Benefits of Trees

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Most trees and shrubs in cities or communities are planted to
provide beauty or shade. These are two excellent reasons for
their use. Woody plants also serve many other purposes, and it
often is helpful to consider these other functions when selecting
a tree or shrub for the landscape. The benefits of trees can be
grouped into social, communal, environmental, and economic
categories.

Social Benefits

We like trees around us because they make life more pleasant.
Most of us respond to the presence of trees beyond simply
observing their beauty. We feel serene, peaceful, restful, and
tranquil in a grove of trees. We are "at home" there. Hospital
patients have been shown to recover from surgery more quickly
when their hospital room offered a view of trees. The strong ties
of people and trees are most evident in the resistance of
community residents to removing trees to widen streets. Or we
note the heroic efforts of individuals and organizations to save
particularly large or historic trees in a community.

The stature, strength, and endurance of trees give them a
cathedral-like quality. Because of the potential for long life, trees
are frequently planted as living memorials. We often become
personally attached to trees that we or those we love have
planted.

Communal Benefits

Even though trees may be private property, their size often makes
them part of the community as well. Since trees occupy
considerable space, planning is required if both you and your
neighbors are to benefit. With proper selection and maintenance,
trees can enhance and function on one property without
infringing upon the rights and privileges of neighbors.

City trees often serve several architectural and engineering
functions. They provide privacy, emphasize views, or screen out
objectionable views. They reduce glare and reflection. They direct
pedestrian traffic. They provide background, soften, complement,
or enhance architecture.

Trees bring natural elements and wildlife habitats into urban
surroundings, all of which increase the quality of life for residents
of the community.

Environmental Benefits

Trees alter the environment in which we live by mode rating
climate, improving air quality, conserving water, and harboring
wildlife. Climate control is obtained by moderating the effects of
sun, wind, and rain. Radiant energy from the sun is absorbed or
deflected by leaves on deciduous trees in the summer and is only
filtered by branches of deciduous trees in winter. We are cooler
when we stand in the shade of trees and are not exposed to
direct sunlight. In winter, we value the sun's radiant energy; and
because of this, we should plant only small or deciduous trees on
the south side of homes. Wind speed and direction can be
affected by trees. The more compact the foliage on the tree or
group of trees, the greater the influence of the windbreak. The
downward fall of rain, sleet, and hail is initially absorbed or
deflected by trees and this provides some protection for people,
pets, and buildings. Trees int ercept water, store some of it,
reduce storm run-off, and the possibility of flooding. Dew and
frost are less common under trees because less radiant energy is
released from the soil in those areas at night.

Temperature in the vicinity of trees is cooler than that away from
trees. The larger the tree, the greater the cooling. By using trees
in the cities, we are able to moderate the heat island effect
caused by pavement and buildings in commercial areas.

Air quality can be improved through the use of trees, shrubs, and
turf. Leaves filter the air we breathe by removing dust and other
particulates. Rain washes the pollutants to the ground. Leaves
absorb carbon dioxide from the air to form carbohydrates that are
used in the plant's structure and function. In this process, leaves
also absorb other air pollutants - such as ozone, carbon
monoxide, and sulfur dioxide and give off oxygen.

By planting trees and shrubs, we return to a more natural, and
less artificial environment. Birds and other wildlife are attracted to
the area. The natural cycles of plant growth, reproduction, and
decomposition are again present, both above and below ground.
Natural harmony is restored to the urban environment.

Economic Benefits

Property values of landscaped homes are 5-20% higher than those
of non-landscaped homes.

Individual trees and shrubs have value, but the variability of
species, size, condition, and function makes determining their
economic value quite difficult. The economic benefits of trees can
be both direct and indirect.

Direct economic benefits are usually associated with energy
costs. Air conditioning costs are lower in a tree-shaded home.
Heating costs are reduced when a home has a windbreak. Trees
increase in value from the time they are planted until they mature.
Trees are a wise investment of funds since landscaped homes are
more valuable than non-landscaped homes. The savings in energy
costs and the increase in property value directly benefit each
homeowner.

The indirect economic benefits of trees are even greater. These
are available to the community or region. Lowered electricity bills
are paid by customers when power companies are able to use
less water in their cooling towers, build fewer new facilities to
meet peak demands, use reduced amounts of fossil fuel in their
furnaces, and need fewer measures to control air pollution.
Communities can also save if fewer facilities must be built to
control storm water in the region. To the individual these savings
are small, but to the community, reductions in these expenses are
often in the thousands of dollars.

Trees Require an Investment

Trees provide numerous aesthetic and economic benefits but
also incur some costs. You need to be aware that an investment is
required for your trees to provide the benefits that you desire.
The biggest cost of trees and shrubs occurs when they are
purchased and planted. Initial care almost always includes some
watering. Leaf, branch, and whole tree removal and disposal can
be expensive.

To function well in the landscape, trees require maintenance.
Much can be done by the informed homeowner. Corrective
pruning and mulching will give trees a good start. Shade trees,
however, quickly grow to a size that may require the services of a
professional arborist. Arborists have the knowledge and
equipment needed to prune, spray, fertilize, and otherwise
maintain a large tree. Your garden center owner, cooperative
extension agent, community forester, or consulting arborist can
answer questions about tree maintenance, suggest treatments, or
recommend qualified arborists.

The PHC Alternative

Maintaining mature landscapes is a complicated undertaking. You
may wish to consider a professional Plant Health Care (PHC)
maintenance program which is now available from many landscape
care companies. Their program is designed to maintain plant vigor
and should initially include inspections to detect and treat any
existing problems which could be damaging or fatal. Thereafter,
regular inspections and preventive maintenance will ensure plant
health and beauty. Refer to our Plant Health Care brochure for
more information.

For Additional Information

This brochure is one in a series published by the International
Society of Arboriculture as part of its Consumer Information
Program.
Tree Care Information

Why Hire an Arborist

Tree Benefits

Tree Values

Tree Selection

Buying High Quality Trees

Avoiding Tree & Utility Conflicts

New Tree Planting

Mature Tree Care

Plant Health Care

Trees and Turf

Proper Mulching Techniques

Pruning Young Trees

Pruning Mature Trees

Why Topping Hurts Trees

Insect & Disease Problems

Avoiding Tree Damage During Construction

Treatment of Trees Damaged by Construction