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In an Orwellian distortion of what it means to be “green,” a subset of the modern environmentalist movement is embattled in a bitter war against a handful of despised species of plants and trees. The enemy, like al Qaeda, seems to be everywhere at once, and often resembles a single giant, global organism of cloned pod cells than billions of individual plants. Saddled with the derogatory term “invasives,” these interlopers from foreign lands – the botanical version of the illegal alien – are accused of pilfering space and sunlight from our shy, purebred, less aggressive domestic varieties. Phragmites, purple loosestrife, Japanese knotweed, autumn olive and English ivy; these are just some of the enemies of these new homeland security-style environmentalists. Their weapons: clear-cutting, burning, and chemical and biological warfare, engaging the enemy by air, land and sea.
The New York State Department of Environmental Conservation (DEC) in November of last year announced that more than 30 municipalities and organizations around the state would be granted around $1.4 million to help wipe out infestations of what it terms “non-native aquatic species” across the state. Local beneficiaries of the state’s new environmental largesse include the Eastern New York Chapter of the Nature Conservancy, which stands to collect upwards of $30,000 to effect the eradication of 94 acres of purple loosestrife and phragmites (common reeds) from “calcareous wetlands in Dutchess County,” and Scenic Hudson’s Land Trust, slated to get around $14,000 to decimate insidious stands of bamboo-like Japanese knotweed from the Esopus Meadows Preserve in Ulster County.
It is important to note that the relatively rare sorts of wetland of which purple loosestrife is so fond is also home to all sorts of rare flora and fauna, including the federally listed threatened bog turtle and several groups of hard-to-find insects. Unusual plant species associated with these wetlands include handsome sedge, blunt spikerush, Torrey’s bulrush, hemlock-parsley, blazing-star, Virginia bunchflower, swamp birch, larger Canadian St. John’s wort, spreading globe flower, hoary willow, marsh valerian and Schweinitz sedge.
Troy Weldy of the Nature Conservancy, a worldwide organization dedicated to using a “science-based approach” called Conservation by Design to “preserve healthy ecosystems that support people and host the diversity of life on Earth” such as the explosive cornucopia of rarities noted above, has this to say about the approach his organization employs vis-à-vis invasive species: “Herbicides are one of the tools in our toolbox; we wouldn’t be able to do our work without them.”
As is often the case in war, friend and foe are hard to tell apart. In many cases it takes a scientist to distinguish between native and non-native species. The endangered Indiana bat, for instance, is so similar to the common brown bat that the major difference is the length of its toe hair. Interestingly, one of the reasons that it is endangered at all is exposure to pesticides.
Purple loosestrife, home of the American goldfinch
The evil spawn that is purple loosestrife is a tall, beautiful plant crowned with a flowing mane of purple flowers, as the name implies. It may have arrived from Europe, Asia or Africa aboard ships 200 or possibly as many as 400 years ago. It is said to be a natural remedy for diarrhea and dysentery. Scientists are not united as to whether purple loosestrife is a danger to the ecosystem and this area of study is relatively young, but there is one man who has been studying this particular plant for more than 35 years. Dr. Erik Kiviat, executive director and co-founder of Hudsonia, a nonprofit environmental research institute that educates and provides technical assistance in the environmental sciences (www.Hudsonia.org), says purple loosestrife provides food, shelter and hunting ground for many animals including birds, bees and small mammals. A 2004 study in the Canadian Journal of Botany unexpectedly concluded that plant diversity was actually higher in invaded than in un-invaded areas.
Defining what is “invasive” is tricky in the first place. How large a swath of real estate do you include in your study? Just the stand of loosestrife, or the other adjacent areas where it hasn’t colonized? Is a blueberry patch a growing monoculture of aggressive blueberries? Is a cherry tree the start of a cherry invasion? Berry plants certainly spread like invaders. Is it that the grasses in question are recent arrivals, like Lou Dobbs’ “aliens?” There seems to be a social and aesthetic component to the demonization of recently introduced plants and trees that doesn’t necessarily correspond with actual danger. Unlike corn – a species of grass not native to the U.S. that grows in toxic monocultures – nobody makes money from purple loosestrife. There is no payoff for saying good things about it.
In fact, it’s just the opposite: government grants are available. It actually pays to kill this immigrant. The Nature Conservancy for example, the trademarked motto for which is: “protecting nature, preserving life,” is slated to get a $30,533 grant from the state DEC to join the regional War on Shrubbery.
Bio-weapons
So back to the toolbox. How do you kill a weed to protect the birthplace of the Hudson River School of painting, not to mention the American environmental movement, from an alien scourge? Unlike an organic gardener, you don’t just pull it; you turn to an arsenal of biological weapons, or “control agents” in eco-speak. The Nature Conservancy, in cooperation with researchers at Cornell University, is turning the tables on their own mission by introducing another invasive species to eat the loosestrife. Beetles and weevils imported from Europe have been let loose in stands of purple loosestrife to eat their hearts out (the hearts of the loosestrife; they like it). Scientists at Cornell assure us that they’ll cause no harm. Ever. And in fact, no documentation of those vermin causing problems has been documented to date.
