Overview and schedule of general maintenance activities for tree trenches and tree boxes
Link to this table

First Year of Operation
Activity Frequency Time period Level of effort O&M benefita
Check that there is no ponding within the box or trench. At least twice after storm events > 0.5 inches Within the first 6 months 1-2 hours 1,5
Check for evidence of clogging in the media. At least twice after storm events > 0.5 inches Within the first 6 months 1-2 hours 1
Supplemental watering, during drier periods, particularly if keeping stormwater offline trees are established. 1/week initially During first two months of the growing season 1-2 hours 2,3,4,5,6
As needed First growing season 1-2 hours 2,3,4,5,6
Remove any weeds present As needed First growing season 1-2 hours 2,3,4,5,6
Remove any trash or debris As needed First growing season 1-2 hours 1,2,3,4,5,6
Add mulch if layer is less than 3 inchesb As needed First growing season 1-2 hours 4,5
Clean root collar Annually During growing season 1-2 hours 1
Remove stakes As needed End of growing season 1-2 hours 5
Inspect tree health Biannually and after large storms First growing season 1-2 hours 1,2,5,6
After First Year of Operation
Activity Frequency Time period Level of effort O&M benefita
Check that there is no ponding within the box or trench. Biannually Any time when ground is not frozen 1-2 hours 1,5
Check for evidence of clogging Biannually In spring and fall 1-2 1
Supplemental watering during drier periods As needed or when soil is dry 3 inches below the surface Dry periods until roots are established 1-2 hours 2,3,4,5,6
Remove any weeds present As needed During growing season 1-2 hours 2,3,4,5,6
Remove any trash or debris As needed Any time 1-2 hours 1,2,3,4,5,6
Add mulch if layer is less than 3 inches Annually During growing season 1-2 hours 4,5
Remove stakes (if still present) Once End of second growing season 1-2 hours 5
Prune excess growth
  • Once in year 2 or 3,
  • Every three years between years 4-10,
  • Every five years as needed after 10 years
End of winter or early spring 1-2 hours 2,5,6
Inspect tree health and safety Biannually and after large storms During growing season 1-2 hours 1,2,5,6
After 5+ Years of Operation (non-routine maintenance)
Activity Frequency Time period Level of effort O&M benefita
After long term operation of the practice, some occasional and infrequent maintenance activities might be required, such as tree or media replacement. As needed As needed Could be significant depending on the activity 1,2,3,4,5,6

aKey to Maintenance Benefits:

  1. Proper stormwater flow and infiltration
  2. Creation and maintenance of wildlife habitat
  3. Creation and maintenance of pollinator habitat
  4. Nutrient cycling and storage
  5. Aesthetics and public enjoyment
  6. Carbon sequestration
bNote that many practitioners are minimizing the use of mulch or using alternatives to mulch to control weeds. Using mulch can cause clogging of inlet, outlet, and bypass pipes, and can introduce invasive species such as jump worms. Alternatives to mulch include ground vegetation such as clover or sedges, or arranging plantings in more dense configurations so as to minimize use of mulch.

This page was last edited on 5 August 2022, at 00:24.