Protecting the critical root zone
The critical root zone is the area that should be protected during construction to minimize impacts to a tree. Compaction or other impacts with the critical root zone can prevent the uptake of air, water and nutrients needed by the tree’s root system to survive. Grading or paving over the critical root zone can cause a tree to decline and die. Storage of construction equipment, soil stockpiles, masonry stockpiles and other heavy items can compact soil permanently even if they are only on the site for a short time. It may take several years for a tree to die from construction damage.
To prevent construction damage, fence off the critical root zone. Estimate the critical root zone by measuring the diameter of the trunk in inches, multiplying that number by 1.5, and using that number in feet as the radius of the protected area. For example, a ten-inch tree would need to have tree protection fencing located 15 feet away from the trunk; while a 20-inch tree would need to have tree protection fencing located 30 feet away from the trunk.
Thank you for helping to protect the urban forest that Minnetonka residents value.
For questions regarding protecting trees during construction, contact the Minnetonka natural resources division at 952.988.8422.
