Attack of the Giant Grass!

AP Photo/Allen Breed

Arundo donax towers over the tallest man's head. It's thick, bamboo-like, and three-stories tall. It can withstand cold, and it can withstand drought. Give it water, and a little nitrogen, and it grows. Fast.

Killing it can be difficult. In California, where it was introduced in the 1800s, Arundo has gotten so out of control that in some places it seems to be the only plant growing on the riverbanks. It doesn’t have seeds, but it doesn't need them: it has other methods of multiplying. A fierce rainstorm can tear up its shallow roots and spread them far downstream. There, they start growing all over again.

Mow it down, spray it with pesticides—it’s all futile. If any of the monstrous reeds are left upstream, they'll grow back. Arundo doesn't need to be near water to thrive, though. It grows pretty much anywhere. It grows in Oregon, Arizona, Texas, Missouri, Georgia, Florida, Maryland, Virginia—down the West Coast and across the broad swath of the southwest and southeast, up into the mid-Atlantic. Often it remains in small stands, growing tall, but staying in one place. But sometimes, it takes over and becomes an invasive species—an expensive problem for humans and a mortal threat for plants and animals.                       

Energy companies, however, are set to make Arundo one of the stars of the biofuels industry. They think they can control it. They're willing to take the risk. But not everyone is so sure it's worth it. If the companies fail—if Arundo does get out—it could have irreparable consequences.


In Mills River, North Carolina, up in the mountains and not far from Asheville, a small plot of Arundo has been growing since 2008, alongside switchgrass and another unusually tall plant called giant miscanthus. This patchwork of grasses was planted as part of a study on crops that could feed a next-generation biofuel plant. The qualities that make Arundo frightening to people who've dealt with it as an invasive—its size, sturdiness, and quick growth—make it attractive to the biofuel industry. Although it's not the only biofuel crop North Carolina is looking to grow (or the only one that's considered invasive elsewhere in the country), it does have the potential to yield the most biomass per acre—a key metric to making next-generation biofuels financially feasible.

"It's the difference between having this industry work or not work," says Matt Harrod, a director at Chemtex International. An Italian-owned polyester fiber, plastics, and design technology company, Chemtex has dipped into the biofuels market, and worked with liquefied natural gas, as well. Last year, in Crescentino, Italy, the company started up the world's first commercial-scale plant to make ethanol from plants like Arundo instead of corn or sugar cane. The company's also part of a joint venture that invested $200 million in developing a process to make this sort of cellulosic matter a cost-effective source for biofuel. Now, Chemtex wants to bring that same process to America, and has spent almost a million dollars lobbying the federal government over the past two years.

Over the summer, the company announced it would receive federal-loan guarantees worth $99 million to build the United States's first commercial-scale cellulosic biofuel plant in eastern North Carolina. Not long before, in spite of the objections of national and state environmental groups, the Environmental Protection Agency (EPA) added fuel made from Arundo to the Renewable Fuel Standard. (This is the policy that incentivizes the creation of biofuels and requires their use in the country's cars and trucks.)

Environmental advocates and scientists who have been dealing with Arundo as an invasive species think that the biofuels industry’s bet that this plant can be controlled is a bad one. More than 100 groups wrote to the EPA arguing against approving Arundo as a biofuel crop. "The last thing we need are government-sanctioned economic protections for an industry reliant on pests as their raw product," Mark Newhouser, of the Sonoma Ecology Center, wrote me. "This is just common sense."

For years, the biofuel industry has been chasing the advantages of developing plants like Arundo as biofuel crops. And while there's reams of research on different sources and strategies for creating cellulosic biofuel, the industry has had little success scaling that research up into a commercial enterprise. If "energy grasses" are proven a financially viable feedstock, the crops that feed ethanol plants could be grown on marginal land, with less chemical fertilizer than corn. The amount of land needed to meet the government's renewable-fuel goals could shrink, too. But growing a crop like Arundo on an agricultural scale is the botanical equivalent of adopting a wolf. Most agricultural crops are like dogs: we’ve spent thousands of years domesticating them; we know, more or less, how they behave; we can control them. Like a tame wolf, Arundo might seem like it’s behaving well now, but there’s an inherent danger in having it around.

