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 in 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 public safety along roads and within parks. 

Why wait to prune until November?

• Pruning during the fall and winter 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 late 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 young trees 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 continue until the tree is 15-20 years old 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:

• Find out more and watch demonstrations on how to prune young trees on the Minnesota DNR's website.
• Find a company with an ISA Certified Arborist to assess your trees on the International Society of Arboriculture's website.