Branching Out Against the Heat

It’s the hottest time of the year again here in Virginia, and many of us are wishing for a cool dip in the pool after walking from our hot car to the front door of our workplace. The most recent high was 96 degrees Fahrenheit, and it often feels like it can only get hotter from here on out. But, lucky for Northern Virginians, NVCT and our partners’ work is helping build a cooler future every day.

In the most recent installation of our Nearby Nature Network webinar series, Casey Trees’ Tree Stewardship Manager, Spenser Balog, taught attendees about the importance of urban tree canopy. Casey Trees is a nonprofit based in D.C. whose mission is to protect, restore, and expand D.C.'s tree canopy. Casey Trees started as a tree planting organization in 2002. After years of serving as D.C.'s state nursery, they expanded their mission to increase tree canopy by becoming an accredited land trust. Casey Trees, like NVCT, holds easements on preserves it owns and on private properties with landowners. NVCT and Casey Trees became partners because of our shared interest in protecting green spaces for the public, promoting sustainable development, and increasing tree canopy coverage in our cities!

Spenser covered why trees benefit cities and how we can all do our part to take care of our urban forests. Many of our members and followers not only know about the benefits of nearby nature but also prefer to have nature within arm’s reach. This year’s Nearby Nature Network summer seminar dove deeper into how to effectively increase tree coverage in our cities and opened discussion of nuanced methods for enhancing existing tree canopy. This webinar was the perfect example of why working with partners is so important. Through collaboration, we help each other improve conservation efforts and share that knowledge with others.

The timing is no coincidence. Summer heat waves are here. For those of us in the city, that means higher temperatures due to concrete and asphalt radiating heat from the sun. Tall buildings clustered close together also make it difficult for wind to move through smoothly, making it harder for heat to dissipate into the air. This phenomenon is known as the urban heat island effect. Urban areas tend to be hotter than their rural neighbors. Cities can be 1 to 7 degrees hotter than surrounding rural areas. 

Nature’s air conditioning is wind blowing through a shady forest. Trees and local green spaces make summer fun possible, not just because they create great spots to bask in the summer breeze. Trees and vegetation release water vapor as a byproduct of photosynthesis, which in turn helps cool the surrounding air. Photosynthesis also removes carbon from our atmosphere. Beyond lowering temperatures and combating climate change, trees also provide us with clean air, prevent erosion, filter water and rainfall before they enter our drinking water sources,  and even boost our mental health.

Mature trees provide exponential value to the environment. In one year, a mature tree can absorb up to 48 pounds of carbon, removing it from our atmosphere and lessening the effects of greenhouse gases. Larger mature trees also provide habitat for wildlife living in the branches, inside the trunks, or beneath exposed root systems.

Spenser emphasized that the biggest threat to tree canopy in our cities is development. Healthy mature forests are often clear cut for new buildings. This not only rids the area of the benefits mature trees provide, but also further isolates scattered forest patches. Once these trees are lost, the value they provide takes decades to recover. Under ideal conditions, it can take 20 to 50 years for a newly planted tree to provide the same level of carbon sequestration, cooling, and habitat as a mature tree. Casey Trees and NVCT advocate building on already disturbed land, such as an unused parking lot or an area stripped of vegetation.

The core of our work at NVCT, land protection, ensures nature spaces in our cities exist and stay in place forever. While planting trees is beneficial to the environment, sprinkling trees into a disturbed environment is not the most effective method of recovery. Fifty percent of newly planted trees along city streets and neighborhood walkways die within two years. Trees rely on multiple conditions to reach maturity, and those necessities are difficult to meet in urban settings. Protected land ensures that mature trees surrounding remain rooted where they are and continue to improve the surrounding land. This creates ideal conditions for new trees, ensuring forest succession. NVCT protects over 500 acres of green space within Arlington County and the City of Alexandria, including historic homes, pocket parks, and community gardens. Whether a property is protected because it borders an existing park, has a historic home, or has the potential to become a community resource, its natural features are stewarded by NVCT forever. These properties create a network of forest patches that provide connectivity for wildlife and widespread benefits for residents of Arlington and Alexandria.

Deloitte Impact Day volunteers planting native plants and tree saplings at Little Hunting Creek Preserve in the City of Alexandria

Instead of looking for a summer getaway to escape the heat, you can enjoy cool breezes, shade, and lower temperatures in your own city within your lifetime.  There are easy ways that you can help restore and improve the health of trees near you.  

• Create a welcoming space for local pollinators. Working on your summer garden? Here’s some tips courtesy of NVCT: https://www.nvct.org/post/top-10-natives-to-plant-this-summer

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  Nearby Nature Network: Urban Tree Stewardship with Spenser Balog (Casey Trees - Tree Stewardship Manager)

  
  

• Water, prune, and mulch your trees! Water your trees regularly, prune off dead or diseased branches, and mulch around the base to insulate the roots during cold months and protect them from weeds year-round.

  

  Nearby Nature Network: Urban Tree Stewardship with Spenser Balog (Casey Trees - Tree Stewardship Manager)

• "Leaf" dead leaves on your lawn after breaking them up so they can nourish the soil. They also serve as good mulch around tree trunks!

• Remove invasives like English ivy that wrap around trees and cut off their access to water, nutrients, and sunlight.

  
  

The last and our favorite tip for improving tree canopy in your neck of the woods is to be a part of our work! Remove invasives with NVCT or Casey Trees on protected properties! Both our organizations rely on the support of engaged residents to accomplish our work and you are always welcome to help enact environmental change.