Brochures

Trees & Shrubs

Pruning Trees & Shrubs

Pruning is a technique used to limit or train growth, improve appearance, influence flowering and fruiting and removed damaged or diseased parts.  Methods of pruning vary somewhat for trees and shrubs and the method chosen depends on the purpose of pruning.  Pruning can cause stress to plants.  Young trees and shrubs can overcome pruning stress better then older trees and shrubs.  For these reasons care should be taken to prune trees and shrubs correctly.

Pruning Methods

There are several types of pruning cuts:

Heading

is cutting of a 1 to 2 year old shoot back to a bud or smaller twig.  Usually more than one lateral branch will try to assume dominance and these will have to be removed or pruned if a single leader is to be maintained.

Tip Pruning

(type of heading) is the selective removal of several shoot terminals.  Heading and its variations increase crown and branch density.

Shearing

is the cutting of all or most new shoots to alter shape, improve appearance or limit growth on conifers or shrubs.  After shoots are pruned, many buds will produce be produced at each newly cut tip and branch density will increase.  Shrubs can be sheared back as far as illustrated.

Limbing

or stubbing is the removal of unwanted branches to the branch collar.  The correct pruning method is to make three cuts, especially on large branches.  The first cut is made on the underside of the branch– a short distance away from where the final cut us to be made.  The second cut removes the branch and the third cut removes the branch stub just above the branch collar (swollen area where branch joins main trunk).

Thinning

is the removal of lateral branches to remove crown density.  This technique can also be used for rejuvenation.  Taking out some of the oldest branches will help thin out the crown and encourage new shoot growth.

Corrective Pruning

is done to improve the health and appearance of trees damaged by weather, insects and diseases.  Branches that are not growing in an upright manner are susceptible to snow or wind damage.

Hedge Pruning

Prune so that the base of the plant is receiving ample light and water to encourage the production of new shoots.

Pruning Tools

Equipment used for pruning include secateurs, long-handled shears, hedge shears, pole pruners, pruning knives, pruning saws.While pruning is often used to remove insect and diseased portions of the tree, it can also place a tree under stress and provide wounds suitable for insect and disease entry, especially when a tree has been severely pruned.  Detailed manuals are available that provide a thorough explanation of pruning techniques.

Pruning Schedule

The time of year to prune trees and shrubs depends on the species, its condition and the purpose of pruning.  In most cases, corrective pruning of dead or weakened branches can be done at any time because it will have little effect on the tree’s growth. Removal of one or two small branches can also be done in the late fall or early winter when leaves have dropped.  This prevents excessive bleeding and the wounds will heal quickly when growth begins in the spring.  Pinching, tip pruning and shearing should be done when the shoots are actively growing in the late spring and early summer.  In the case of coniferous trees, pruning should be completed before new shoots have hardened off.  Pinching, tip pruning and shearing at this time will effectively control growth and maintain size.

 

Timing

Plant Species

Early Spring

Ash, Oak, Caragana, Poplar, Willow, Olive

Mid Summer

Maple & Birch

(First two weeks of July ONLY)

After Flowering

*see below

Mountain Ash, Hawthorne, Chokecherry, Crabapple, Apple, Mayday, Lilac, Plum

Spring & Summer

Spruce, Pine, Juniper, Cedar

After Flowering

(flowers on last years growth)

Lilac, Nanking Cherry, some Spirea

Fall or Early Spring to Shape

(flowers on new growth)

Shrub Roses (most), tea roses, Caragana, Potentilla, Dogwood, Mockorange, Spirea, Sandcherry

October to March

Prohibited April1 to September 30

Elm

 

* These trees tend to remain small and don’t usually require much pruning. Pruning after flowering will limit fruit production