SAVE YOUR TREES

This pamphlet was created by the Ontario Urban Forest Council to provide information to homeowners or anyone considering modifying their property where the construction activities may affect trees. Much concern has been expressed by the OUFC over the sale of "treed lots" to home buyers who pay a premium for land only to watch the trees ultimately become very expensive firewood.

Trees play an important part in our day to day lives when you sit in the shade of your backyard on a hot summer day or explore a nearby forest in your neighbourhood. Trees add a certain quality of life and create a sense of maturity and stability to a neighbourhood. Trees and other landscaping add value to your home as well as habitat for wildlife. Taking steps to protect these assets before, during and after construction will enhance their ability to survive.

Proper care should be provided for trees during any construction or grade changes. Trees, unlike people , do not have the ability to leave an area while their surroundings are undergoing change. The conditions discussed will vary from site to site and more technical advice can be provided by a tree care consultant such as a local Arborist or Urban Forestry 'Consultant.

WHAT CAN YOU DO?
During the design stage for the site, protection plans for existing trees should be created. Having trees evaluated at this time will identify trees that should be preserved. Your tree Care consultant will recommend guidelines to minimize the trauma of construction to trees.

POSSIBLE TREE DAMAGE DUE TO CONSTRUCTION CROWN DAMAGE
Branches are often bent or broken during construction. Depending on the severity and timing of any root damage, dieback symptoms in the top of the crown may be seen immediately and even 5 years after the end of construction. Early fall leaf colouration can also be a symptom of tree damage.

TRUNK DAMAGE
If construction equipment and supplies are located around a tree, damage to the trunk may occur. Anything that bumps or gouges into the trunk will kill the water and food conducting tissues, limiting the transport of these two materials within the tree. Fastening ropes and chains around the tree trunks to use for leverage can result in the same damage.

ROOT DAMAGE
Machinery driving over roots compacts the soil. Smaller pores in the soil reduces water and oxygen movement and makes root growth more difficult.

If tree roots are not protected by a sturdy fence erected at a minimum distance of the dripline of the tree (outermost tips of the tree), a number of damaging conditions can result - compaction, cur roots, grade changes and soil contamination

Roots torn during construction are usually ripped out of the soil by digging machinery. This kills and damages roots along their entire length. If construction occurs close to tree trunks, all roots beyond the excavation are cut and cease to supply water, oxygen and nutrients to the tree.

Lowering the grade from the original level exposes roots to drying and kills them. Raising the grade smothers roots. Tree roots need oxygen and raising the grades reduces oxygen availability.

TREE CARE BEFORE AND AFTER CONSTRUCTION
Before construction begins, a Tree Care Consultant should check all trees on the property and neighbouring properties to evaluate which trees can and should be protected from construction activities. Insect and disease problems should be identified and control programs, if needed, should be set up to prevent additional stresses to trees. Periodic inspections by the Arborist during construction should ensure maximum protection for your trees and increased tree survivability.

Deadwood, diseased wood, water sprouts and branches showing structural defects should be removed from trees.

To preserve the rooting environment, it is important to erect a sturdy fence around the tree at a minimum distance of the dripline. If trees are grouped together, one fence should be placed around the entire perimeter. This will minimize construction activity over tree root systems and will also protect tree trunks from mechanical injury.

A 5 - 10 cm layer of organic material (leaves, compost, wood chips) should be spread over the root systems of trees. This will help preserve moisture in the soil.

If possible, do not allow the grade to change within the dripline of trees. Normal drainage patterns around trees should be maintained to prevent water accumulation at tree bases. Consult your Arborist when plans require a grade change.

If drought conditions occur during construction, tree leaves may appear wilted. Water once a week and allow enough water to soak into the soil to a depth of about 30 cm.

Trees require easy access to water and oxygen. Aeration, the creation of small holes scattered over the root system of the tree, will help allow water and oxygen to move into the soil

If the soil has been found to be deficient in required nutrients, fertilization may be of benefit to the tree.

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