A few miles off Route 50, Paul Kovenack has created an oasis in his modest Arlington back yard. Gone are the neatly mowed lawn, pots filled with flowers and clumps of English ivy scattered around the yard.

Instead, about 135 kinds of plant life make their home on Kovenack's property, including pungent sassafras, towering bamboo and about a dozen kinds of leafy fern.

In addition to giving Kovenack a wonderfully lush view from his bedroom window, his property has recently been certified as a Backyard Wildlife Habitat by the National Wildlife Federation. This means his yard helps protect and nurture wildlife by providing the survival essentials of food, water, shelter and places to raise young.

"I retired from the State Department and wanted to get as close to nature as I could in my retired years," said Kovenack, sitting on his deck on a recent sun-dappled afternoon. Besides, he added, "I'm too lazy to mow grass."

An avid outdoorsman, Kovenack, 63, considered moving west and planting himself in the Grand Tetons or near Yellowstone Park. But he also loves to dance, and opportunities would be scarce in those areas. Kovenack decided that if he couldn't go to the wilderness, he would bring the wilderness to him--at least a small slice. So after 25 years at the Watergate in Washington, he moved to Arlington about two years ago and got started uprooting and planting anew.

There are 965 Backyard Wildlife Habitats in Virginia, with 38 in Arlington County, 36 in Alexandria and 261 in Fairfax County. According to Mary Burnette of the National Wildlife Federation, there was a 22 percent increase nationwide in certified habitats last year. Growth of habitats in Arlington is slightly below average, with four yards being signed up so far this year and six last year.

Kovenack's plan for the yard involved banishing the abundance of English ivy, which prevents other plants from growing, and replacing it with a variety of nut- and fruit-bearing vegetation that is native to the area. According to the wildlife federation, native plants may support 10 to 50 times as many species of native wildlife as nonnative plants. "The object here is to provide enough natural food with native plants so that I could go away and the birds would have enough to eat," Kovenack said.

For planting guidance, he turned to the Virginia Native Plant Society. Through that group, he learned about the Backyard Wildlife Habitat program and folded its requirements into his landscaping plan. For example, as he reworked his back yard with the help of Arlington landscape designer Rick Blaine, Kovenack left standing a 40-foot-tall tree stump.

"It provides nesting sites and crevices for woodpeckers and other birds," he explained. He also put in a water pump (attractively encased in bamboo) that feeds a beautiful stone pool, the perfect spot for thirsty animals or birds in need of a wash. The pool recycles its water. For the colder months, he installed a heated birdbath on one of his deck railings.

"I enjoy working outdoors and trying to heal the land, which has lost its value as habitat," Kovenack said.

Although he has lived in his house for only three "growing seasons," the healthy, tall flowers and plants seem to have thrived there for years. And it appears impossible that any more vegetation could fit, especially because the newly planted dogwood and other saplings will only grow bigger.

But for Kovenack, the yard will continue to evolve. "This is always a work in progress," he said. "This is just the beginning of a long-term project."

Inside his house, which Kovenack renovated extensively to resemble an airy ski lodge, hangs a large picture of 20 or so brown bears fishing in an Alaskan stream. Most of Kovenack's wildlife visitors have been birds, although he once saw a deer, which he said was thrilling. He has counted 30 bird species hovering around his two feeders or alighting on the nearby sunflowers or hollyhocks. Once he spotted 13 cardinals hiding in his bamboo grove.

After hours spent watching and identifying his airborne guests, Kovenack developed an attachment to a one-legged, black-capped chickadee he named Ada, after the Americans With Disabilities Act.

"It's been marvelous to see how she has coped with her major disability," Kovenack said as he pointed out Ada's agility at feeding upside down.

When Kovenack lived at the Watergate, there were rules against visible flowers and bird feeders on balconies, he said. "I secretly fed a mockingbird with peanut butter for two years," he said, adding that the bird preferred creamy to crunchy.

Although he has mainly witnessed endearing family scenes, such as a doting mother feeding her young, the yard also has been the site of animal kingdom blood and gore. "Once a Cooper's hawk seized a chickadee," said Kovenack, shaking his head. "It was pretty violent."

To get his yard certified by the National Wildlife Federation as a Backyard Wildlife Habitat, Kovenack filled out an application in which he detailed what his yard provided in terms of food, water, shelter and nest and den areas. He also included an array of photos, a rough sketch of the yard and a $15 program enrollment fee. Any size yard is eligible to be certified, and the federation says even a window box with flowers helps feed birds and butterflies.

In less than a month, Kovenack received his certificate (which he framed in green wood) and a sign, which he has placed in the yard. So far the sign hasn't encouraged any of his neighbors to take the plunge, though Kovenack said at least one person on his quiet cul-de-sac seems interested.

In his home, he keeps a bulletin board of photos of his house and land, before and after it became a haven for wildlife. "Thomas Jefferson once said, 'Though an old man, I am but a young gardener,' " Kovenack said. "I feel the same way. It's a wonderful way to learn new things."

For information, call the National Wildlife Federation, 703-790-4000, or visit the Web site, www.nwf.org/habitats.

CAPTION: State Department retiree Paul Kovenack says he "wanted to get as close to nature as I could in my retired years."