On the other hand, it took almost 200 years after its introduction for purple loosestrife to be seen as a problem. What future generation might have a problem with the beetle, once it’s run out of loosestrife hearts to nosh on? Dr. Kiviat warns of the future of the introduced beetles (gallurcella). “One has to assess the likelihood that they will evolve and change after their release, because insects do this all the time in nature. It’s very common for insects to evolve and change and switch host plant to a different type.” In fact, just like the beetle, many “invasive” species were purposely imported by agricultural scientists to combat a perceived problem – such as African honeybees, which were brought to this continent to increase honey production.
Chemical weapons
It’s not just biological weapons that will be engaged in the battle against the spreading purple plague. Chemical weaponry will also be employed to tackle the “worst infestations.” Specifically it will be glyphosate, by Monsanto, the active ingredient in the herbicide Roundup, which inhibits the production of that famous chemical tryptophan, an essential amino acid in the human diet that is often blamed for sleepiness at Thanksgiving. The federal Environmental Protection Agency (EPA) reviewed the toxicology of glyphosate in 1993 and found it to be non-carcinogenic. The EPA also found that there was no evidence of cardiovascular harm from the toxic cloud hanging in the streets of lower Manhattan following Sept. 11.
Employees of the Nature Conservancy interviewed for this article felt they would not be at risk from the poison because they are qualified and would be reading and following label directions and using the herbicide sparingly. That is a good thing, since three studies (De Roos et al. 2003b; Hardell and Eriksson 1999; Hardell et al. 2002; McDuffie et al. 2001) suggested an association between glyphosate use and the risk of non-Hodgkins lymphoma among those who apply the chemical.
A recent study done at the biochemical lab at Caen University (Laboratoire de Biochimie et Biologie Moleculaire, USC-INCRA, Université de Caen, Caen, France) found that “Glyphosate is toxic to human placental JEG3 cells within 18 hours at concentrations lower than those found with agricultural use.” And if you think French academics are just alarmists scared of their own shadow, consider the government of Afghanistan, which despite being awash in problems found the time recently to refuse to allow the U.S. to spray glyphosate from the air in their country to destroy poppy crops, “because of fears about the herbicide glyphosate’s effect on the environment, other smaller crops, and (human) health,” according to a December 2007 report by The Guardian Unlimited, the online presence of the British newspaper The Guardian.
Closer to home here in the Hudson Valley, Cornell University, the institution that introduced the root-boring beetle on this continent for the first time, describes glyphosate as a “broad-spectrum, non-selective, systemic herbicide.” That is, it kills essentially “all annual and perennial plants including grasses, sedges, broad-leaved weeds and woody plants – and is slightly toxic to wild birds.”
Xenophobia for greenies
Phragmites, a.k.a. the “common reed,” is slated for destruction by the Nature Conservancy as well. Not the native common reed; just the foreign common reed. If you have trouble telling them apart, don’t feel bad; most people can’t. And don’t bother looking for toe hairs; until recently it took a DNA test to differentiate the two. Ask Dr. Kiviat; he says it’s very difficult and he has 40 years in the field, literally.
Climate change and rising levels of CO2 may play a part in the spreading of some species of grass, in which case they may be Earth’s way of adjusting to the new climate. Fast-growing grasses eat up and sequester carbon quite nicely. Killing a few stands of reed may be counterproductive.
As a core tenet of its mission, the Nature Conservancy has chosen what they consider to be special areas of unique and diverse plant and animal life that are endangered. Treating them will preserve some unique areas of biodiversity. I spoke about this with two employees of the Nature Conservancy in the Pine Bush of Albany, who mentioned another species designated for annihilation. “This is black locust,” one said, pointing to a stand of healthy 20-year-old trees. “We’ll be removing (killing) them.”
The Pine Bush is indeed a unique environment. Mostly scrub pine trees grow there, along with some scrub oak, which is not considered invasive. But still, it’s called Pine Bush – not Pine and Black Locust Bush. For landlocked Albany, it’s a unique ecosystem that looks for all the world like an oceanfront dune area. It’s an area of deep sand laid down in eons past in a vast glacial lake, and through which water now drains so fast that many plants and trees native to the region die of thirst. The scrubby pines that grow in the sand are considered “native” only because they have out-competed other trees and plants in the area – but they’re not native to Albany. You may have seen them on Cape Cod, Martha’s Vineyard, Nantucket or in the New Jersey Pine Barrens, where they’re common. But in Albany they’re unique, and everything else must die. Black locust is native in places as close as West Virginia, but in Albany it’s a recent arrival, most likely planted behind a long-since forgotten house as a lightning rod. That’s what people did. You could make the argument that the Pine Bush would be more diverse with a few black locusts in it.
