditioning or other appliances to moderate temperatures. By having trees, the shade could help save up to 50% of a typical residence’s annual air conditioning costs (American Public Power Association)!
What is the Urban Heat Island Effect?
The urban heat island effect is a phenomenon where the metropolitan areas are generally hotter than the surrounding countryside. Without as many trees and green cover, the impervious surfaces of our man-made structures absorb sunlight and convert it into heat energy. This heat energy increases the ambient temperatures in city centers, where the effects have been measured 5 to 9 degrees higher than in the surrounding countryside.
Thanks to the work of the Climate Change, Sustainability, and Resilience Office, the image below details the urban heat island effect that can be seen throughout Oʻahu. We can see that the more urbanized and developed areas correlate with higher temperatures than their inland counterparts. See the full interactive map here!
