Every year, thousands of winged visitors flock to Linda McBride's garden. It contains a smorgasbord of butterfly treats, including butterfly bush, lantana, impatiens and verbena.

With plentiful food and superb hospitality, many butterflies don't need to venture far. And so, McBride's screened porch has become a maternity ward.

McBride serves as a midwife of sorts to area butterflies, hand-raising generations of her "babies" before releasing them.

Swallowtail and spicebush butterflies and cecropia moths all call her Henrico County garden home. But McBride, a member of Henrico's School Board, is spending extra time this year working with a program to preserve one of the area's most well-known species, the monarch butterfly.

"Butterflies are a natural treasure. Their very existence is being threatened by habitat destruction. What I do is help to increase their chances for success," McBride said. "For me, it is truly a labor of love."

From her kitchen window, McBride watches as butterflies lay eggs on the plethora of nectar plants on her deck and in her garden.

"As soon as the babies come out, I bring them inside to protect them because there are a million different predators that will eat either the eggs or the babies. Spiders will drag them off, parasitic wasps will sting them. They're vulnerable to all kinds of diseases. Birds will eat them."

When McBride finds a caterpillar, she'll carry it in to the screened porch, sometimes while it's still munching on leaves. There it joins others that live on potted plants or branches.

When it nears chrysalis time for the caterpillars, she moves them to sturdy plastic boxes where they can attach to the lids. McBride checks these boxes throughout the day -- more frequently on warm days -- so she is ready to release the hatchlings.

Butterflies are aesthetically appealing, but also important for several reasons, said Tom Brinda, assistant executive director of horticulture and education at Lewis Ginter Botanical Garden. "Those butterflies are pollinators. Part of life relies on the insect world to pollinate flowering plants," he said. "They continue to remind people what a delicate balance of life this is."

In the safety of McBride's screened porch and under the watchful eyes of her three cats, the caterpillars graze and grow. She brings in potted plants and cuttings for them. Monarchs eat only plants in the milkweed family, while black swallowtails are attracted to members of the carrot family -- fennel, dill and parsley.

After several weeks, they'll begin to go into the chrysalis stage, where they'll stay suspended before emerging as butterflies.

Any given year, she'll have hundreds of monarchs and black swallowtails, plus a few others, including sleepy oranges, cabbage whites and spicebush swallowtails.

During most of the season, she releases them into the wild.

But for monarch butterflies that hatch in late August or September, there is another step: Before releasing them, McBride uses tweezers to gently attach tiny tags to their wings.

The tagging is part of the Monarch Watch program at the University of Kansas. The program monitors the monarch migration and educates the public and lawmakers about environmental factors that affect the butterfly population.

"These particular babies are known as the migratory generation," she said. "Their job is to migrate to Mexico and semi-hibernate through the winter. In the spring, they develop, begin mating. Those babies grow up and fly farther north until several generations later they're in southern Canada again."

But the monarchs' existence is threatened.

"If they can't make the migration, if they die on the way because there is no milkweed or nectar source, if they die because logging is taking all the trees away from them, we will not have monarch butterflies any more.

"That's why there is a big conservation program going on."

Volunteers have planted host and nectar plants along the routes between Canada and Mexico. As the butterflies migrate, enthusiasts across the United States and Mexico look for the tags -- mainly on dead butterflies -- and report findings. Tag numbers are posted online at the Monarch Watch Web site.

"I can check the Web site and see if one of my babies made it down there," she said.

This week is prime season in Virginia for butterfly migration, McBride said. "In the mountains, you can see hordes of them flying together."
Contact Lisa Crutchfield at (804) 649-6362 or lcrutchfield@timesdispatch.com.