Tree Pruning

In an effort to proactively care for the city’s trees, staff will begin pruning in designated districts of road right-of-ways and city parks this November. Work will continue until early March and will focus on removing dead, dying, and low hanging branches to improve the health and condition of the trees as well as to ensure the safety of the public along roads and within parks. If your home is in the street pruning district, you will get a letter in the mail in October. 

Why wait to prune in November?

  • Waiting to prune will reduce the risk of introducing insects and disease into the community’s trees. You might move around actively flying insects like emerald ash borer with your branches and brush unless you wait until fall. Oak wilt can be introduced into a healthy oak from April through October when a pruning cut is made during that time period.
  • Summer is the time when trees capture and store energy. Leaves are the tree’s food factories, and if you cut them off while they are busy capturing energy you are depriving the tree the ability to store those nutrients. It is better to wait until the energy has moved from the leaves into the branches, stem, and roots after the leaves have dropped.

Why prune?

  • Aside from aesthetic and safety concerns, pruning establishes strong branch structure.
  • Did you have large branches tear out of your trees during the heavy rain and wind storms this summer? Certified arborists usually call these “predictable failures” because they could have often been avoided if the tree had been pruned earlier in its life. 
  • Developmental pruning should start the year after the tree is planted, and aims to train the tree to have one central leader branch. It also keeps pruning cuts small so wood rot doesn’t establish in the tree.

What to do:

Red maple with weak point
This red maple has been in the landscape for 10 years without formative pruning. Notice the weak point (crack) in the tree where the two branches may split in the future.
Basswood pruned along a road edge
This basswood along a road edge was pruned to raise its canopy.
Ash tree that split
This ash tree grew from a sprout and had three stems. Over time, decay formed and the tree split. If this tree had been pruned to a single stem, it may still be standing today.