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Tired of high energy bills? Consider some well-placed trees
This is a photo of a tree on the Oregon State University Campus
During these times of high energy costs and tightening budgets, home and business owners are encouraged to remember the energy savings provided by mature, well-placed trees.

Research has shown that trees can help reduce both heating and cooling costs. They save energy by keeping buildings cooler during the hotter months, and providing a windbreak during the winter. Deciduous trees (trees that lose their leaves in the winter) are especially helpful because they not only provide cooling shade during the summer, they let in much-desired sunlight during Oregon's cooler winter months.

Trees block out winter’s frosty winds
Trees help reduce energy consumption in the wintertime by blocking out wind. Cold winter winds enter homes through small openings or carry heat away from the building's outer surfaces. The most effective windbreaks on the north side of buildings are evergreen trees with crowns that extend to the ground, and branches that keep their foliage during the winter. Douglas-fir, junipers, spruce, cedar and true firs are some examples.

Strategically placed trees can be as effective as other energy-saving home improvements including insulation, or the installation of energy-saving windows and doors. Using trees and landscaping to reduce utility costs becomes even more critical in eastern and southern Oregon, since summers tend to be hotter, and winters colder in those areas than in the Willamette Valley or on the Oregon coast. Likewise, trees in general and conifers in particular are more effective in western Oregon for reducing storm water runoff and associated taxpayer costs.

Trees keep us cool during hot summer months
Trees lower air temperatures by evaporating water in their leaves. Shade trees can make near-by buildings up to 20 degrees cooler in the summer. Shade from trees reduces air conditioning needs, and makes non-air conditioned homes more comfortable. In fact, three large trees around a house can reduce air conditioning costs up to 30 percent.

According to the U.S. Environmental Protection Agency's web site, planting trees and vegetation is a simple and effective way to decrease local surface and air temperatures. Strategic planting around homes and buildings directly cools the interior of homes and buildings, decreasing air conditioning costs and peak energy demand.

Deciduous shade trees offer their best benefits since they shed their leaves during winter, admitting sunlight in the colder months. During the hotter months of summer, they’ll provide shade and block heat from the sun.

Remember to:
  • Place your trees on the south and west sides of buildings, and provide room for the mature size of the tree.  A tree that will reach a medium to large size should be located 15 to 20 feet from the side of a house.
  • Whenever possible, think about shading hard surfaces around your home like driveways, patios and sidewalks.
In addition to energy savings, trees and vegetation also improve our air quality, reduce carbon dioxide emissions, decrease storm water runoff, improve community livability, and increase property values.

Winter pruning
Remember, winter is a good time to prune trees, but “tree topping” is a detrimental practice that damages both the health and value of landscape trees. Tree topping – the indiscriminate cutting back of tree branches to stubs – weakens trees, leaves them vulnerable to insects and disease, and shortens their life spans.

Many people mistakenly "top" trees because they grow into utility wires, interfere with views or sunlight, or simply grow so large that they worry the landowner. “Proper pruning can remove excessive growth without the problems topping creates,” says Oregon Department of Forestry Urban Forester Paul Ries. “Topping creates hazard trees, but proper tree pruning creates healthy trees.” If the trees on your property are in need of pruning but you’re unsure just how to go about it, contact a certified arborist in your area for assistance.

For more information on proper tree care, the popular publication An Oregon Homeowner’s Guide to Tree Care may be downloaded from the Oregon Department of Forestry’s website at
If in doubt about what type of tree to plant, or how to pick the most suitable location, contact a certified arborist. A list of certified arborists for hire is available from the Pacific Northwest Chapter of the International Society of Arboriculture at www.pnwisa.org.

Tree care information is also available at the Oregon Department of Forestry’s website, at