Plant sleuth: Tracking a tree to China

Flowers of the paulownia tree. — Carlos Calamar/Flickr

I’m no Sherlock Homes, but every now and then I’m asked to play detective when someone shows up at my door with another horticultural mystery. On one occasion it was my neighbor, who arrived with a large brown paper bag and a stump-the-stars attitude about his latest find.

First, he pulled out a deep green, heart-shaped leaf with a texture like the finest velvet; fully a foot wide and high, it was big enough to wear as a sun hat. Next came a branch of twiggy growth bearing a dozen or more seedpods the size of pecans. I could honestly say I’d never seen anything quite like it before.

The plant in question, a tree of some 20 feet, was growing beside a building in the parking lot of his workplace, not far from the industrial waterways of New York Harbor. The location of the find fueled speculation that this exotic specimen might be an escapee from some cargo ship, a rare tree not seen outside the Malaysian jungles of Kuala Lumpur, for instance.

Before you could say “Elementary, my dear Watson,” I was knee-deep in field guides and tree encyclopedias. Since this was clearly no common Northeastern species, my initial thoughts centered on the catalpa, which I knew to have large, heart-shaped leaves. Although I have no close acquaintance with this tree, more common in southern states, I have sometimes seen them grown in Victorian-era gardens.

But no. According to the books, catalpa produces seedpods that look like string beans, so it was torpedoed. Out of some dusty corner of my brain came another guess, based vaguely on a stand of trees seen long ago at Longwood Gardens in Pennsylvania, and a spring to the Van Vleck Estate and Gardens in Montclair.

“I’ll bet it’s a paulownia,” I said — and in retrospect, it’s too bad no one threw money on the table.

Paulownia was exactly right, and some of my hunches played out perfectly. This tree was named for Anna Paulownia, a Russia czarina who married a Dutch prince back in the 18th century. It is also known as the princess or empress tree. But the tree’s horticultural baptism came late in the game.

Paulownia tomentosa, leaves and seed pods. — Jon Sullivan/Flickr

The species is native to China, where it has been cultivated for at least 2,000 years. Paulownia reached the United States in the mid-1800s, establishing itself first along the eastern seaboard. Why there? Because its empty seedpods were used to protect breakables shipped here from China, that’s why. I was right about the method of its arrival, just off on the timing by roughly 200 years.

Our crash course on the paulownia yielded more goodies. The strong, light lumber is used by the Chinese for moldings, cabinets, veneers, furniture, musical instruments and coffins. Japan prizes it highly. Doting Japanese fathers traditionally planted a paulownia when a daughter was born, felled it when she was betrothed and used the timber to construct a wedding chest.

Former president Jimmy Carter had about 45 acres in paulownia at his Georgia estate, and in 1999 built a glass-fronted bookcase of paulownia. Don’t giggle — he sold it at a charity auction for $230,000.

But wait — there’s more. Paulownia leaves, high in nitrogen, are good fodder for livestock. Humans find the leaves make a nice tea, and the lovely, fragrant flowers not only make quite a show in spring, but are said to be tasty in salads. Since the blossoms contain prodigious amounts of nectar, attracting bees, the paulownia is also a terrific honey source.

The most amazing thing about the paulownia is probably its rate of growth. In the first year, it can shoot up 10 to 15 feet. By the second season, it’s blooming, and by the third, it’s a respectable shade tree at 25 feet. Planting instructions from one supplier actually read “Put it in the ground and stand back three paces.”

This might recommend the paulownia for new landscapes, an “instant” shade tree for the new McMansion. But you should know that those big leaves (up to 36” long) can be a nuisance to rake up, and that a large tree can produce 20 million seeds a year, potentially creating a paulownia plantation whether you want one or not. I’d guess the tree would be ideal for temporary effects while permanent trees achieve some size, and could then be cut down for your daughter’s wedding chest.

Of nine recognized varieties, the naturalized Paulownia tomentosa is the most cold-hardy; ‘Sapphire Dragon,’ with true blue flowers, is the showiest; and Paulownia elongata ‘Carolinia,’ bred by the timber company Carolina Pacific, is the only hybrid created expressly for American growers. If you’re interested, check for sources with the American Paulownia Association.

Meanwhile, my neighbor’s co-workers have spruced up their paulownia’s site and four of them are trying to propagate seeds (Collect them in September when they’re ripe, guys, and don’t cover the seed — they need light to germinate.) My neighbor is threatening to run away to Australia to start a paulownia plantation. And my reputation as a plant sleuth is, for now, secure.