If there's one thing that makes Lexington's urban foresters flinch, it's a line of pear trees — also known as wind bait, invasive species or the landscaping plague of the '90s — lined up along the city's streets.
Although the pear trees are lovely this time of year, with white blooms that fall like gentle snowflakes, they have weak wood and are susceptible to any big blast of wind, which can fracture them like toothpicks.
Because Lexington doesn't have an adequate tree canopy — the cover of tree leaves, branches and trunks that cover the ground when viewed from above — homeowners are urged to plant trees in their yards and near the street.
But some residents swear off trees after having difficulty with those previously planted on their property. That includes not only the spindly pear trees, but silver maples, popular for landscaping with houses that were built in the '50s and '60s. They have vast root systems that often break the ground above and the pipes below.
City foresters urge homeowners to find the right trees for the area, many of which are native species, and not to simply go for an affordable tree or a weak tree that creates a brief, flowery spectacle in spring.
The right tree, city forester Tim Queary said, "is going to be a little bit more expensive, but you get what you pay for."
"We have to promote street trees," Lexington city government arborist John Saylor said. "We don't want one species to dominate the canopy. We preach diversity."
The perils of having one species dominate the neighborhood tree canopy is seen in Lexington's Ashland Park neighborhood, which was known for its towering pin oaks. Those trees, some of which reached 80 feet, have been lost in great numbers since the late 1990s.
Wanda Jaquith, a former president of the Ashland Park neighborhood association, said the roots of the trees were cramped. Some of the trees that were taken out had barely any root ball left, she said.
Now, said neighborhood tree enthusiast Bill Loggins, the street trees — generally those planted between the sidewalk and the curb — include a mix of flowering and shady trees, including maples, serviceberries, yellowwood, tulip poplar and swamp oak. The trees won't have the towering presence of the pin oaks, he said, because of the utility lines above them. Loggins concentrates his efforts on caring for trees in the Ashland Park neighborhood's medians.
Given the unsuitability of some species as street trees, why do homeowners continue to plant them? Several reasons, Queary said. The trees continue to be heavily promoted: Who hasn't seen an advertisement for fast-growing trees that allegedly create an almost immediate wind screen?
The non-favored species also are heavily stocked by the big-box home-improvement stores, Queary said, and "the trees are cheap."
But cheap trees might cost you far more in the long run. If you own a house in Fayette County, you might not know that are you responsible not only for the sidewalks but for the strip of grass between the sidewalk and the street.
Here are the basics on what you should know about your street tree:
■ The developer of the neighborhood probably planted the first street trees in front of your house when the houses were built.
■ Street trees must have a minimum of 12 feet clearance from the street surface, and seven feet from the sidewalk surface. That allows pedestrians to use the sidewalks and trucks (such as mail and delivery trucks) and emergency vehicles to travel the street without impediment.
■ Not abiding by the street tree regulations could result in a fine.
■ You need a permit before removing or planting a street tree. The permits are free and available online at Lexingtonky.gov/forestry, or you can call the Urban Forestry Program at (859) 425-2859.
■ Some financial assistance might be available for street tree removal, stump grinding and tree planting. Call (859) 425-2859 for more information.
Lexington urban forestry: Livegreenlexington.com
Approved street trees in Lexington
Large trees (more than 50 feet tall): American elm (only Dutch elm disease-resistant varieties such as Princeton, Valley Forge and Liberty), chinkapin oak, ginkgo (fruitless cultivars only), Japanese zelkova, lacebark elm, London planetree, northern red oak, scarlet oak, shingle oak, Shumard oak, swamp white oak, sweetgum, sugar maple, sugarberry, water oak, willow oak and white oak.
Medium trees (25-50 feet tall): Black gum, Carolina silverbell, goldenraintree, hardy rubber tree, hedge maple, hophornbeam, Japanese pagoda tree, Japanese tree lilac, katsuatree, Kentucky coffeetree (fruitless cultivars only), littleleaf linden, Persian parrotia, red maple, sassafras, thornless honeylocust, Turkish filbert and yellowwood.
Small trees (10-15 feet tall): Allegheny serviceberry, American hornbeam, amur maple, crabapple varieties, eastern redbud, fringetree, flowering dogwood, hawthorn varieties, kousa dogwood and tatarian maple.
Prohibited street trees: All flowering pear, birch varieties, catalpa varieties, common apple, female ginkgo, mulberry varieties, pin oak, Siberian elm, silver maple and evergreens.
Cheryl Truman: (859) 231-3202. Twitter: @CherylTruman.