Combat heat by planting more trees and pruning them properly


Higher temperatures are a reality. One answer to help reduce the heat is planting more trees.

The movement to plant more trees on this planet is happening worldwide. Organizations such as the Nature Conservancy’s “Planting 1 billion tree” campaign across the world to “re-green” our planet “one tree at a time” to reduce climate change. The Arbor Day Foundation also has a tree planting campaign, “Now is the Time. The Time for Trees.” Closer to home, Oahu’s nonprofit group “Trees for Honolulu’s Future” has goals of 35 percent tree canopy by 2035 and to plant 100,000 trees by 2025.

Maui Green & Beautiful, a nonprofit with roots on Maui since the 1950s, will plant a minimum of 50 trees by 2020 in honor of the 50th anniversary of Earth Day. The trees will be planted in community spaces in the county such as schools, parks, places where people can enjoy the benefits of the trees. MG&B encourages all community members to join in by planting their own trees too. There can never be enough trees on Maui!

Properly pruned trees according to the International Society of Arboriculture pruning standards are also the answer to help combat the heat, which means no “topping” or severely pruning trees, especially in parking lots and along roads. Just think how pleasant it is to drive through the Olowalu tree tunnel in the daytime and get a break from the hot sun.

When you park your car during the day in a parking lot, or “heat island” (defined as built-up areas that are hotter such as parking lots, buildings, roads), aren’t we all looking to park under a sprawling tree canopy? The tree shades the car and the water vapor released from the leaves of the tree cool the area under the tree.

This can’t happen in most parking lots on Maui due to the unfortunate trend of improperly removing so much canopy of the tree or, even worse, “topping” the tree. Remember, when the leaves are cut off the tree is stressed and pushes out more growth because it needs its leaves for food production. Stressed trees also attract insects and new branches are hazards because they are not as strong as the original branches.

One positive example of a shady and cool parking lot on Maui is at UH-Maui College on the Kaahumanu side of the campus, which was planted by Maui’s very own tree expert, Ernest Rezents. Trees were also recently planted along sidewalks between buildings at the college to eventually keep students cool so the air conditioning doesn’t have to be set as cold. Trees can save energy use too.

Stopping the removal of healthy mature trees, especially in our urban areas, combat rising temperatures too. It takes years for a young tree to give the same benefits of a large tree. Hardscapes like sidewalks and pavement can get uplifted by growing tree roots; solutions are there to save the tree and at the same time repairing the hazard. Trees are just as important as our hardscapes, and buildings and do need to be maintained and cared for on a regular basis.

Trees are also the answer to filtering our air and controlling soil erosion. The recent fires on Maui made our air quality extremely bad with ash and now the dust. Trees filter particles out of the air and hold down the soil. Would windbreaks of trees prevented the fire from spreading or help in controlling the dust?

Trees are important from the forests to the urban areas. There are many examples of the community wanting more trees. The Maui Nui Botanical Garden annual tree giveaway always has such a large turnout of island residents. The Maui County Council amended the Maui County Exceptional Tree list by including over 500 more trees as exceptional last year, nominated by residents, showing the importance of preserving mature trees throughout Maui County.

Excellent resources are the Maui County Planting Plan and the Trees are Good website.

For more information on the Maui Green & Beautiful planting project, go to www.mauibeautiful.org or contact mauigreenbeautiful@gmail.com.

* Elaine Malina is a current board member and past president of Maui Green & Beautiful. She has been a International Society of Arboriculture certified arborist since 1997 and has more than 35 years’ experience in the professional landscape industry on Maui.