Monday, March 28, 2016

Pruning Considerations: Shade Trees in the Landscape by Sally Blanchard

Photo by Donna Duffy
It is tough to be a shade tree here in the Front Range! With periods of drought to record precipitation, blistering heat to deep freezes, extreme winds to infestations of lethal insects, our trees need our help! Surely you’ve watered those trees during this period of warm weather and little or no snow or rain, and now it is time to look closely and see if your trees are in need of pruning. Early spring is the perfect time to accomplish this task.
Before grabbing the loppers, pole saws, or pruners, I find it helpful to follow these steps.

1. Look!  Carefully scrutinize your tree from all sides. I like to tie brightly colored ribbons or fabric strips to any limbs I am considering for removal. Dead limbs are easy; they need to go. Diseased limbs need to be cut back only as far as healthy looking wood. Limbs impeding pathways or causing safety concerns are marked next. Look to see if any limbs are crossing one another; the constant friction caused by the limbs moving in the breeze against one another will wear away the bark and open the tree to disease. Choose to keep the strongest of the limbs that provide the best structural shape to the tree.

These large crossed branches were not pruned properly years ago, allowing disease to enter the entire tree.
The tree has been removed. Photo by Sally Blanchard.

2. Back away from the tree! If your tree is sporting as many ribbons as a Maypole, definitely reconsider each marked limb again. Sometimes I even take a picture of the marked tree, print it, and use scrap paper or a marking pen to blackout the limbs I’m planning to prune. It gives me a much better idea of how the tree will look. Remember it is best for the tree to only prune what is absolutely necessary. Ideally, you are pruning limbs no larger than two inches in diameter.

3. Be safe! If you have overhead utility lines, large limbs hanging over into neighbors’ yards or over your own home, consider calling a certified professional arborist. It will cost some money but will save you, and your neighbors, so much in the long run. Also consider making that phone call if the limbs that need to be removed are larger than the two inches in diameter; tree limbs, even dead ones, are very heavy. Standing on the top of ladders or wielding heavy tools overhead is not safe, call the professionals in to help.

These cottonwoods have many dead limbs,  hang over a home, and are entangled in overhead lines.
 Photo by Sally Blanchard.

4. Prune! Finally, gather those sharpened tools on a nice sunny day. Prune only what you have marked for removal. Make proper pruning cuts above the branch collar. Wound dressings actually interfere with the actual recovery of the tree and are not recommended. Gather and properly dispose of diseased limbs; don’t leave them on the ground under your tree. 

With thoughtful pruning and year round care, your trees will reward you for years to come…unless MotherNature has other plans. Even after years of careful pruning and care and two straight years of huge freezing snowfalls on Mother’s Day, this fifty year old crabapple tree finally succumbed. But it was wonderful for 50+ years!

Photo by Sally Blanchard

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