Adapted from www.organicgardening.com

This view up the trunk of a large yellow poplar (Liriodendron tulipifera) shows one reason why trimming in winter is advisable with the specie: you can see limbs and crown when foliage is absent.
PHOTO COURTESY OF Brian Lockhart , USDA Forest Service, www.forestryimages.org

The first day of autumn is Sept. 23, which means tree trimming season is right around the corner. Fall is prime time for pruning flowering trees. Most are ready for pruning 30 days after blooms and fruit are gone.

A book like Rodale?EUR??,,????'???s Illustrated Encyclopedia of Gardening and Landscaping Techniques or the Sunset Garden Book can help you with species-specific tips for trimming and care.

 

Whitmer Wright prunes with a power saw in the Heppner Ranger District, Umatilla National Forest, Ore. The chance of insects invading wounds is greatly reduced when nighttime temperatures fall below freezing.
PHOTO COURTESY OF Dave Powell, USDA Forest Service, www.forestryimages.org

What to Prune in Winter

Pruning in winter?EUR??,,????'??+during the dormant season?EUR??,,????'??+invigorates many trees and shrubs because it leaves the plants with extra root and energy reserves that will support new growth on the remaining branches. Dormant-season pruning is good for you, too, because you can see the branches more clearly without leaves in the way. And it gives you a reason to go outside on mild winter days.

Here is a very partial list of shrubs and trees you can prune from winter until the long days of spring start sap flowing again. Below is a short list of trees not to prune during winter.

Schoolchildren taste sap from a sugar maple at the Touch of Nature Environmental Center near Carbondale, Ill. As with maples, dogwoods, elms (and several other species) ?EUR??,,????'??bleed?EUR??,,????'?? sap during the winter and should be pruned during summer or fall.
PHOTO COURTESY OF Southern Illinois University

Trees to Prune in Winter

• Bradford and Callory pears
• crabapples
• poplar
• spruce
• junipers
• sumacs
• bald cypress
• cherries
• plums
• honey locust

As with other flowering trees, fruit trees like this apple should be pruned in late autumn before new foliage appears. This is a backyard amateur, of course. Professional trimmers wear hats, gloves, eye protection and other safety gear when tackling trees.
PHOTO COURTESY OF Sven Rinke, Duke University

Don?EUR??,,????'???t Prune During Winter

Some trees ?EUR??,,????'??bleed?EUR??,,????'?? or ooze sap when pruned in late winter or early spring. While oozing sap is not dangerous to the tree, it can make a sticky, dirty mess, especially on parked cars. Prune these trees in summer or fall:

The Right Cuts

• Remove dead or dying branches.
• Prune out diseased limbs right away. Be sure to cut well below the diseased areas, and don?EUR??,,????'???t prune when the plants are wet (water can spread disease). If you prefer to be extra cautious, rinse your tools with a solution of 10 percent bleach in water.
• Cut back branches that have grown over where you walk or mow so they don?EUR??,,????'???t break off.
• Where you see two branches crossing, prune off the smaller one.
• Thin branches judiciously to allow sunlight and air into the center of trees and shrubs.

Winter Tree Care Advice Summary

From www.treesaregood.com:

A properly pruned limb is cut flush with the trunk of a tree. This is not only the best looking way to trim, it encourages the formation of healthy woundwood.
PHOTO COURTESY OF Joseph O'Brien, USDA

Winter brings frigid temperatures, icy winds and plenty of snow. Just as people battle Mother Nature at this time of the year, so do trees, with one major exception: trees can?EUR??,,????'???t avoid exposure to the elements.

?EUR??,,????'??While your trees seem to be in a state of hibernation in the winter, exposure to the tough conditions can cause them major stress,?EUR??,,????'?? said Jim Skiera, Executive Director of the International Society of Arboriculture (ISA). ?EUR??,,????'??Minimize that stress by helping your trees through the cold months, a little at a time. If you take care of your trees in the winter, you?EUR??,,????'???ll be rewarded in the spring.?EUR??,,????'??

• Put composted organic mulch under your tree in the fall or early winter to help retain water and reduce temperature extremes. A thin layer of mulch will act like a blanket and give the tree?EUR??,,????'???s roots a little extra winter protection.
• Give your trees a drink. Winter droughts require watering as much as summer droughts. If temperatures permit, an occasional watering during the winter on young trees can be a life saver. But be sure to water only when soil and trees are cool but not frozen.
• Prune your trees. Winter is actually one of the best times to prune because it is easier to see the structure of trees without their leaves. But limit pruning to deadwood and poorly placed branches in order to save as many living branches as possible.
• Prevent mechanical injuries. Branch breakage or splitting can be caused by ice and snow accumulation, or chewing and rubbing by animals. Prevent problems from occurring on young trees by wrapping the base of trees in a hard, plastic guard or a metal hardware cloth. Wrapping trees with burlap or plastic cloth also can prevent temperature damage. Just remember to remove the wraps and guards in the spring to prevent damage when the tree begins to grow.