Trees, like good friends, require tender loving care

By Dan MacArthur
North Forty News

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Healthy trees are happy trees that add beauty, comfort and value to any property.

And the best way to ensure that trees stay healthy is through regular care and maintenance that keeps them strong enough to withstand ills that can be costly, time-consuming and much more difficult to fix later.

"Trees are designed to take care of themselves. A healthy tree is not going to take a lot of supplementary care," said James Knotts. Owner of Tree Top Tree Service, he is a certified arborist who helps property owners develop long-term tree-care programs.

One of the most important factors in arboreal physical fitness is proper pruning to remove dead or damaged branches that can contribute to disease. Pruning also offers the opportunity to shape trees, promote orderly growth and permit adequate flow of air and sunlight through the branches.

"Trees need pruning in order to function properly," said Knotts.

Fort Collins city forester Tim Buchanan said this is the time to identify and remove dead branches. If no buds are apparent early this month, he said it's a safe assumption that the wood is dead and should be pruned.

The National Arbor Day Association recommends whenever possible encouraging side branches that form angles a third off the vertical central trunk at the 10 or 2 o'clock position. Most species of trees should have a single trunk with side branches at least a third smaller than its diameter.

If it is necessary to remove a main branch, the association recommends cutting it back to where it is attached to another large branch or the trunk. Do not truncate or leave a stub. Illustrated information on the proper pruning method is available on the association's web site www.arborday.org.

Now is also the time to trim suckers from tree bases and stems, Buchanan said, in addition to removing low-hanging branches from the trunk. Such trimming should not exceed a third of the tree's total height.

Ideally, Knotts said, pruning should be done in the fall and winter but can be done now. If so, the National Arbor Day Association recommends no more than a quarter of a tree's foliage be removed in season.

Buchanan said a single dead branch on a pear, crabapple, mountain ash and hawthorn tree could be a sign of highly contagious and destructive fire blight. Infected branches must be carefully pruned below the evidence of blight, he said, with the branches disposed of properly and shears disinfected after each cut to avoid spreading the disease.

For larger trees, Buchanan suggests seeking pruning advice from a professional arborist. In selecting one, he said, property owners should be sure he or she is certified by the International Society for Arboriculture, the largest and most-recognized organization of its kind. "That's a very good credential," he said.

Buchanan said potential customers also should consider how long the company has been in business, ask for and research references, and look for well-maintained vehicles bearing the company's name on the side. In Fort Collins, they also should be one of the 25 licensed by the city, he said.

And never, ever under any circumstances pay for work in advance, Buchanan stressed.

Along with proper pruning, Knotts said, adequate watering is essential. He recommends deep-watering trees at least once a week during the growing season and monthly during the winter. To determine the need, Knotts said, take a handful of soil from beneath the tree. If it crumbles, it's too dry. If it wrings water, it's too wet. If it holds together, it's just right.

A good way of watering, he said, is to place a hose at a slow trickle at the base of a tree and allow it to thoroughly infiltrate the soil in the surrounding drip line extending to the outer the edge of the canopy. Leave the hose there for two to three hours, he said, or until the water begins to run off.

Knotts said mulching beneath trees greatly helps retain moisture, except for stone that can actually cause damage because of the heat it retains and reflects. However, he said, the mulch should be pulled away from the trunk to prevent the potential for disease.

Off-color trees may need a feeding of iron or nitrogen in mid to late June, according to Buchanan. He suggested that a professional make that assessment.

Buchanan said spraying is a last resort, usually not necessary for healthier trees better capable of withstanding assaults by pests. "I don't recommend spraying unless you're sure you've got something," he said.

The problem with pesticides, Knotts said, is unless they're appropriate and properly applied, they also kill beneficial insects along with the undesirable.

Locally, Buchanan said, there are few serious concerns other than a pine nematode possibly infecting Scotch pines, making them brown or yellow and weak. "If people have a sick Scotch pine, we'd like to know," he said.

Buchanan said there are fears that a potentially destructive emerald ash borer could get established here. It's now limited to the east and Midwest, but he cautioned against importing any firewood that could introduce it to this region.

Some of the best sources of information about trees and their care, according to Buchanan, are the fact sheets available from Colorado State Cooperative Extension at www.ext.colostate.edu. "That's a real good resource a lot of people don't know about," he said.