Unlike the lush foliage lining West Coast interstates, landscaped freeways in Utah are rare.

The state's desert climate has been a convenient excuse for leaving the medians and side slopes barren.But environmental studies addressing the impact highways have on soil and plant life have taken root in the minds of state transportation officials. And in the past five years, landscaping has suddenly been elevated from an ignored luxury to a legal requirement.

Today, any rebuilding or new construction of existing highways must mitigate the impact on soil erosion, vegetation and water. Take I-215. Dry dirt and weeds border many of the older sections. But along the more recently completed east leg, crews are installing watering systems and nursing struggling roadside seedlings.

Turning attention to gardening hasn't been an easy adjustment for the Utah Department of Transportation, which prides itself in building roads, not tending flowers.

"We are on a learning curve," says Conley Thompson, UDOT's landscape architect. "I am in here with a bunch of engineers and they are trying to be progressive and show good faith" in meeting new environmental impact requirements.

Landscaping a highway is more complicated than laying sod and planting petunias. Those choices may work fine in a small private yard, but UDOT must consider water conservation and low maintenance when selecting flowers, trees and shrubs.

That means finding plants native to Utah's desert climate.

"Some people get upset when you mention native plants because all they think of is acres of sagebrush," Thompson said. "That is a native plant, but Utah has the widest range of native plants out of all the contiguous states. It may be the third driest state, but it is very diverse geographically from St. George to Logan. You can picture the various plants ranging from desert to alpine."

Firecracker penstemons, blue flax, iris, rabbitbrush, wild roses, silver buffaloberry, various pine trees and cottonwoods are a few of the flowers, shrubs and trees taking root along the east leg of I-215.

Motorists won't notice the young landscape until it becomes permanently established in about three years. Instead, Thompson regrets, the only landscaping most people see is the green grass at the 1300 East interchange of I-80.

The rivers of water running on to the road attest to the costly maintenance and lack of conservation of that project.

UDOT takes comfort in knowing the grass was requested by Sugar House Park, which also pays for its maintenance.

Thompson said there are alternatives to rainbirds shooting water through the air to keep plants alive. He envisions a landscape that can survive on natural moisture. But it has taken time, money and a lot of work to make it happen.

Drought conditions for the past three years haven't helped. UDOT has employed various methods, however, to help the young native plants get a head start.

Water-conserving drip-irrigation systems have been installed to soak the new seedlings using a minimal amount of water. Catch basins have also been constructed in planting areas around interchanges to take advantage of rain water.

Also, the new plants have been planted in tubes that train the roots to reach deep into the ground for water, which will augment surface watering. And to prevent rainfall from eroding the plant dimpled-hillsides bordering the freeway, UDOT has spread blankets of shredded aspen bark that also hold in moisture for young seedlings.

Landscaping doesn't come cheap. The I-215 project will cost $2.7 million, and the painstaking effort of restoring wildflowers along U.S. 189 in Provo Canyon is estimated to cost about 1 percent of the project's $90 million price tag.

Thompson said there are more to the benefits of freeway landscaping than meets the eye.

He hopes people will take notice of and implement water-conserving gardening methods in their own yards, saving a commodity that will become more scarce as population grows along the Wasatch Front.

Thompson also ties freeway landscaping to economic development. First, there are the cottage industries that provide seeds of native plants for UDOT. He noted a host of seed gatherers springing up in Utah County competing to become the state's supplier for wildflowers in Provo Canyon.

Then there is the "image" the state wants to project to visitors. Thompson mentioned the unsightly drive from the airport to Salt Lake City.

"That's a major entrance into the city for those who fly into Salt Lake City," he said. "We need to do something if we are going to invite the world to Salt Lake City."