Tree grilles and guards

Tree grilles and guards protect the root system from trampling while still letting water and air reach the soil freely. They come in square and round shapes, sized to suit the trunk diameter and the surroundings. They are an essential part of street tree planting in places with heavy pedestrian traffic. Protecting street trees is a separate section of the street furniture range, developed alongside our benches and litter bins.

Made of cast iron or galvanised steel, the grilles have a high load-bearing capacity, so the surface stays safe and comfortable for pedestrians, pushchairs and cyclists. Their modular design makes it easy to remove them temporarily during tree care work without replacing the whole unit.

The size of the central opening must allow for the final girth of the mature tree, not just the current diameter of the young tree. If the opening is too tight, over time it starts to cut into the bark and restricts the flow of water and nutrients. In extreme cases, this can weaken or even kill the tree.

The load-bearing capacity a grille needs depends on how much traffic it will carry. A grille on a busy city-centre footway, regularly crossed by service carts and bicycles, needs a higher load class than one in a quiet estate park visited mainly by pedestrians.

Cast iron is heavier and more expensive than galvanised steel, but it resists corrosion better during long-term contact with the damp soil around the trunk. It is a popular choice for projects with a longer service life, where the future cost of replacing a unit would be greater than the difference in purchase price.

The perforations in the grille are designed to let rainwater drain freely into the soil while stopping leaves and litter from collecting in the openings. Openings that are too small restrict water infiltration, while openings that are too large create a trip hazard for pedestrians, especially those wearing heels.

When streets and city squares are regenerated, tree grilles are increasingly treated as part of a consistent public space design. Their colour and style are matched to the other street furniture, such as benches, lamp posts and litter bins, instead of being a random, makeshift addition to the pavement.

Tree grilles and guards are often ordered together as a matching set that protects the tree at both soil level and around the trunk. Used together, they protect young trees better than either element would on its own.