Bio-ethnic cleansing
Meanwhile, over in Ulster County, Poughkeepsie-based Scenic Hudson has been awarded a DEC grant of $14,000 to poison a plant called Japanese knotweed in the Esopus Meadows Point Preserve and Environmental Center, which it says is “one of the Hudson River’s most important spawning grounds for striped bass.” Japanese knotweed is an exceedingly fast-growing edible plant that is native to Asia, just like rice. Scenic Hudson will match the $14,000 grant with $14,000 of its own money, and the combined total will be used in the Esopus Meadows Preserve to temporarily eradicate the Asian immigrant ornamental, which is found all over the Northeast. Japanese knotweed is also known as “Sally rhubarb,” because it tastes like rhubarb, which is also an Asian immigrant and a frequent colonizer of riparian (meaning “likes to grow near river”) ecosystems. Japanese knotweed is apparently an especially good source of resveratrol, an antibacterial, anti-fungal substance also found in the skin of red grapes (and red wine!) that is often sold in pill form as an antioxidant.
This has been a big year for resveratrol, which may be gaining respect in academic circles. Fortune magazine in January profiled a startup company Sirtris, run by Harvard M.D. Christopher Westphal, who along with consultant Phillip Sharp, a Nobel laureate biologist and MIT professor, claimed to have found that resveratrol increases metabolism, protects against obesity and increases stamina in mice. A study sponsored by the National Cancer Institute and the University of Michigan Cancer Center looked at preventing cancer through the use of resveratrol in humans, and a study at the department of cancer biology at the University of Texas concluded: “We hypothesize that resveratrol may be especially suitable as a lead agent for prostate cancer prevention.”
Scenic Hudson, however, is not attempting to determine the possible beneficent uses of Japanese knotweed. The organization is primarily concerned that knotweed will crowd out native species of flora and fauna and allow erosion of their eminently hike-able Hudson riverfront in the Esopus Meadows Preserve. The organization says a small section of beach at the meadows has been eroding over the past few years.
Countering Scenic Hudson’s assumption, however, is Catherine O’Reilly, assistant professor of biology at Bard College, freshwater ecology specialist and contributor to the United Nations Climate Change Panel that recently won the 2007 Nobel Peace Prize, who thinks the cause of erosion on the Hudson’s shores is the documented rise in the average level of the river due to climate change.
The irony is that Japanese knotweed is known for slowing erosion, and has in the past been used for just that purpose. A quick check of the National Agricultural Library turns up a number of descriptions of knotweed as effective in reducing soil erosion, including these:
• “Roots are present along the rhizome and can extend quite deeply into the soil, making knotweed effective in preventing erosion;”
• “This perennial plant is difficult to control because it has extremely vigorous rhizomes that form a deep, dense mat.”
In addition, fast growing plants like Japanese knotweed consume and store planet-warming CO2, and killing them releases it, which may add ever so slightly to the original problem.
At any rate, with its $28,000, Scenic Hudson, like the Nature Conservancy in Dutchess, will employ the herbicide glyphosate to destroy its enemy. In this case, the organization will be spraying and injecting the stuff on the banks of the Hudson in the Esopus Meadows Preserve. Glyphosate is known to grab onto soil and not let go, which is an advantage when using it on the banks of the Hudson, since less of it is likely to be dispersed in the river, which supplies drinking water for Hyde Park, Poughkeepsie, Rhinebeck and Newburgh, among a growing number of places. To further protect the river, Scenic Hudson plans to apply the herbicide sparingly and at low tide.
One of the people who may be doing the application is Chris Kenyon, parks manager for Scenic Hudson and former park ranger for the National Park Service, who allows that the war against Japanese knotweed is a losing one. “I am confident that we will be able to eradicate the approximately one-acre stand that we have here, but it’s growing right up along the sides of the road and it’s only a matter of time before it gets re-introduced here and it can come back,” he concluded. “It’s here in the valley; it’s here to stay.” However, the knotweed should be absent from that acre at least until 2011 since the DEC grant will allow Scenic Hudson to repeatedly treat the area for three years.
Indicating the beach area that Scenic Hudson believes has receded due to the knotweed, Kenyon pointed out a small building used by Clearwater, the famed environmental group. “Clearwater has their environmental education center in that building there and they run education programs throughout the year here and they have school kids go out in the river with seine nets and sample what’s in the river, and this beach location is one of their prime spots for their education programs. So we’re hoping that they’re going to educate the students on what we’re doing here and teach them about invasives, so that they can go back home and share this with their families and maybe will help (prevent) future infestations of it by spreading the word that you shouldn’t plant this (Japanese knotweed) in your back yard.” However, the star of that lesson may be absent for the next three years.
Interestingly, the DEC grant will allow Scenic Hudson to abandon their previous technique of planting trees surrounded by shade cloth to discourage the growth of the knotweed, which thrives in direct sun but doesn’t grow in shade.
To find a great recipe for apple & knotweed pie, see: http://www.wildmanstevebrill.com/Web%20Recipes/Apple%20and%20Knotweed%20Pie.html.
Be careful, of course, not to use any knotweed from the Esopus Meadows Point Preserve.
