Treacherous Trees

Poet Joyce Kilmer wrote: "I think that I shall never see a poemas lovely as a tree." Throughout history, trees have inspired poets and held a place in the hearts of nature lovers young and old. Practically speaking, a well-established shade tree can cut utility bills and improve the quality of outdoor air. Along rivers and creeks, the tree's roots help prevent erosion.

But when a tree begins to die, it can pose a danger to homes, cars and people. Large roots may buckle curbs and sidewalks, becoming a hazard to pedestrians and interfering with street drainage.

In many cities, with the exception of some commercial developments or in instances in which trees are maintained by a homeowners' association, trees growing in the parking strip - the stretch of ground between the sidewalk and the curb - belong not to the homeowner, but to the city. And while trees 50 inches around or larger may, by city ordinance, be designated as "heritage" trees - a city is within its rights to remove dead and dying trees or those it judges to be a danger to health, life or property.

Should a city fail to remove a diseased city-dedicated tree that subsequently topples, or one that drops a destructive branch on someone's house, car or head - the city, as owner of the tree, might be found liable. Homeowners who fail to properly care for and monitor large trees in their yards are similarly at risk in the event a tree or branch falls on a visitor or neighbor.

Finding the right trees for an urban setting

Trees are important to the aesthetics of a city. Retaining diversity in city trees is important, tree experts say, because maintaining a variety means more resistance to tree pests and blight that can wipe out an entire species. Arborists say, for example, that while the 30-feet-tall-when-mature Chinese pistache isn't likely to provide much shade for homes that sit back any distance from the street, it does have the advantage of growing shorter than power lines. Taller trees are at risk of being "topped" by utility companies, a practice, foresters say weakens a tree and makes it vulnerable to disease and pests. A tree so-disfigured is also unsightly.

A favorite urban tree is the Autumn Purple American Ash. It's resistant to pollution and pests, grows to a nice, shady 50-60 feet and displays beautiful fall colors of purple and deep crimson.

Bigger city-owned replacement trees are possible if parking strips are 10 feet wide, or curved out around the tree roots as is done in Los Angeles.

Is your tree healthy?

Homeowners concerned about the health of their own trees can be alert for signs that one is in decline. Landscape experts say look for dead branches in the crown, less leafing out, hollow or decaying trunks and branches (as evidenced by visible holes), even a trunk that 'Y's - because moisture can collect in the 'v' and begin the decaying process. On the other hand, if you want to attract birds and wildlife that nest in holes in trees, consider that, too, when you're thinking about removal.

What Tree Is That?

To recognize the more common trees found in the Western United States, send a $3 check with "What Tree is That?" on the memo line to:

The National Arbor Day Foundation

100 Arbor Avenue

Nebraska City, NE 68410

For more on planting the right tree in the right place, visit http://www.arborday.org/trees/righttreeandplace/righttree.cfm.