Monday, August 24, 2020

When Should I Prune Trees

Tree pruning cut with a handsaw

Prevent disease, infestation, and poor health from debilitating and killing your trees. By knowing some simple pruning information and techniques, you can help your trees stay healthy and thriving for years to come.

toddsmariettatreeservices.com gathered information on reasons to prune, the best time for pruning trees, the value of pruning, how to prune branches, and when you should seek a professional tree service.

Why Are You Pruning Your Trees?

Before picking up any equipment or making any pruning cuts, you should be crystal clear about the reason for your pruning. The following are some of the reasons trees should be pruned:

  • Encourage growth in a specific direction
  • Eliminate potentially dangerous branches
  • Remove interfering branches
  • Shape your tree
  • Encourage or reduce flowering or fruiting
  • Remove suckers or water sprouts
  • Crown cleaning (removes dead, diseased, or infested wood)
  • Crown thinning (allows more light to reach inner branches)
  • Crown raising (removes lower beaches)
  • Crown reduction (for mature trees, leaves old growth while encouraging new growth)

Once you have accomplished your pruning goal, stop. Every cut you make is an open wound and potential for infection and infestation.

Note: Never make physical contact with a tree that touches live power lines. The tree may be energized and cause your electrocution. In these cases, contact your power company to either prune the tree or cut the power while pruning or have the tree pruned.

Tip: Avoid pruning activities in late summer and early fall, this is the time diseases are most active and infectious.

Pruning Deciduous Trees

Deciduous tree species are those that shed their foliage in the fall, preparing for winter dormancy. During this period of dormancy, the tree conserves energy and slows all of its functions to a slow crawl.

Pruning deciduous tree species during dormancy in late fall or early winter

Once the tree is dormant, and until bud break in early spring, it can be safely pruned for structure, shaping, safety, and encouraging vigorous, healthy new growth. Deciduous tree species include:

  • Maple
  • Oak
  • Elm
  • Beech
  • Aspen
  • Birch
  • Poplar
  • Willow

Pruning a deciduous tree during its dormancy period lowers the multiple risks of disease and pest infestations in open pruning wounds.

Pruning Evergreen Trees

Evergreen species are those that retain their foliage throughout the year. In the case of evergreens, they will shed old foliage as new foliage grows in regardless of the season. Evergreen tree species include:

  • Pine
  • Fir
  • Spruce
  • Hemlock
  • Redcedar
  • Arborvitae
  • Cypress
  • Eucalyptus
  • Yew

Except for pine tree species, evergreens should be pruned:

  • Before the emergence of new growth in early spring
  • During the period of semi dormancy in mid-summer

Use caution when pruning evergreens, some species like cypress have dead spaces behind their foliage. This is the area between the trunk and the foliage, consisting of only branches and twigs. Aggressive pruning for these species is discouraged, as it will likely leave large holes behind that will not fill in.

Pruning evergreen tree species after new growth or in mid summer

Note: Pine trees should be pruned in spring (damaged, dead, diseased, or infested branches can be pruned at any time). However, try to avoid pruning activities on pine trees in late summer and fall.

Pruning Flowering Trees

Flowering trees can be separated into two categories; One would be those that flower in the spring. The other would be those that flower in mid to late summer. Consider the following:

Trees and shrubs flowering in spring are doing so on last year’s growth. These trees and shrubs should be pruned when their flowers fade. These species include:

  • Azaleas (Rhododendron)
  • Forsythia (Forsythia x intermedia)
  • Hawthorn (Crataegus)
  • Hydrangea (Hydrangea macrophylla)
  • Magnolia (Magnolia)
Pruning flowering tree species when flowers fade or in winter

Trees and shrubs flowering in mid to late summer are doing so on the current year’s growth. These trees and shrubs should be pruned in winter or early spring. These species include:

  • Bradford Pear (Pyrus calleryana)
  • Crape Myrtle (Lagerstroemia indica)
  • Flowering Dogwood (Cornus florida)
  • Honeysuckle (Lonicera fragrantissiam)
  • Redbud (Cercis canadensis)
  • Wisteria (Wisteria species)

Pruning these species outside the timeframes described above can lead to a year without their flowering. Unseasonal pruning also exposes your tree to opportunistic diseases and insect infestation.

Pruning Fruit Trees

Your fruit trees should be pruned during dormancy, winter to early spring when foliage has fallen, and you can see the tree’s growing points (dormant buds). Think of your fruit tree as having vertical and horizontal branches.

Pruning fruit tree species in front of dormant growth buds

Pruning a vertical branch will encourage vegetative growth, creating a bushing effect. Pruning horizontal branches renews fruiting wood and thins excessive fruiting.

Pruning vertical branches opens the tree canopy to more light while pruning horizontal branches removes fruit. Horizontal branches left unpruned will bear fruit earlier with more massive crops than those that were pruned.

When preparing to prune, be aware of the following fruiting principals of your tree:

These trees fruit on last year’s shoot growth and produce abundant crops. You can safely remove half of the previous year’s growth:

  • Kiwi
  • Peach
  • Nectarine

These trees bear on spurs. You can remove up to 20% of the previous year’s growth:

  • Olive
  • Walnut
  • Fig
  • Pecan
  • Apple
  • Pear
  • Plumb
  • Apricot

Perhaps the easiest to maintain are trees bearing citrus fruit. Keep the tree skirts pruned off the ground:

  • Grapefruit
  • Orange
  • Lemon
  • Clementine
  • Pomelo

Pruning fruit-bearing trees in the summer will slow fruit ripening and expose it to sunburn. However, early summer pruning can slow the growth of overly vigorous trees that have become too large to manage.

