Property
owners then face costs for removal and replacement. Protecting trees
and their roots is an integral part of construction projects like
remodeling, sidewalk and driveway installation, landscaping, or
utility work.
Construction-related tree injury occurs through physical damage like
equipment collisions, soil compaction, or cutting and severing
roots. Injury also occurs through environmental changes like sudden
exposure to wind and sun through pruning, fluctuations in soil
moisture, or soil nutrient availability.
Identifying tree stress is essential for early intervention.
However, because trees may exhibit symptoms months or years after
damage occurs, several years may pass before symptoms arise from
soil compaction or root suffocation. Because of this delay, it can
be difficult to recognize the relationship between construction
damage and its symptoms.
Injuries might result in leaf wilt, early fall color,
dieback, stunted growth, and premature leaf or needle drop. Evidence
of physical injury can be visible wounds on the trunk or exposed
roots.
To protect trees, mark the placement of proposed structures, parking
areas, sidewalks, and utilities. This will aid in establishing a
tree protection zone for trees that will remain. It is important to
note that the roots extend far beyond the tree’s canopy, and
protecting the largest root zone possible will greatly benefit a
tree’s health. Prioritizing requires careful consideration of each
tree’s species, health, and structural integrity. Give precedence to
healthy, mature trees that benefit the ecosystem as a source of food
or shelter for wildlife.
Certified arborists can assist in preservation decisions by
providing insight into tree health. These professionals adhere to
accepted standards regarding tree management, protection during
construction, and many other industry requirements.
Steps to minimize construction damage
Communicate with contractors about protecting mature trees. Install
construction fencing around tree root zones to create a physical
barrier and visual reminder for workers.
Restrict heavy machinery and construction traffic from entering tree
protection zones to mitigate soil compaction and root damage. Tree
roots are concentrated in the top 6” to 18” of soil. [to top of second
column] |
Use mulch and temporary ground cover to prevent soil
compaction during construction.
Remove undesirable trees over winter when leaves are absent to
lessen the degree of sunburn on nearby trees.
Consider tunneling utilities beneath tree roots instead of trenching
to minimize root disturbance and preserve root structure. Tunnel at
least 2’ away from the trunk and at least 2’ underground.
Avoid significant grade changes near trees to prevent root exposure
and destabilization. Conversely, piling more soil around trees can
smother roots.
Steps to encourage recovery and long-term health
Aerate compacted soil around trees to improve root oxygenation and
nutrient uptake.
Provide supplemental irrigation to trees, especially during dry
periods, to aid in root establishment.
Apply a 2” to 4” layer of mulch around the base of trees to prevent
soil compaction, conserve soil moisture, suppress weeds, and protect
the trunk from mowers and trimmers. Keep mulch several inches away
from the trunk to avoid rot and other problems.
Regularly inspect trees for signs of stress or damage and address
issues promptly.
Protecting trees and, specifically, roots during construction
requires a proactive and multidimensional approach. By understanding
the types of damage, recognizing symptoms of distress, making
informed preservation decisions, and using preventive measures and
proper care practices, communities can safeguard more trees in our
urban landscapes.
For more on protecting and caring for trees, connect with a local
University of Illinois Extension office at go.illinois.edu/ExtensionOffice.
[SOURCE: Sarah Vogel, Horticulture
Educator, University of Illinois Extension]
|