How would you like to save up to 30% on your heating and cooling costs? You can if you plant the right kind of trees in the right locations. According to the U.S. Department of Agriculture, the cooling power of a healthy shade tree equals 10 room-size air conditioners running 20 hours a day. All it takes is placing the right trees in the right spots.
As the sun rises, your house starts to bake. Having big, leafy trees in the southeast corner shades your house all morning. As the sun passes overhead, the trees on the southwest side take over the job of cooling your house. The hot afternoon sun is blocked by trees on the west side.
As strange as it may seem, planting shade trees directly south of your house won't provide the shade you expect. When the sun is overhead, the shadow doesn't cover your house. Also, the tree trunk will shade your house in the winter, when the sun is lower. Trees on the south side have to be at least 30 feet away and really tall to be effective.
In most places, winter winds roar in from the north and northwest. They push cold air into the tiny cracks in your house. Planting a windscreen of evergreen trees can take some of the punch out of those winds and keep your house warmer. Just be sure to make your wind screen wider than your house, since the wind will whip around the edges.
Shading your air conditioner can save you around 10% on your electricity bill. There are plenty of small trees or tall shrubs that will do the job. Ask your local nursery for help.
When you plant trees, be careful with exotics. They can have nasty unintended consequences. Norway maples, for instance, are good for shade, but they can also shade out grass, bushes and flowers, so nothing much can grow under them. Also, they're invasive, and are crowding out native species in Eastern forests. Native sugar maples are a better idea.
Hickories, serviceberry, hazelnut and other food-bearing trees are great options to plant. They look beautiful in landscaping, they provide the shade you want, and they grow food and shelter for birds and other wildlife. And not just for them - serviceberries are delicious for breakfast, tasting something like blueberries.
Sometimes it's hard to put a dollar value on what trees do, but that hasn't stopped some experts. The American Forestry Association (1985) estimated the economic and environment benefits of a tree at $57,000 over a 50-year lifespan. The U.S. Forest Service says that, over a 50-year lifetime, a tree generates $31,250 of oxygen, provides $62,000 worth of air-pollution control, recycles $37,500 worth of water, and controls $31,250 worth of soil control (USDA Forest Service Pamphlet #R1-92-100). Plant a few trees, make Mother Nature happy and enjoy the savings.