When it’s time to prune your favorite shrub or tree — deciduous trees should be pruned in winter, while evergreen trees are best pruned after flowering — it’s important to do so properly so you can ensure a healthy, attractive plant. And if you’ve looked into pruning, you’ve probably heard terms like “crown raising,” “heading” or “thinning,” among others, being used to describe the type of pruning method needed. But what do these words all mean?

Why Is Pruning Important?

Before you head outdoors and start cutting away at the shrubs and trees in your garden, or consider forgoing pruning, let’s take a few moments to understand why pruning is important.

It encourages strong branching and removes weak or crossing branches.

It eliminates dead or diseased wood.

It stimulates new, attractive growth.

It helps to improve resistance to windy conditions.

It promotes good air circulation, which decreases the incidence of fungal disease.

In short, proper pruning practices are an important part of maintaining woody plants like trees and shrubs.

Pruning Terms To Know

Crown:  The upper part of the tree, made up of the branches, stems and leaves — also referred to as the “canopy.”

Crown Cleaning:  Pruning away dead or diseased branches and stems. This also includes the removal of any “stubs,” which are the dead base of a branch that wasn’t pruned back to the trunk.

Crown Raising:  Removing lower branches back to the trunk to elevate the crown of a tree or shrub. Crown raising is often done to provide clearance for pedestrians, cars or anything else that might be under the tree.

Crown Reduction: The removal of a percentage of the outer part of a tree or shrub by pruning back the leaves, stems and branches. This is often done to prevent wind damage or a tree from blowing over.

Crown Thinning:  Involves the removal of select interior branches to improve air flow and reduce the weight of the tree. The overall shape and size of the tree remains the same when this type of pruning is done.

Heading back:  Pruning back branches up to half of their length to reduce outward growth. This is done with shrubs to reduce their size while promoting a natural shape. Heading back is also done to long, overhanging branches on trees to reduce the weight at the ends and to keep them from touching buildings or other structures.

Root prune: Roots are pruned, and a root barrier often put in place, when they cause problems with foundations, sidewalks or walls through cracks or uplifting. It’s important to have an arborist (a professional tree cutter) do this work, since removing too many roots can kill your tree.

Shearing: This type of pruning is done to shrubs using hedge trimmers to remove a percentage of their outer growth. It is commonly used to create formal hedges or topiary shapes.

Structural Pruning: This type of pruning is usually done on young trees and focuses on creating a strong form by selecting the branches that will give the tree a nice shape, along with strength to withstand windy conditions. Branches that are growing in the wrong direction or have a weak attachment to the trunk are removed.

Topping: This is the removal of the top part of a tree, often done to improve a view or keep a tree from growing into power lines. This type of pruning should never be done, for a number of reasons: It leaves the top of the tree susceptible to sunburn and insect infestations, while the new branches that grow back have weak attachment to the tree and are more prone to breakage and are hazardous. Topping also makes the tree grow faster in its attempt to replace the lost foliage, creating a vicious cycle.

Crown reduction can be done by a professional for trees that need their height reduced. The best option is to prevent the problem from occurring by considering the mature height of trees before planting. The good news is that if you have a tree that has been topped, it can be restored by an arborist by a process known as “crown restoration.”

Pruning Tools

Let’s take a look at the common tools used.

Chainsaw: This is a power saw is used to prune larger branches that other pruning tools can’t. They come in different blade sizes and power levels.

Hand Pruners: This is the smallest pruning tool, used to make cuts that are under 1 inch in diameter. While there are different types of these smaller pruning tools, “bypass pruners” are most recommended — made of two curved blades that bypass each other, creating a clean cut. They are used for making heading and thinning cuts.

Hedge Trimmer: This pruning tool comes in two different forms: manual and power. The manual hedge trimmer looks like giant scissors and is best used to create formal hedges, cutting the small, twiggy growth that makes up the outer part of shrubs. The power version looks very different, with oscillating blades that shear back outer growth easily. Hedge trimmers are used for shearing cuts.

Loppers: The large bypass blades of this garden tool cut through branches that are three-quarters of an inch to 2 inches in diameter. They have long handles, which enable the user to prune tree branches and also reach into the interior of shrubs. A pair of loppers is a great tool for pruning rose bushes.

Pole pruner: Pole pruners are for making pruning cuts up into the canopy of trees while allowing you to keep your feet on the ground. There are different types, which include manual and power saws mounted at the end of an adjustable pole, often reaching up to 16 feet in length. Manual pole pruners have a pruning saw at the end as well as a bypass pruner that is operated by pulling a cord. The power option is a mini chainsaw that can reach up to prune larger branches.

Pruning Saw: A manual saw that is perfect for cutting through branches that are over 1½ inches in diameter. Pruning saws are the tool of choice for limbs too big for loppers. The blade is either straight or slightly curved, sometimes folding into the handle when not in use. With some effort, it will cut through most small to medium branches up to 6 inches in diameter.