It's tenacious, greedy, and fast. Sometimes it smells, and often it's messy. And chances are this rude invader--a runaway alien from Asia--is living, growing, and multiplying along the alley behind you house.
It's the Ailanthus altissima tree, though almost no one calls it that. Almost no one calls it the "tree of heaven" either, though this rather clumsy English translation of one of its East Indian monikers was once common usage. No, this invasive, weedy import is nowadays known as the weed tree, or the ghetto palm, or the stink tree. It's identifiable by its compound leaves (individual leaf stalks lined with rows of a dozen or more teardrop-shaped leaflets) and the pungent smell of its foliage and flowers. It boldly goes where no tree--and few other plants--will go.
The aggressive ailanthus sprouts from sidewalk cracks, the roofs of vacant buildings, and gaps in brick walls. It thrives along exhaust-choked median strips and in stony, sun-baked vacant lots. Young trees can grow six feet or more a season. Did I mention it's tenacious? Attack one with an axe and it will mock your efforts with scores of sprouts from the stump and roots. Its leaves and bark contain a natural toxin that restricts other plants from growing near it. And it's fiercely fecund: Individual trees produce more than 300,000 winged, wind-dispersed seeds a year. For better or worse, the ghetto palm has dug deep roots into Baltimore's urban ecosystem.
Though now largely reviled, the plucky tree was once purposefully planted and prized. The ailanthus fell from heaven to hell in a few short centuries.
The tree's home turf is northern China, and in ancient times it was referred to as "God's Tree" and used to shade Buddhist temples. It came to the West in 1751, when a Beijing-based priest sent ailanthus seeds to London. The hardy, fast-growing exotic created a stir in Europe, and it was soon planted along boulevards from Paris to Rome. The tree continued westward in 1784, when a Philadelphia plant enthusiast acquired some seeds. Its hardiness and rapid growth impressed American nurserymen too, and the Chinese tree was quickly and widely propagated. By mid-19th century, our smoke-choked, industrializing cities were putting a hurting on most trees--but not the intrepid, filth-immune ailanthus. It became the urban tree of choice, planted from Boston to Baltimore. Famed urban landscaper Frederick Law Olmstead incorporated ailanthus in some of his projects. Rich folks treated the Eastern immigrant as a manor-home ornamental.
So what went wrong? Well, it seems in the rush to embrace the rugged newcomer, a lot of its negative qualities were overlooked. Like its rapacious reproduction. Like its malodorous leaves and flowers (the bouquet of the latter I've heard equated with rancid peanut butter and semen). Like its weak branches, which are easily damaged by wind and snow. (A quick thunderstorm can leave the ground littered with its ailanthus twigs and leaves.) And while oaks can thrive for centuries, the ailanthus often begins to disintegrate after a few decades. Like certain Hollywood celebs, they live fast and die young.
By the turn of the 20th century, most city foresters realized that the stink tree was not a sylvan savior--but it was too late. The ailanthus was already running wild in urban America. No longer a denizen of curbside tree wells, the eager Asiatic took to growing where it could--which is just about anywhere. The ailanthus' image as a gritty ghetto survivor was solidified in 1943, when Betty Smith used it as an overarching metaphor in her earnest novel of tenement life, A Tree Grows in Brooklyn.
Today, the tree grows from Argentina to Canada. Ailanthus followed the highways out of towns to maraud rural woodlands, where its ravenous habits can have a detrimental effect on native flora and established ecosystems. (Many states have launched costly ailanthus-eradication programs.) But for all its foul habits, like all trees, it cleans the air by exchanging CO2 for oxygen. Many tree enthusiasts have mixed feelings about this Old World interloper--including Gary Letteron, a self-styled urban forester who has planted thousands of trees in Baltimore (currently bringing greenery to Pig Town as part of forestry program financed by the Open Society Institute).
"If I could snap my fingers and all the ailanthus would be gone, I'm not sure if I would," Letteron says. While he champions native species, Letteron concludes that in places where nothing else will grow, a weed tree might be better than no tree. "Birds aren't picky," he says. "They'll land on them."
Then again, we're coming on June, when ailanthus' stock is lowest. That's when its spindly branches erupt in bloom.
"I call it 'ghetto-palm mating season,'" Letteron says. "That's when whole neighborhoods will smell like cat piss."
Latest MP3s
