Northern Nevada gardening and landscaping: Prune for tree health, please | Carson City Nevada News
I recently discovered a poor, pathetic, ornamental crab apple tree. All the branches and the top had been mercilessly sawed off and left disfigured stumps. I hadn’t seen a so-called editing job in a while. It was bad enough that the branches were ruined, but the entire main trunk of the tree was also cut off.
Why do people circumcise so drastically? Some believe that a tree gets too tall and unsafe. Some think this is how a tree should be pruned after another tree has been pruned. Others may like the quick growth of small twigs that can emerge after a heavy cut that gives a lollipop look. To some, it seems easier and faster to prune everything at once than to selectively prune just 25 percent of the growth per year, which requires more skill and care.
Trees should not be crowned or pruned in this way, as doing so removes too much of the canopy to adequately photosynthesize (produce food) the roots, leaves, and the rest of the tree. Removing the crown exposes the entire tree to suntan damage, a definite problem in northern Nevada.
All open wounds are portals for the infection of diseases and at the same time give off chemical signals to insects that say, “Come on, get me. I am weak and vulnerable. “In the long term, the wounds are unlikely to form a callus, leaving the tree vulnerable to disease and insect attack for years (if it survives that long).
Although this radical pruning can encourage many new sprouts, they are weakly tied to the parent branch and become dangerous. Tree death can be caused by this type of pruning. Aside from harming tree health, this type of mutilation is ugly!
Sometimes for fruit trees, mainly in commercial orchards, a heavier pruning is acceptable to maximize fruit production. With this type of pruning, trees can be replaced more often than in a domestic landscape. Personally, I don’t want to look at such a tree in my garden. It hurts my sense of what is good for a tree and my sense of visual aesthetics.
To prune properly, step back and evaluate the shape of the tree. Remove branches that are crossing, rubbing, damaged, aimed at the center of the tree, or dead. Prune to improve not only the beauty of your tree but its health as well. Oregon State University offers an informative online resource here.
– JoAnne Skelly is Associate Professor & Extension Educator Emerita at the University of Nevada Cooperative Extension. She can be reached at [email protected]