Arbor all-stars

When Jennifer and Rob Willey redid their landscaping a few years ago, Jennifer knew what she didn't want: the same old trees and shrubs that everyone else has.

"I like unusual plants. I don't like it when every yard looks the same," she said. So she took photos of trees that she admired, including evergreens at the Minnesota Landscape Arboretum.

Then she hired Cory Whitmer of Mustard Seed to design an evergreen bed for her Eden Prairie back yard featuring several distinctive "specimen trees" -- a weeping white pine, a weeping white spruce and a dwarf Korean lilac.

The whimsical weeping pine reminds her of an illustration from a favorite children's book, she said. "I like trees that look different."

These days, she's not alone. "People want something their neighbor doesn't have," Whitmer said. "In a lot of developments, the houses look the same. The only way to change the look from the curb is with color and landscape. And if you want a landscape that stands out, trees are the biggest statement."

Exotic 'gems'

Specimen trees are nothing new, of course. The Gilded Age estates of lumber and railroad barons often featured exotic ornamental trees, such as European weeping beech and ginkgo, set in the landscape like jewels in a crown.

"There's definitely a trend toward these variations," said Peggy Anne Montgomery, spokeswoman for Bailey Nurseries in Newport. Today's sprawling new homes take up so much land that smaller trees become a necessity, she said.

"All breeders are looking at more compact sizes and dainty varieties. They're grafting everything onto sticks these days, so they can fit into small spaces." Instead of the 12-foot lilac like Grandma had, today's homeowners are more likely to opt for a 4-foot Fairytale lilac, she said.

"People have a huge appetite for smaller plants," agreed Jeffrey Johnson, an arboretum horticulturist who specializes in trees and shrubs. "One large maple tree can take over your whole yard, and you end up doing shade gardening. With smaller plants, you can have greater variety."

What qualifies as a "specimen tree"? It's not so much the type of tree, but the way it's used in the landscape, said Josh Plunkett, an arborist with Top Notch Treecare in Minneapolis and author of "The Complete Idiot's Guide to Trees and Shrubs."

"A specimen tree is one tree of a different type that's a focal point," he said. Whether it stands alone or as the centerpiece of a garden bed, it has visual impact. "You see it and go, 'Wow!'" (The Arbor Day Foundation also takes a broad view, defining a specimen tree as one that has been "placed so people can gain the greatest enjoyment for the color, texture, scent or other pleasures it provides.")

But to warrant a starring role, a tree has to have star quality, according to Mark Stennes, a plant pathologist/arborist with S&S Tree Specialists in St. Paul.

"A specimen tree has to be good-looking," he said, citing good form, structure and vitality. "It's an aesthetic term. Green ash specimen tree is an oxymoron. That's not a particularly attractive tree."

A specimen tree should have multiseason interest, such as an unusual shape, flowers, fruit or fall color, said Johnson of the arboretum. "It connotes standout, something you notice," he said, "not just a big green blob with brown bark in the wintertime."

And when a comely tree catches your eye, make sure you do your homework before you open your wallet.

"People tend to see something fancy and want it in their yard," said Plunkett. Those beautiful river birches you admired along the St. Croix, for example, may struggle in your heavy clay soil. "You can't just buy a tree; you need to choose the right tree for your type of soil."