The western red cedar Birdhouse treehouse at Longwood Gardens was built from logs found ins southeast Alaska. Just 255 square feet, it's the smallest of the three structures.
The Canopy Cathedral treehouse at Longwood Gardens was inspired by a Norwegian stave church.Its Douglas fir flooring was remilled from timbers in an old toothpaste factory in Canada.
Schoolchildren pose on the steps leading to the Birdhouse treehouse at Longwood Gardens shortly after the treehouse exhibition opened in April.
The Canopy Cathedral treehouse at Longwood Gardens has a 118-square-foot balcony.
The Douglas fir timbers that make up the columns, beams and rafters of the two-story Canopy Cathedral treehouse were milled from logs recovered from a 2002 wildfire in Oregon.
A large window on the second-floor of the Canopy Cathedral treehouse offers visitors a view of the Italian water garden.
The Adirondack-style Lookout Loft treehouse at Longwood Gardens has two viewing platforms connected by a walkway. Visitors reach it on a long winding ramp that is handicapped-accessible.
By Gretchen McKay Pittsburgh Post-Gazette
KENNETT SQUARE, Pa. -- Few things in life can make you feel like a child again. But clambering up open stairs to The Birdhouse, one of three custom-designed treehouses at Longwood Gardens, comes pretty darn close -- and not just because a crowd of giggling elementary schoolers is racing me to the top.
Twenty feet in the air and surrounded by leaves, this treehouse does offer a bird's-eye view of the Peirce-du Pont house and Peirce's Woods. But it's a far cry in both design and environmental friendliness from the makeshift shelter you might have enjoyed as a kid. No wonder the exhibit, which runs through November, is named "Nature's Castles: The Treehouse Reimagined."
Whereas most treehouses rely on the trees themselves for support, the Longwood structures use a new technology called a pin foundation system. The treehouse is anchored toa series of long pipes driven into the ground, leaving the trees limbs and roots unscathed.
All three have trees growing right up through their decks; the ADA-friendly Lookout Loft treehouse, which features two platforms connected by an ipe hardwood walkway, has two giant tulip trees spiraling through its roof. It was designed by Forever Young Treehouses, a Vermont nonprofit that builds only universally accessible treehouses. The other two are the work of Peter Nelson of TreeHouse Workshop in Seattle.
Treehouses might seem an odd addition to Longwood, one of America's greatest horticultural treasures. But trees are a long and important part of Longwood's history and mission; its founder, industrial wizard Pierre S. du Pont, purchased the original 202 acres to save a historic arboretum cultivated by the Peirce family in the late 1700s. Some of the trees they planted are still standing.
"We thought it would be a great way to tie the story of how Longwood began and the importance of preserving trees," says publicity coordinator Patricia Evans.
The idea for a display devoted to treehouses is not a new one nor one limited to the Northeast. The Atlanta Botanical Garden and Dallas Arboretum both recently featured treehouse exhibits. And Tyler Arboretum in nearby Media, Delaware County, in May opened its "Totally Terrific Treehouses" exhibition of 16 locally designed and built treehouses.
They range in size and scope from the simple "Kyle's Tree House" (a collection of hammocks suspended at different levels among the trees) to the elaborate "Thoreau's Cabin" (a life-sized replica of the writer's home at Walden Pond). The exhibition runs through the end of September. Plans are also under way for a tree exhibit at Morris Arboretum of the University of Pennsylvania to open next June.
A growing number of treehouses are also popping up in suburban back yards as more people discover -- or is it rediscover? -- how fun they are. Jonathan Fairoaks of Living Tree, a custom treehouse company in Glenmoore, Chester County, builds about one treehouse a month in such far-flung locales as Maine, Michigan and California.
Most, he says, are "family" treehouses that average 12 by 16 feet, are unfinished inside and cost between $8,000 and $20,000. But he's also built "live-in" treehouses three times that size that include electricity and running water. The only limitation is one's imagination.
People like treehouses, Mr. Fairoaks says, because they're easy to secure and go up quickly. Depending on size and degree of difficulty, most family treehouses can be completed in about a week. A respite from the busy world below, they're also relaxing.
"A treehouse allows us to be closer to the heavens," he says.
Longwood's treehouses, which took four months and $1 million to complete using largely salvaged materials, might not reach the stars. But they certainly amaze with their size, artistry and intricate details. Take the two-story. 589-square-foot Canopy Cathedral, the most ornate of the three structures. Inspired by a Norwegian stave church, it boasts intricate, diamond-shaped windows on the facade, a soaring cathedral ceiling and twin staircases leading a 118-square-foot balcony. There's also a large deck overlooking Longwood's fabulous Italian Water Garden.
The Birdhouse, which incorporates built-in benches under its windows and a sliding barn door made of Western red cedar, looks like a giant bluebird box. And Lookout Loft has 75 feet of ramps that lead to three viewing platforms and two separate structures, one of which is covered by a trellis instead of a roof. Its ornate hophornbeam handrail is modeled after the Gothic folly in Longwood's recently opened Indoor Children's Garden.
All three treehouse sites were chosen to take advantage of the natural beauty of the arboretum's woodlands, which means at least two -- The Birdhouse and Lookout Loft -- are in areas where visitors don't often go. But that only makes for a more interesting visit, says Ms. Evans.
The view from all three is probably better in the fall when the leaves have fluttered to the ground. But in summer, when the structures are awash in green, you feel very much like you're living among their branches.
"It's fantasy," says Ms. Evans.
"Nature's Castles: The Treehouse Reimagined" continues through Nov. 23 at Longwood Gardens, which is on Route 1 near Kennett Square, 30 miles west of Philadelphia. Admission is $16 for adults, $14 for seniors, $6 for students ages 5 to 22, and free for ages 4 and under; it's open daily from 9 a.m. to 6 p.m.. Information: 610-388-1000 or www.longwoodgardens.org.
"Totally Terrific Treehouses" runs through Sept. 28 at the Tyler Arboretum in Media, Pa. Admission is $7 for adults, $6 for seniors and $4 for children ages 3 to 15. Information: www.tylerarboretum.org or 610-566-9134.