A few blocks from the Capitol sits a miniature version that, from a distance, appears plastic. But a closer look reveals that this replica is entirely organic. Its Dome is made of sycamore leaves, winged euonymus, wheat and other natural products. And with detail work including screw pods and acorn caps, it certainly looks like the real deal.

The replica is part of the Botanic Garden’s fourth annual holiday display, “A Midnight Clear.” In addition to the miniature Capitol, the exhibit, created by landscape architect

Paul Busse with the support of his Kentucky company Applied Imagination, features replicas of the Jefferson Memorial, the Washington Monument, Ford’s Theater and the Library of Congress. Outside, 10 trains snake their way around the tracks of a garden railway, with the real Capitol Dome as a backdrop.

Busse said he thinks the Capitol replica’s striking appearance draws visitors in from a distance. Many are surprised when they get closer and realize the re-creation is entirely organic, he said.

“What intrigues me the most is that the thing could have been made from plastic,” he said. “I think ‘wow’ is one of the more common words used there.”

The Capitol replica took 600 hours to build. Twelve Georgetown town house replicas — made of walnut shells, lotus pods and branches from a hazelnut tree — took about 24 hours each, Busse said.

“It might be a while before we top the Capitol,” he said. “It just has such a wonderful presence there.”

The exhibit also was built with a mind toward the environment. All of the replicas are lit using energy-efficient LED light bulbs, Busse said.

“A Midnight Clear” attracts a very large crowd, said Holly Shimizu, executive director of the Botanic Garden. Last year’s theme was “Savor the Season” and featured an Italian-influenced style known as Della Robbia and a brilliant crimson-purple and lime-green color scheme (this year’s colors are blue and silver).

Shimizu estimated that 3,000 to 4,000 visitors circulated through the garden each day of the 2006 holiday display.

“It gets really packed when the kids are not in school,” she said, because it’s a fun activity that has educational value.

Capitol Hill residents also flock to the exhibit, Shimizu said. They especially appreciate the extended evening hours.

“They feel like it’s theirs, and that’s how we want them to feel,” Shimizu said.

When the USBG began its holiday display of organic D.C. buildings and miniature trains four years ago, the exhibit was entirely indoors, Shimizu said. The train replicas moved outside two years ago because of the heavy traffic the exhibit generated.

“To avoid the crowd problems, outside was a very good solution,” Shimizu said.

The outdoor garden railway has more than 800 feet of track, which winds through tunnels and over a 45-foot suspension bridge. More than 20 kinds of plant materials, including pine cone scales and tree bark, are incorporated. The exhibit is surrounded by conifers draped in blue lights.

The 10 miniature trains are all historic replicas, Busse said. Some are based on trains that ran on the Pennsylvania, Baltimore and Ohio lines.

“There’s a lot more than meets the eye,” Shimizu said.

“A Midnight Clear” admission is free. The exhibit is open to the public from 10 a.m. to 5 p.m. every day including weekends and holidays through Jan. 6, and until 8 p.m. on select Tuesdays and Thursdays. For more information, call 202-225-8333 or visit usbg.gov.