The Ecosystem Services of Trees
A WHOLE WORLD IN ONE ORGANISM
Trees are beautiful to look at, can provide a home for a variety of species, and assist in certain processes that allow biological life on Earth to prosper. Before you read on any further, take a moment to envision your favorite tree - the song of a bird upon its branches, the way that sunlight filters in through the leaves, and the way it sways with the wind. How it shakes and dances, how it lives and breathes. Take a moment to really appreciate this beautiful organism in all its glory.
Proceedings of the National Academy of Sciences of the United States (PNAS) claims that there are approximately 73,000 tree species globally, among which 9,000 species have yet to be discovered. Estimates conclude that roughly 40% of undiscovered tree species are in South America, and almost ⅓ of all tree species yet to be discovered are rare. In this sense, rare means very low populations and limited spatial distribution, likely to be found in remote tropical lowlands and mountains. The idea of those trees yet to be discovered highlights the vulnerability of global forest biodiversity to anthropogenic changes in land use and climate. These threats can influence rare species and global tree richness as a result.
Since Maine has a special place in our hearts, let’s take a minute to think about all of the trees present in this state alone. With an estimated 17.5 million acres of forest land covering 89% of the land area, Maine has the highest percentage of forest cover of any state in America. In 2019, there were approximately 23.41 billion trees. Balsam fir is the most numerous tree species in Maine based on the number of trees alone. In terms of volume, red spruce is the most dominant (ME Dept. of Agriculture). The Maine Forest Service claims there are about 76 tree species in Maine - some recurring “family members” include Spruce, Oak, Pine, Ash and Maple.
Photograph taken by Kayla Saunders (Maine, 2022)
In addition to their soothing presence and aesthetically-pleasing nature, trees are vital parts of our planet’s systems and processes. The Nature Conservancy summarizes some of the top contributions of trees to our natural world in a 6-point list:
Absorb the greenhouse gasses that cause climate change through photosynthesis. They are vital in regulating gasses in the atmosphere.
Boost our mental and physical health alike. Some studies show that time in nature correlates with a drop in anxiety and depression.
Filter the air we breathe. They remove particulate matter from the air and are most effective in a 100-foot radius around the tree.
Provide a home to wildlife. Trees create habitats at ground-level and the forest canopy and everything in between. Fungi, insects, plants and animals all can use a tree for protection in different ways.
Regulate temperature. A tree’s shade acts like a natural air conditioning system.
Filter water. Trees store and filter more than half of the water supply in the United States.
Without trees, human life would look very different if it were to exist at all. There are different natural sources of carbon removal and air/water filtration, but trees do much more. Branches are a giant playground. Root systems hidden highways. Leaves and seeds provide a wonderful lesson of how life can sprout where it truly begins, and can come back after challenging conditions given the right circumstances. We owe it to ourselves and to future generations to preserve trees, and the services they provide by extension.
The best tool you can have is knowledge. Learn about the trees local to you and how to protect and preserve them. Get to know and love them. If you can, plant them, or support organizations that do. Visit forests often, and teach your kids about them through books and outdoor exploration alike. Consciously try to appreciate trees and all the organisms that make a home of them. We are a part of this ecosystem too, and as Earth’s most dominant species it is up to us to protect the species we share it with. By saving trees, we are saving ourselves.
“A society grows great the day that old men plant trees whose shade they know they’ll never sit in.”