Constable: Favorite tree on Arbor Day? Morton leader has many

We barely step onto the sidewalk outside the Morton Arboretum's administration office in Lisle when Todd Jacobson stops and points.

"This is one of my favorite trees," says Jacobson, the arboretum's head of horticulture. Towering above us and just starting to fill with green glossy leaves, the Accolade elm carries special meaning for Morton Arboretum. The species was created by George Ware, the former head of research at the arboretum.

"This is the first of many elms we've hybridized in the hope replacing American elms lost to Dutch elm disease," Jacobson says.

An Asian hybrid,

the Accolade elm can grow 50 to 60 feet high, sports leaves that turn a majestic yellow in the fall, and resists Dutch elm disease, elm leaf beetles and other potential ailments. This particular tree is about 40 years old and was moved about 30 feet from its original location one winter 30 years ago.

"That shows you it's a tough tree," Jacobson says, noting the tree can survive droughts and put up with automobile pollution. "We like this tree because it's a tough, urban elm."

But Jacobson also includes a nearby Kentucky coffeetree in his list of favorites.

"The seed pods rattle so kids like to play with them," he says.

This particular tree was one of the first planted when Joy Morton opened the arboretum in 1922. Morton's father, Julius Sterling Morton, was the secretary of agriculture under President Grover Cleveland and came up with the idea of Arbor Day, which we celebrate on Friday.

The elder Morton moved to Nebraska in 1854 and immediately determined that the state could use some trees. As editor of the Nebraska City News, he encouraged people to plant trees. In 1872, he persuaded the state to declare the first Arbor Day, during which Nebraskans planted an estimated 1 million trees.

Another "tough, urban tree," the Kentucky coffeetree grows slowly but puts forth a "brilliant gold" display every fall, Jacobson says.

"This is what we do. We test trees," says Jacobson. "We'll kind of push the envelope sometimes."

One species of evergreen tree was getting rave reviews, "and then one harsh winter killed it," Jacobson says.

"But this is one of my favorites," he says, reaching out to grab the limb of a small American hornbeam as if he's shaking hands. "You get fantastic fall color, with yellow, orange and red."

It's sometimes called a blue beech because of its smooth, blue-gray bark. Its neighbor, a Katsura tree, also offers an attractive bark. Native to Japan, the katsura's heart-shaped leaves emerge reddish-purple, turn a blue-green in the summer and are yellow by fall. Its ability to handle a cold winter, a dry summer or the pollution and abuse often doled out to suburban trees puts the katsura on Jacobson's list.

"This is what constitutes my favorites - trees that are tough," he says.

He praises the Cornelian-cherry dogwood with its tight clusters of flowers, the European beech with its copper-colored leaves, the short Magnolia "Ann" with its reddish-purple flowers, the mighty sycamore with its white bark, the male "Princeton Sentry" ginkgo that doesn't stink, the hardy bald-cypress that drops its needles, the stunning collection of flowering crabapple trees, and the omnipresent redbuds.

"I have lots of favorites," Jacobson says. "Diversity is key."

They all have different looks and features, but trees all help clean pollutants from our air, absorb carbon, create oxygen, reduce flooding, reduce energy costs by shading homes from the elements, improve property values and have even been credited with improving health and reducing crime.

One 2013 study says the 157 million trees in Chicago and the suburbs provide an economic benefit of $51.2 billion a year. Show up Friday at the arboretum dressed like a tree, and you get in free.

There's also the emotional attachment to trees that are fun to climb, great for picnics, provide the perfect shade or serve as homes to birds and other wildlife, Jacobson says.

"In my yard, I'm hearing the robins sing every morning," says Jacobson, who lives in Wheaton. Unlike many suburban cubicle-dwellers, he also can escape the stress of his office quickly.

"It's not a bad place to work," Jacobson says, smiling as he passes yet another tree on his long, long list of favorites. "If I have a bad day, I just take a walk."