An excellent way to protect street trees from many urban-specific threats is my installing a tree guard. These fence-like structures provide a visual cue to pedestrians, dog-walkers, and automobilists that the tree bed should not be trafficed upon. More information about permits and structural dimensions can be found on the Department of Parks and Recreation's website.
What makes for a good tree guard? Although many people around the city place tree guards with the best intentions, poorly designed projects can actually increase the amount of hardship above that which street trees normally face in the city. For starters, tree guards must have open sides. This is above all else a preventative measure against the soil level within the confines of the guard being raised above sidewalk level. Soil that is too high around the base of the trunk promotes negative fungal growth that could threaten the tree's health. Secondly, high-sided guards or even a concrete lip around the outside edge of the tree bed will prevent stormwater that runs across the sidewalk from entering the pit. This deprives the tree from benefitting from rainshowers runoff and keeps the trees from acting as "Green Infrastructure" and keeping our combined sewers from overloading. The image to the left illustrates an acceptable tree guard that has both open sides and allows stormwater runoff to enter the tree bed (which is mulched nicely). Tree guards are also great places to place a Curb Your Dog sign to help dogwalkers remember to pick up their animal's waste.
Next, tree guards ought to be made from a strong, durable material that will withstand many seasons of abuse from weather and city life. The tree guards should not be high enough to be a tripping hazard, nor should they have sharp edges as they are in the pedestrian right-of-way and one must always keep walkers of all ages in mind since the sidewalk is ultimately a shared space.
The image on the right is an example of what not to do to protect a tree. This type of structure is common referred to as a "tree cage" because it give the impression that one is trying to keep the tree inside as opposed to keeping the dangers out. Tree cages are extremely dangerous to street trees as they are rarely removed in time to allow the tree to grow and end up girdling the tree, a major cause of tree death in the city. TreesNY is currently saving trees that are being girdled with our Save a Tree program!
The Department of Parks and Recreation will not design/build/install a tree guard by request. Tree guards are purchased and installed by residents or business owners. Business owners are especially encouraged to install tree guards as they are a proven way to enhance pedestrian traffic around storefronts. More information about how proper tree care can improve the magnetism of your business, please visit our Trees Mean Business Page! You can find other useful tree tips here.
The following links are to manufacturers that design, build, and may also install tree guards. Thses links are not an endorsement. Trees New York does not guarantee the quality of these manufacturers work and recommends that you get several estimates and references before selecting a contractor.
ADM Landscape Corp.
A&T Iron Works, Inc.
(212) 769-CURB (2872)
Da Costa Landscaping Contractors (Installation Only)
E&J Iron Works Inc.
Guardian Gates Company Inc
Kendi Iron Works
Mozart Iron Craft Corporation (Excl. Staten Island)
Universal Steel Fabricators Inc.