Pruning
Why Prune
Pruning, although sounding backwards and harmful for the tree, is actually vital for a tree's growth and survival when done correctly. Pruning can prevent a tree's harmful growth patterns, like codominant leaders (multiple leading branches as depicted in the infographic), that can appear in a tree's early life.
When to Prune
First and foremost, young trees should not be pruned until a year after planting with the exception of removing dead or damaged branches. Additionally, pruning should be avoided until wintertime to combat pests and diseases like Oak Wilt, Dutch Elm Disease, and Emerald Ash Borer. Knowing what tree species, you have is important to knowing when it's safe to prune.
Hard do not prune dates:
- Elm's: April 15th (late spring)-late July or fall to prevent the spread of Dutch Elm Disease
- Oak's: April-October to prevent the spread of Oak wilt
- Ash's: May 1st-September 30th to prevent the spread of Emerald Ash Borer
How to Prune
There are two main kinds of pruning cuts, a heading cut and a thinning cut. A heading cut is used to encourage the growth in the buds or branches near the cut to increase fullness. A thinning cut is used to cut back a whole branch to encourage the closest bud to grow, this type is also used to change growth directions.
For a visual example of these cuts be sure to check out the attached infographic. Additionally take a look at the UMN Pruning Trees and Shrubs page as they have an excellent video tutorial.
What to Prune
Pruning trees can seem daunting and high stakes but keeping these concepts in mind can simplify the act. Prune injured or dead branches to avoid disease for your tree's and other residents' tree's. If there are branches that look as though overtime they will collide or rub together, remove one. Increase air flow for your tree by removing growth that points towards the trunk of the tree. Remove multiple leaders or narrow "V" joints to prevent your tree from splitting down the middle overtime. Waterspouts and suckers should be removed.