"I think people are afraid of pruning, especially pruning trees, because they're afraid they'll make a permanent change that they don't like," says Charles Tubesing, chief horticulturist at the Holden Arboretum in Kirtland, Ohio.
Or, as "The Hillier Gardener's Guide to Trees and Shrubs" puts it:
"Proper pruning is one of the best things you can do to help keep a tree healthy. Conversely, bad pruning is one of the worst things that you can do to a tree."
In other words, before reaching for those sharp shears, saw and towering ladder, it's a good idea to know what you're doing.
When to prune, and how much depends on the type of tree or shrub, particularly flowering trees and shrubs.
It isn't always necessary to prune every tree on your property, says Tubesing. Mother Nature took care of that chore for years without any help from humans. With some trees, it's OK to leave well enough alone.
But there are reasons to regularly prune landscape botanicals, especially deciduous, the primary reason being when a tree has grown so expansive that it blocks your view through the window. Or if the tree not only is filling up your yard, but spreading into your neighbors', and the neighbors aren't happy about it.
It's also smart to lop off damaged, diseased and dead branches before the problem spreads and destroys the entire growth (this should be done any time of year).
Pruning also makes trees prettier by encouraging vigorous growth.
Generally, the time to prune most trees is late fall to early winter, say experts. With the leaves gone and the skeleton of the tree fully exposed, it's easier to see damage and where corrective pruning is needed. Without leaves, it is more convenient to get at branches that overlap your roof, or are otherwise poking toward places where they shouldn't.
But because pruning can stimulate new growth, it's best not to prune too early in the fall. New growth might not harden off before winter.
"You can also prune during mild spells during the winter," says Tubesing. "It's much easier to see the structure of the tree then."
It's good to prune early-flowering shrubs, such as rhododendrons and azaleas, immediately after they have finished blooming because that's when they set the buds that will bloom next spring, says Thomas Mugridge, general manager of Forest City Tree Protection Co., a family-owned business in South Euclid, Ohio. So if you haven't already pruned flowering shrubs, you might want to hold off.
The exception is if your flowering shrub has grown out of control and you don't want it to get any larger, adds Mugridge, who is the incoming president of the American Society of Consulting Arborists and chairman of its membership committee.
By pruning now, you might sacrifice some of the buds that would have bloomed next spring, but whatever you haven't cut off will still flower.
Late-summer blooming shrubs, such as rose of Sharon, bloom on new growth from that spring, Mugridge says. So prune them anytime after they flower in late summer right up until the following spring without sacrificing any flowers. Included in this category would be butterfly bush (buddleia).
"I prune mine down every spring and it grows back and flowers beautifully," Mugridge says. "You don't have to prune them, but it keeps them contained if you have a small area you wish them to remain within. Otherwise you can let them grow, but they can get large."
There are times when a homeowner's best bet is to consult an arborist. Homeowners shouldn't try to prune a large tree themselves.
"I cringe when I see people on a ladder with a chain saw over their head, and their 2-year-old running around below them," says Mugridge.
There's a wealth of information, including step-by-step illustrations, on how and when to prune, and the best tools for particular pruning jobs.
The Web site www.treesaregood.com offers loads of material about pruning young trees, pruning mature trees, step-by-step illustrated pruning techniques, advice on when to seek professional help from an arborist, how to find an arborist near you, and more. The site is run by the International Society of Arboriculture.
An article about pruning apple and pear trees, on the Ohio State University Extension Web site, says, "A neglected but otherwise healthy tree will usually show a marked improvement in fruit quality as a result of pruning." To read the article, click here.
To find an arborist, go to asca-consultants.org.
There are many pruning tools to choose from. The Montana State University Extension Web site covers most of them, including illustrations of proper and improper pruning methods, at montana.edu/wwwpb/pubs/mt9304.html.
Books offer more information on pruning. One is "The Pruner's Bible: A Step-by-Step Guide to Pruning Every Plant in Your Garden" (Rodale, $21.95) by Steve Bradley, which also includes which tools should be used for specific jobs.
Another book is "Pruning Made Easy" (Cassell Paperbacks, $17.95) by M. Lombardi and C. Serra Zanetti, not to be confused with "Pruning Made Easy: A Gardener's Visual Guide to When and How to Prune Everything from Flowers to Trees" (Storey's Gardening, $19.95) by Lewis Hill.