The City provides tree guards for new street trees under very limited circumstances. Property owners are responsible for the installation and maintenance of the guards, unless they have been installed by the Department of Parks and Recreation (DPR).
If you are a property owner and want a tree guard around a City tree, you can make a donation toward guard installation to the New York Tree Trust, which is a fund managed by DPR. You can make the tax-deductible donation by calling (718) 760-4009.
You can also apply for a Tree Work Permit and, after DPR approval, hire a private contractor to install a tree guard or construct a tree guard on your own which complies with DPR standards.
For more information about the tree guard permitting process, send an email to Central.Forestry@parks.nyc.gov.