Street trees do quiet, important work. They shade sidewalks in summer, absorb stormwater, clean the air, provide homes for birds, and make neighborhoods more beautiful. In cities like Boston, many of these trees grow in small squares of soil cut into the sidewalk, known as tree pits.
Winter is hard on street trees. Road salt, plowed snow, compacted soil, litter, and dog waste all pile up around their roots. As spring arrives, neighbors can give these trees a helping hand with a little gentle care. This guide covers what you can do, what to avoid, and when to leave the work to professionals.
Why Tree Pits Need Attention
Street trees often grow in tough conditions. Their roots are squeezed by pavement, their soil gets packed down by foot traffic, and winter salt can damage roots and leaves. After a long winter, tree pits may be:
- Covered in sand and salt residue
- Littered with trash, cigarette butts, and plastic
- Compacted so tightly that water runs off instead of soaking in
- Filled with weeds as soon as the weather warms
A cared-for tree pit lets water and air reach the roots, which helps trees stay healthy and live longer.
Before You Start: Check the Rules
Most street trees are owned and maintained by the city or town. Many cities welcome residents caring for tree pits, but some have specific guidelines. Check your city’s official website, ask through 311, or contact your parks or forestry department about:
- Whether residents can loosen soil, mulch, or plant in tree pits
- Any restrictions on fencing or edging around tree pits
- Programs that support residents who adopt street trees
Never prune, cut, or remove a street tree or its branches yourself. That work belongs to trained city crews or licensed arborists.
Step-by-Step Spring Tree Pit Care
- Wear gloves. Tree pits can contain broken glass, sharp litter, and pet waste.
- Remove trash. Pick up litter, plastic bags, and debris. Leave needles or syringes alone and report them through 311.
- Clear excess sand. Gently sweep away heavy layers of winter sand from the soil surface.
- Loosen the top layer of soil. If allowed, use a hand cultivator to gently loosen only the top inch or two of soil, staying well away from the trunk. Avoid digging deep, which can damage roots.
- Pull weeds by hand. Remove weeds before they take hold, being careful not to disturb roots.
- Water if dry. Spring rain usually helps, but young trees benefit from deep watering during dry stretches.
- Add mulch. Spread a thin layer of mulch, about two to three inches deep, over the soil.
The Right Way to Mulch
Mulch helps hold moisture, keeps soil cooler, and reduces weeds. But mulch done wrong can harm trees.
- Keep mulch a few inches away from the trunk. Mulch piled against bark can cause rot and invite pests.
- Avoid “mulch volcanoes,” the tall cones of mulch sometimes seen around tree trunks.
- Use shredded wood or bark mulch rather than dyed mulches.
- Spread mulch evenly in a flat layer, like a doughnut, not a mountain.
What About Planting Flowers?
Some cities allow residents to plant small flowers in tree pits, while others discourage it. If planting is permitted:
- Choose small annuals or shallow-rooted perennials that do not compete heavily with the tree.
- Avoid digging deep holes or adding large amounts of new soil, which can smother roots.
- Do not raise the soil level against the trunk.
- Skip bulbs that require deep digging near roots.
- Water plants gently, which also helps the tree.
Protecting Trees From Damage
Beyond cleanup, neighbors can help protect street trees throughout the year:
- Do not lock bikes to young trees.
- Avoid piling salty snow into tree pits during winter, when possible.
- Keep car doors and bumpers from scraping trunks when parking.
- Encourage dog owners to keep pets out of tree pits and clean up after them.
- Avoid nailing signs or attaching decorations to trees.
When to Call the City
Some tree issues need professional attention. Report them through 311 or your parks or forestry department:
- Large broken or hanging branches
- Trees leaning dangerously or with cracks in the trunk
- Signs of disease, such as large areas of peeling bark or many dead branches
- Roots lifting sidewalks severely
- Empty tree pits where a tree has died or been removed, which may qualify for replanting
- Requests for new street trees, which many cities accept from residents
Organizing a Tree Care Morning
Caring for one tree pit is easy. Caring for every tree on the block is even better with neighbors. A simple tree care morning might look like:
- Confirm city guidelines for tree pit care.
- Walk the block and count the tree pits.
- Gather gloves, hand tools, trash bags, buckets, and mulch.
- Pair up volunteers and assign trees.
- Spend about fifteen to twenty minutes per tree pit.
- Report any problems you notice.
- Take before-and-after photos to celebrate the work.
Many neighbors find they become attached to “their” tree and keep checking on it all season.
Spring Tree Pit Checklist
- Check city guidelines before working on street trees.
- Wear gloves and remove litter safely.
- Loosen only the top layer of soil, if allowed.
- Mulch in a flat layer, away from the trunk.
- Water during dry spells.
- Report damage or hazards through 311.
Quick check: What is the right way to apply mulch around a street tree?
- Spread a flat layer a few inches deep, kept away from the trunk
- Pile it high against the trunk to keep it warm
- Use as much as possible to cover all the roots completely
Show answer
A. A flat layer kept away from the trunk holds moisture without causing rot or pest problems.