Why Plant Trees?

Carol Moser
Richland City Council
Mid-Columbia Community Forestry Council

Trees Are Pretty

They come in all variety of shapes and sizes, and they look so interesting throughout the year.  In the summer they are fully dressed in leaves of green.  In the fall they go to the ball and change into their fancy colors and put on a real show.  In the winter when they are sleeping, we see them in their naked form and their branches are bare, but especially beautiful after a snowfall, or ice storm.  Then they wake up again in the Spring, and celebrate being one year older by blossoming and putting on perfume, and looking especially gorgeous.  Unlike human beings, trees enjoy getting old because they become even more magnificent and beautiful and valuable year after year after year.  (The oldest trees are California’s bristlecone pines and giant sequoias.  Some bristlecone pines have lived over 4,000 years!  The oldest sequoias are about 3,500 years old.)

Trees Produce Food, Yield Special Products, and Provide Shelter for Birds and Animals

Trees produce fruit like apples, oranges, peaches, plums, apricots, cherries, nectarines, avocados, figs, olives, lemons, pears, papaya, pomegranates, dates, and guava to name a few.  They also produce nuts that we love to eat such as almonds, cashews, coconuts, pecans, walnuts, brazil nuts, and pistachios.  Special products such as balsa wood, cacao, cinnamon, clove, cork, nutmeg, rubber, witch hazel, sassafras, camphor, coffee, and turpentine are made from various parts of trees.  Trees and forests provide homes for many different species of animals like squirrels and birds.

Trees Increase Home Property Values

Office and industrial sites are in greater demand & earn higher sales and rental values.  Houses on tree-lined streets can command higher prices than houses in more barren areas.

Trees Have an Interesting Effect on People

·      Trees make us feel happy and connected with nature.

·      Trees help us recover from illness faster. 

·      Trees restore our spirit.

America is a nation of cities and towns - more than 80 percent of the U.S. population lives in urban areas.  Plants, forests and ecosystems are important in cities.  Social scientists have discovered that parks, green spaces and trees are more than the “lungs of the city” or “pollution scrubbers.”  They affect our everyday moods, activities and emotional health.  Proof of psychological and social benefits gives us more reasons to plant more green in cities.

Trees calm down people when they are feeling stressed out.  They reduce our feelings of anxiety and irritability.  Dr. Rachel Kaplan, author of The Experience of Nature:  A Psychological Perspective, surveyed desk workers about their rate of illness and level of job satisfaction.  Some study participants could view nature from their desks, others could not.  Those without, when asked about 11 different ailments, claimed 23% more times of illness in the prior six months.  Desk workers with a view claimed the following satisfactions more often than their non-view colleagues:  1) found their job more challenging, 2) were less frustrated about tasks and generally more patient, 3)  felt greater enthusiasm for the job, 4)  reported feelings of higher life satisfactions, and 5)  reported better overall health.

Trees Are Essential to Our Health and the Health of our Environment

Trees breathe in carbon dioxide, and produce oxygen.  People breathe in oxygen and exhale carbon dioxide.  A typical person consumes about 38t lb of oxygen per year.  A healthy tree, say a 32 ft tall ash tree, can produce about 260 lb of oxygen annually - two trees supply the oxygen needs of a person for a year!  They help reduce pollution by capturing particulates like dust and pollen with their leaves. A mature tree absorbs from 120 to 240 lbs of the small particles and gases of air pollution.  They help combat the effects of “greenhouse” gases, the increased carbon dioxide produced from burning fossil fuels that is causing our atmosphere to “heat up”.

Trees Maintain and Improve Surface Water Quality

They reduce the amount of grease and oil transported to streams when the hair-like root fibers filter the groundwater, and trap nutrients and pollutants that could contaminate it..  Leaves and branches slow the movement of rain to the ground, allowing it to soak in slowly, so they help cities moderate storm water and storm water effects.  In one study, 32 feet tall street trees intercepted rainfall, reducing storm water runoff by 327 gallons.  Without trees, heavy rains can wash soil into streams and rivers. Scientists from the U of W are designing trees to “sponge up” and convert dangerous chemicals to products as harmless as table salt.!  A special gene in the tree triggers the release of up to 10 times the base concentration of a naturally occurring enzyme that decomposes toxins.

Trees Increase Energy Conservation Benefits by Reducing Energy Use

Trees help cool down the overall city environment by shading asphalt, concrete and metal surfaces.  Buildings and paving in city centers create a heat-island effect.  A mature tree canopy reduces air temperatures by about 5-10_ F. influencing the internal temperatures of nearby buildings.  Asphalt lasts longer in areas that are more protected by shade.  In our own summer environment in the Tri-Cities, we all prefer to park under the shade of a tree while we shop!  A 25 foot tree reduces annual heating and cooling costs of a typical residence by 8 to 12 percent, producing an average $10 savings per American household.  Proper tree plantings around buildings can slow winter winds, and reduce annual energy use for home heating by 4-22%.  They help moderate temperatures by working as natural barriers to wind, snow, rain, and solar rays.  Through evapo-transpiration, trees add moisture and cool the air.  

Trees Aid in Traffic Control and Trees Separate Pedestrians and Vehicles, Providing Safer Walking Conditions

Trees are used in Seattle in the landscaping of traffic circles.  Traffic circles are being used in residential neighborhoods to calm traffic, but their greatest benefit has been shown to reduce accidents.  Seattle’s Neighborhood Traffic Control Program (NTCP) got its start as an outgrowth of programs to assist and improve deteriorating neighborhoods.  Demonstration projects tested a variety of traffic control devices, with the most successful device being the traffic circle.  Trees are often planted in the circles because they can change the character of the street, and interrupt an otherwise continuous line-of-sight for motorists, causing the motorist to slow down.

Trees Complement Economic Development

The appearance of a business district can send many messages, and according to a research project at the University of Washington, consumers are drawn to places that look inviting, pleasant, and orderly.  Results suggested that consumers enjoy having trees in retail shopping districts, and that trees are good for business.  People linger and shop longer along tree-lined streets.  Across our nation, many cities are revitalizing shopping districts to create vibrant, vital consumer environments.  Trees create an immediate visual impact, and send positive messages about the appeal of a district.  Trees contribute to a community’s image of being livable.  Business and industry want to locate in communities that have a positive image, and trees lend to that image.

Trees Are a Critical Part of the Urban Ecosystem

Trees provide a buffer between land uses.  They can define and screen different land use areas within the urban growth area.  Because trees can modify the humidity in the air, they help as noise buffers, but their value is mostly visual, creating a physical barrier between different land uses.  They buffer parks and residential uses from high traffic areas, commercial centers, and changes in zoning.  Trees play a vital role in making our cities more sustainable and livable.