This article was posted at "Gardensalive.com",
This all began began with a phone call on the show a while back, when our listener asked the dreaded 'follow-up' question, which is always like the teenagers in the slasher movie deciding to go down and see what's making that strange noise in the basement. Like them, I should have instead run screaming from the house.
She asked what time of year would be best to prune a Bradford pear they had planted under power lines (apparently not expecting it, like other trees, to grow any taller). I said 'dead of winter', which is technically correct if you don't include the power lines. When you DO include them, the 'dead' part becomes the accurate word in my phrase. The correct answer is of course 'never'. "Call the power company and let people who are trained in avoiding electrocution handle it" is what I should have said.
But I didn't. And so my penance was to say fourteen Hail Mary's, six Our Father's, a Perfect Act of Contrition and have someone on the show who knew what they talking about. That wound up being Rick Johnstone, president of Integrated Vegetation Management Partners, Inc. in Newark, Delaware and a Past president of the Utility Arborist Association. Here's his/our Top Ten Tips for Proper Tree Trimming Safety:
- Observe the ten-foot rule. Don't attempt to work on trees that are within ten feet of any kind of overhead wires. This distance insures that you won't touch any wires while you're on your way down to break your neck.
- Call the electric utility instead. You don't have to touch any wires personally to headline a big story in your local paper. Just touching a branch that's touching a wire can cause fatal injury, as the voltage on a typical overhead power line can be a hundred times greater than your indoor household current. Here's some more detail on distances and other safety issues.
- Do call if branches are in or approaching the lines—especially the branches of fast-growing trees, as these are often the weakest and most prone to breaking. Don't ignore a potential problem; if you do, it'll be your fault when everybody has to huddle for days in the cold and dark after the ice storm.
- Plant the right trees to begin with. Here's a link to an article from Tennessee that Rick Johnstone especially likes, naming the best trees and big shrubs to install near power lines.
- When doing any pruning, work only on a steady, level surface. Untrained individuals who try to prune big trees from a ladder often end up toast—and that's without impacting any power lines. If you can't do the work safely, easily and with your feet on terrafirma, call a pro. The International Society of Arboriculture (ISA) is the organization that certifies arborists as being well trained. (When people say they're a "certified arborist", ISA is the certifying body.) The Tree Care Industry Association (TCIA) accredits tree-care companies
- For work that you can do safely, don't remove large branches all at once. It may be funny in a cartoon, but it's no joke when a 60-pound piece of wood swings around and knocks you for a loop. Large branches should be removed in small, easy to handle sections. (My own rule of thumb is to cut sections that are already perfect wood-stove or fireplace size without additional cutting.)
- For the long-term health of the tree, always remove dead or heavily diseased limbs (or have them removed) as soon as possible. Don't worry about seasonality.
- Never cut a branch flush to the trunk of a tree. Look carefully where the branch meets the tree; you'll see a little 'collar' there. That collar should still be attached to the tree after you take the branch off.
- Don't seal any pruning cuts or other wounds. Like humans, trees are very good at sealing over injuries with their own form of scar tissue; spreading anything overtop of a wound will only interfere with this natural process.
- Never 'top' a tree. Many homeowners put trees in the ground without any thought as to how high they'll eventually get. Experts can lower the height of some deciduous trees without damage or disfigurement, but no one can do it on evergreens with pointy tips. And you can't give ANY tree a straight across 'crew cut' and expect it to do anything than look really ugly for a few years and then die.