WESTPORT -- Talk to a person with a neighbor growing a stand of bamboo on the property line, and you're going to hear some words that can't be printed in a newspaper.
"It's a nightmare," said Priscilla S. Weadon, of Westport, whose neighbor on her street planted bamboo a few years back. Now it's invading her property, and she's at her wit's end.
"Once you're aware of it, you'll see it everywhere," she said. "They're popping up all over the place in my yard. You can't kill it. I've used some really powerful chemicals. Didn't work."
Westport, like dozens of towns and cities in Connecticut, is home to several astonishing mini-forests of yellow groove bamboo. If your only experiences with the plant are the torches at your neighbor's tiki party, you're in for a jaw-dropping experience.
In a mature stand, the stems, or culms, are between two and three inches in diameter. Their density is sufficient to keep a second-grader from squeezing through. The layer of delicate leaves begins at about the 6-foot level and continues up to a height of 35 feet or more.
The plant produces an infrequent crop of seeds, so its primary strategy of spreading is though its rhizomes, the underground stems that are the source of the plant's nightmarish reputation.
Rhizomes fan out inexorably to claim new turf. In essence, a stand of bamboo is a single plant because all of the rhizomes are interconnected. Barriers such as sidewalks, fences and stone walls offer little resistance.
Caryn Rickel, of Seymour, heads the Institute of Invasive Bamboo Research, which calls yellow groove bamboo "the worst alien invader that the USA has ever encountered." There are related varieties that are nearly as bad, she said.
Rickel's group is trying to get bamboo banned in Connecticut. Her infestation was severe enough to convince Seymour's Board of Assessment Appeals to reduce the assessed value of her home by about 13 percent.
"The shoots grow right through asphalt," she said. "The plant is exponential. The first two or three years isn't bad, but by year five it's a problem. By year 10 or 15, it's taking out your whole street."
Another horror story came from Robin Arcarese, of Bozrah, in eastern Connecticut.
"Just this spring, I was pulling into my driveway and I said to myself, `What's that growing out of my roof?' " she said. "It was my neighbor's bamboo, which had grown behind my siding and out the roof."
Not an 'invasive'
Despite bamboo's almost unearthly growth rate, it's not on the state's list of invasive species, nor is it likely to be anytime soon, experts say.
This is because, although it's a huge headache for some homeowners, it doesn't seem to be attacking natural habitats to any significant degree, and its effect on native plants and animals is almost nonexistent.
"Right now, bamboo isn't meeting enough criteria to be considered as even potentially invasive," said Donna Ellis, senior extension educator and co-chairwoman of the Connecticut Invasive Plant Working Group. "This is not to say that it isn't causing problems for homeowners, particularly along property lines, but because of the nature of where it's growing, it's not posing a threat to the natural habitat."
There are more than 100 plants on the state's list of invasive plants, many of which you see every day, from the Norway maple to the beach rose. It's illegal to cultivate, purchase, sell or transplant any of those plants.
Still, yellow groove bamboo has been banned or limited elsewhere, including in several communities in Delaware, New York, Maryland, Pennsylvania and Florida and even in Australia. In 2011, Sag Harbor, N.Y., enacted a ban, but it was quickly repealed.
A neighbor problem
"The problem isn't with bamboo, it's with neighbors," said Mike Johnson, who grows bamboo professionally at his Summer Hill Nursery in Madison, which sells plants wholesale to nurseries and garden centers.
Johnson said that whenever he sells bamboo, he makes sure that the buyers are aware of what they're dealing with.
"I also sell the barrier to them at cost," he said. "But when you mention `barrier,' some people won't hear of it. I've had cases in which people have said, `I don't want a barrier -- I just want to get back at my neighbor.' "
Indeed, in East Lyme, Daniel and Sally Wade are in a long-running spat with a neighbor. While neighborly disputes are common everywhere, the Wades are dealing with a growth of bamboo that the neighbor planted along the property line.
"He planted this thing as a weapon to destroy our property," Daniel Wade said. "Then he installed a rhizome barrier on his side of the bamboo, but not on ours."
Johnson said that when properly handled, bamboo is a beautiful plant that creates an inexpensive and fast-growing privacy screen. He said that his sales have doubled since stories about the bamboo infestations began appearing in the news a couple of years back.
"The barrier that we sell is 60 mil (1.5 mm) high density polyethylene plastic sheet that goes down 30 inches," he said. "The rhizomes aren't going to get through that."
Experts say that to be effective, the semirigid plastic barrier, which comes in rolls of up to 130 feet, must completely encircle bamboo plantings. Installation is a job for the professional, particularly in the rocky, root-crossed soils found in Connecticut. A full-size power shovel is recommended.
"Any time neighbors don't cooperate, you'll have problems," said Ward, comparing bamboo to infestations of zoysia grass, another import from Asia that has pitted neighbor against neighbor.
Knocking it back
The sooner a bamboo infestation is attacked, the better.
In Woodbury on Thursday, Ward was with a crew of his fellow Experiment Station plant scientists to conduct an early morning attack on an eighth-acre stand of yellow groove in a town park. After about 45 minutes, the growth surrendered to their power brush cutters. But Ward said that the stand will need continued treatment and monitoring in the next year or so before victory will be complete.
"We'll come back out here again in June to cut it down again, and we'll probably have to spray it in the late summer."
Ward said that to be effective, a herbicide such as Scott's Roundup has to be applied in the late summer. This is when the flow of nutrients in plants switches from up to down.
"Some people say that this strategy won't work," Ward said. "But other people say that it does work. I don't have a horse in this race, I'm just trying to find out the most cost-effective way to deal with this plant."
The other option, and far more expensive, is to dig out the rhizomes with a power shovel. This entails sifting through the dirt to extract all of the rhizomes and burning them so as not to be left with a pile of soil that will cause another infestation.
Another complication is that bamboo problems are usually along property boundaries, which means stone walls, fences, driveways, sewer pipes, water lines and such are often in the way of digging.
The Experiment Station is growing bamboo at all three of its farms to determine growth rates and control methods.
firstname.lastname@example.org; 203-330-6403; http://twitter.com/johnburgeson