Tip: Sun exposed branches are fruitful and will produce larger fruit. Shaded branches will eventually stop producing fruit until drastic topping occurs. If you do most of your pruning in the top portion of the tree, the lower branches will continue exposed to sunlight.

Pruning Diseased and Infested Trees

Dead, diseased, and insect-infested branches (of any tree species) can be removed at any time of the year. In fact, the harm of leaving these branches, until the right pruning season, far outweighs the potential risks of pruning them off, out of season.

If the infestation or disease symptoms are present near the branch collar or on the tree trunk, hire a professional tree service to evaluate the tree’s condition and recommend a course of treatment or preventive actions, including emergency removal.

Diseased tree with mushroom conks growing on its trunk

Note: In cases of severe infestation or infection, it is common practice to remove and destroy the tree. Thus preserving the health of your landscape and neighboring trees.

Pruning To Prevent Self-Pruning

Light deprived branches do not photosynthesize at the capacity they were intended. Over time, the tree may isolate that branch and let it go. In such scenarios, the sudden falling of a branch may occur, as the tree has self-pruned. Also known as cladoptosis, the following trees are notorious for spontaneously dropping their branches:

  • Eucalyptus
  • Aspen
  • Elm
  • Maple
  • Pecan
  • Pine
  • Poplar
  • Willow

Even providing the best care and attention possible to your trees, you may not be successful at preventing them from self-pruning. However, the following will help you slow this natural process:

  • Water your tree frequently with occasional deep waterings
  • Check the soil annually for nutrient deficiencies and its pH level
  • Prune to encourage healthy growth and remove unwanted/unneeded growth, consider crown thinning to allow more light to reach lower branches
  • Have your trees inspected annually for signs of infection and disease

Note: Even trees not known to self-prune may do so when under severe duress. Read more about cladoptosis at toddsmariettatreeservices.com/self-pruning-trees-cladoptosis/

Pruning Tools

The pruning process begins with the right tools for the job. Before starting, verify that your tools are sharp (to make clean cuts) and that they have been sanitized (to prevent transmitting disease pathogens) since their last use. The following is a list of tools to help you get your pruning job done correctly:

Pruning shears to cut stems and twigs up to three quarters of an inch
  • Hand-Held Pruning Shears (safely cuts branches up to 3/4 of an inch)
  • Loppers (safely cuts branches up to 2-1/2 inches thick)
  • Pruning Saw (capable of cutting branches up to 5 inches in diameter)
  • Pole Pruner (used to cut branches up to 1-1/4 inch thick up to 8 feet into the canopy)
  • Hedge Shears (these work well to trim evergreens)

Due to weight and the potential hazard more massive branches may pose, it is highly recommended that a professional tree service be hired to remove them.

Tip: Pruning shears and loppers come with anvil (has a straight blade using a splitting action), bypass (similar to scissors), and ratchet (like anvil, but with a locking mechanism allowing you to cut in stages) style blades.

How To Prune Tree Branches

The following will help you determine where and how to make pruning cuts:

Small Twigs and Branches – Use hand-held shears for anything up to 3/4 of an inch. You can cut these back to the main branch, or just in front of (1/4 of an inch) a dormant bud to encourage growth in the bud’s direction. All cuts should be clean and made at 45-degree angles.

Stems and Branches – Use loppers or a pole pruner to cut anything up to 2-1/2 inches. These can also be cut back to the main branch or trunk (just in front of the branch collar). If pruning out disease, make your cut 10 to 12 inches ahead of the affected area.

Large Branches – Use a saw to cut branches up to 5 inches in diameter. Due to the weight of these branches and potential for severe bark damage, make your cuts as follows:

  • Cut #1 is made under the branch about six inches ahead of the branch collar. This cut should be 1/4 of the branch’s diameter.
  • Cut #2 is made about 6 inches in front of the first cut to sever the branch from the tree.
  • Cut #3 is made just ahead of the branch collar to remove the rest of the branch.

Watch this video to see how pruning cuts are made.

Tip: When pruning any size branch back to the main branch or trunk, do not injure the branch collar. This is the tree’s mechanism used to compartmentalize the wounds left behind by pruning activities.

Note: When pruning out diseased wood, dispose of it carefully. Do not compost diseased wood or foliage, and sanitize your pruning equipment and gloves after contact with infected wood.

Tree Pruning

In this article, you discovered the best times and reasons for pruning various tree species, the value of properly pruning your trees, how to make pruning cuts, and when to call for professional help.

By pruning your trees, you can encourage vigorous growth, remove disease and infestation, and improve their health.

When you neglect to prune your trees, you encourage disease and infestation to debilitate your tree’s health, eventually leading to its death.

Sources:
mortonarb.org/trees-plants/tree-and-plant-advice/horticulture-care/pruning-evergreens
pubs.ext.vt.edu/430/430-456/430-456.html
hgic.clemson.edu/factsheet/pruning-trees/
arborday.org/trees/tips/
cesonoma.ucanr.edu/files/27164.pdf

Todd’s Marietta Tree Services

200 Cobb Pkwy N Ste 428 Marietta, GA 30062
(678) 505-0266

Originally published on: http://www.toddsmariettatreeservices.com/when-should-i-prune-trees/

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