Tree Pruning Tip Sheet

Download 222K pdf file ("tree_pruning_tips_sheet2.pdf")PDF
     Subscribe to our free E-Newsletter, "Agri-News" (formerly RTW This Week)Agri-News
This Week
For beginners doing pruning in their yards.

For any large pruning please contact professional certified arborist.

When to prune?
  • Coniferous trees, like spruce or pine, can be pruned any time of year. For most trees, the best is time from March to mid-April or during the winter
  • Birch and Maple – prune ONLY during the growing season – June and July – leaves must be fully developed
  • Elm trees – DO NOT prune from April 1 till October 1
  • Hardwood trees, like aspen or ash, and shrubs without showy flowers, prune in the dormant season
  • to easily visualize the structure of the tree,
  • to maximize wound closure in the growing season after pruning,
  • to reduce the chance of transmitting disease, and
  • to discourage excessive sap flow from wounds
Why prune trees?
  • To remove “3D- Dead, Diseased or storm-Damaged” branches
  • To thin the crown to permit new growth and better air circulation
  • To reduce the height of a tree or to remove obstructing lower branches
  • To shape a tree for design purposes
  • To reduce potential fire hazards
  • To encourage flowering, to promote fruit production
  • To address safety issues for people or property

How much to prune?
  • Every time you prune a tree, it stresses the tree and increases vulnerability
  • Pruning increases the opportunity for insects and diseases to invade trees
  • Generally speaking, prune no more than 25 % of living branches
  • The amount of live tissue that should be removed depends on the tree size, species, and age, as well as the pruning objectives
Basic principles of pruning
  • Visualize the shape of the plant at maturity
  • how the tree will look like after pruning
  • Remove dead, damaged and diseased wood
  • Select the key branches or main stems that you want to keep
  • Remove weak crotches, crossed branches, suckers and watersprouts (new branches growing near bottom of the tree)
  • Cut back to branch collar to leave the smallest wound possible
  • Remember that more is not always better
  • you can always prune next year
Pruning techniques
  • Cleaning is the removal of dead, dying, diseased, crowded, weakly attached, and low-vigor branches from the crown of a tree.
  • Crown Thinning is the selective removal of branches to increase light penetration and air movement through the crown (the branches and leaves extending from the trunk or main stems). Thinning opens the foliage of a tree, reduces weight on heavy limbs, and helps retain the tree’s natural shape.
  • Raising removes the lower branches from a tree in order to provide clearance for buildings, vehicles, pedestrians, and vistas.
  • Reduction reduces the size of a tree, often for clearance for utility lines.

Pruning Tools
  • Keep pruning equipment (pruning shears, loppers, saws, etc.) sharp and clean.
  • You get what you pay for, so cheaper tools....usually are !!!!
  • Before you cut, dip your pruner for a few seconds in bleach.
  • After pruning, put the tools under running water for 10 minutes and thoroughly dry.
  • Dry tools after clean up – don’t let them rust.
  • Clean up tools after you finish your work.
  • Buy only the tools that you really need - pruners, rounding saw, loopers, sheers, secateurs
Pruning Shrubs
  • Shrubs that bloom before June 20 should be pruned immediately after the bloom period.
  • Shrubs that bloom after June 20 should be pruned in the dormant season or just before growth in spring.
  • Not all shrubs needs to be pruned, not every year and not severely.
  • Many flowering trees/shrubs (eg crabapple, hawthorn, pin cherry, chokecherry, etc) are susceptible to fire blight and black knot fungus, and pruning can spread these diseases.
Pruning Roses
  • In the wild, roses produce strong new shoots from near the base of the plant each season.
  • Prune during the winter – March/April just before the season starts.
  • Deadhead during the summer – prune back to a five leaflet leaf.
  • Cut above an outward pointing bud to encourage an open center.
  • Cut back into healthy wood.
  • Cut any diseased or damaged branch.
  • Remove all thin, weak canes that are smaller in diameter than a pencil .
  • Get pruning safety training, available at many arborists.
  • Have an emergency plan in place in case an incident occurs.
  • Wear eye protection at all times.
  • Wear a hard hat and steel toed boots.
  • Wear leather or other appropriate gloves.
  • Do not use axes or hatchets—use proper pruning equipment.
  • If you use power tools, please follow their safety procedures.
  • For beginners, do not climb trees.
Myths about Pruning
(and the truth)
  1. Pruning is difficult – pruning is not complicated, but it is hard work
  2. Plants will die if they are pruned wrong time of year - not true
  3. All pruning must be done during the winter - with a few exceptions, you can prune year-round
  4. Removing and pruning trees is a crime against nature - not true
  5. Most trees need pruning - this is not true, unless there is a valid reason to prune a tree
  6. Hedge shears are all you need to prune shrubs - shrubs require more than hedge shears, they require proper pruning
  7. Anybody with a pick-up truck, chainsaw, and pruners is an expert - use people with knowledge and expertise in this area
  8. All cuts must be treated with paint - not true
Share via
For more information about the content of this document, contact Toso Bozic.
This document is maintained by Brenda McLellan.
This information published to the web on June 11, 2015.
Last Reviewed/Revised on April 5, 2018.