Trees & Plantings
Trees help clean our air.
- Global forests removed about one-third of fossil fuel emissions annually from 1990 to 2007.
- Trees remove pollution from the atmosphere, improving air quality and human health.
- In Los Angeles, trees remove nearly 2,000 tons of air pollution each year.
- In Chicago, trees remove more than 18,000 tons of air pollution each year.
- In Greater Kansas City, trees remove 26,000 tons of air pollution each year.
- Roadside trees reduce nearby indoor air pollution by more than 50%.
- A study of 10 cities found community forests save an average of one life each year. In New York City, trees save an average of eight lives every year.
- Office workers with a view of trees report significantly less stress and more satisfaction.
Trees produce oxygen.
- One large tree can provide a day’s supply of oxygen for up to four people.
- More than 20% of the world’s oxygen is produced in the Amazon Rain forest
Trees help clean our drinking water.
- Forested watersheds provide quality drinking water to more than 180 million Americans.
- In 1997, New York City spent $1.5 billion to preserve the forested watershed that supplies New York City’s drinking water by purchasing thousands of upstate acres of forested watershed. A filtration plant large enough to clean New York City’s water supply would have cost more than $6 billion dollars.
- Today, New Yorkers enjoy some of the cleanest drinking water in the world, and New York City has won regional water taste competitions. Trees provide much-needed cooling.
Trees provide much-needed cooling.
- Trees lower surface and air temperatures by providing shade. Shaded surfaces may be 20–45°F cooler than the peak temperatures of unshaded materials.
- Trees cool the city by up to 10°F by shading our homes and streets and releasing water vapor into the air through their leaves.
- Evaporation of water from trees has a cooling influence.
Trees help reduce the effects of climate change.
- Trees absorb carbon dioxide (CO2), removing and storing the carbon while releasing the oxygen back into the air.
- In one year, an acre of mature trees absorbs the amount of CO2 produced by a car driven 26,000 miles.
- During one year, a mature tree will absorb more than 48 pounds of carbon dioxide from the atmosphere and release oxygen in exchange.
- Nearly 20 pounds of carbon dioxide are produced from burning one gallon of non-ethanol gasoline.
Trees help us save energy.
- Trees properly placed around buildings can reduce air conditioning needs by 30% and can save 20–50% in energy used for heating.
- The average Cincinnati community tree saves the average household $56 annually in cooling costs by reducing electricity use. More than 85,000 Cincinnati community trees save residents $4.8 million.
- Carefully positioned trees can reduce a household’s energy consumption for heating and cooling by up to 25%. Computer models devised by the U.S. Department of Energy predict that the proper placement of only three trees can save an average household between $100 and $250 in energy costs annually.
Trees benefit wildlife.
- Trees provide vital wildlife habitat.
- In British Columbia, Canada, more than 80 wildlife species depend on trees.
- Trees and forests provide important species range. Many animals have a range of hundreds of square miles. The mountain lion of North America, for instance, has a range of nearly 400 square miles.
Trees reduce crime.
- In Baltimore, a 10% increase in tree canopy corresponded to a 12% decrease in crime.
- Among minor crimes, there is less graffiti, vandalism and littering in outdoor spaces with trees as a part of the natural landscape than in comparable plant-less spaces.
- Chicago public housing residents with nearby trees and natural landscapes reported 25% fewer acts of domestic aggression and violence.
Trees are a good investment of our public dollars
- Every dollar spent on planting and caring for a community tree yields benefits that are two to five times that investment—benefits that include cleaner air, lower energy costs, improved water quality and storm water control and increased property values.
- In Indianapolis, each dollar invested in the city’s community trees yielded $5.55 in benefits.
- In New York City, it has been calculated that community trees provide $5.60 in benefits for every dollar spent on tree planting and care.
- In Cincinnati, the return on a $1 investment in the city’s community trees is $4.44.
- The mature street trees in Beverly Hills, California, are worth $450 million.
- A cost-benefit analysis of the Berkeley, California, tree canopy indicated that each camphor tree had an annual net benefit to the city and its residents of nearly $12,500, each shamel ash showed a $9,600 annual net benefit, and each London planetree had an annual net benefit of more than $8,700 per tree.
Trees increase our property values.
- In Portland, Oregon, homes with street trees sold for $7,130 more, on average, and 1.7 days more quickly.
- Neighboring houses within 100 feet of street trees sold for $1,688 more, on average.
- The sale premium of having street trees was the same as adding 129 square feet of finished space.
- In Fulton County (Atlanta), Georgia, mature trees positively influenced home sale prices. Homes sold for nearly $105,000 more in neighborhoods with mature trees.