"We haven't talked about doing something on this scale in this time period since the invention of agriculture," says Jacob Barney, a professor of invasive-plant ecology at Virginia Tech University, who's studied these grasses. Corn has been bred for 10,000 years to grow only where humans plant it. Arundo's been bred for only a fraction of that time. "It's a wild thing," Barney says.

To the industry, ultimately, planting Arundo is about saving money. Higher yields per acre mean they have to spend less on land. Chemtex plans to contract with farmers to grow 18-19,000 acres of biofuel crops, according to Harrod, the Chemtex director. So far, he has about half of that accounted for, with switchgrass and biomass sorghum. Adding Arundo to the mix could help keep Chemtex’s costs down.

“Biomass sorghum is a quick growth annual. You can plant it in late March or early April and have it ready in July. Switchgrass can come online in September and works well through the fall,” says Harrod. It costs less for a company like Chemtex to run a biofuel plant if it can take crops directly from nearby fields, year-round, without having to bale and store them. “Arundo—they store themselves well in the field. They stand very well. They don't fall, and they maintain a lot of their leaves,” Harrod explains. “So it fills those winter months from December to February that other crops can't do.”

In southeastern North Carolina, the land that’s most likely to be converted to fields of energy grasses is currently growing bright green, knee-high Bermuda grass for cow forage. But one day soon, you could driving down the same country road by these same fields and all of a sudden start feeling a little like Rick Moranis in Honey I Shrunk the Kids, with fields of grass stretching far above your head.


It's difficult to predict if a species will become invasive in any particular place. But once it does it’s almost impossible to stop its spread. California has spent tens of millions of dollars trying to get rid of Arundo, and across the country, invasive species cost the economy a total of $7.7 billion in eradication costs and lost agricultural productivity. Many of these plants were planted by well-intentioned people for good reasons.1 1. Kudzu, the most commonly cited scare story, was originally intended to provide shade and prevent soil erosion; it has taken over millions of acres of land. (There's been some interest in using kudzu as a biofuel stock, as well.).

Arundo hasn't been a problem in many of the states where it's been planted as an ornamental, or as a building material. "We don't really have good data on why Arundo is not invasive in areas like Florida and South Carolina," says Adam Lambert, a research biologist at University of California-Santa Barbara. But that doesn't mean it never will be. Many weeds have a “lag phase” where, for a long time, they’re not a problem, until they reach some unknown, critical. Then, says Lambert, “they just start taking off.”

At that point, the plants become much, much more expensive to deal with. There is a federal state-by-state noxious-weed directory, which could, in theory, help prevent invasive species from being planted or from spreading: no one is allowed to grow or transport the plants on these lists. But they are created according to political, rather than scientific, logic. “Governments are not basing decisions about "noxious" weeds on what the science is—what weed ecologists think of as noxious or invasive,” says Bryan Endres, a law professor who’s studied the regulation of invasive species. He, along with Jacob Barney, the Virginia Tech scientist, worked on a study that showed that there was little correlation between plants that scientists would classify as “invasive” and plants that are regulated. “The question is why?” says Endres. “The power in the legislature traditionally is in the agricultural community. Plants that have been a problem for agriculture have been classified as noxious weeds. If it's not a problem to agriculture, then the state doesn't see any reason to regulate.”

The little regulation that does exist is inconsistent. Maryland has six plants on its noxious-weed list. None of those plants are on Virginia’s list. California has listed Arundo as a noxious weed. So have Texas, Hawaii, and Tennessee. Fourteen states consider it invasive. Environmental groups pushed for North Carolina to add Arundo to the state's noxious weed list, but earlier this year, the state's Board of Agriculture denied their petition. The state government has long been promoting the biofuel industry; the board said that Arundo could be grown “responsibly,” as long as proper management practices were in place.

Right now, the federal government is paying scientists to figure out how make Arundo grow even bigger and faster while simultaneously paying other scientists to figure out how to eliminate it. Lambert’s lab is collaborating with the USDA’s Agricultural Research Service to find a biocontrol agent for Arundo—a bug or a fungus that naturally keeps it in check. In the long run, using biocontrol is cheaper than continuing to plow money into chopping Arundo down and spraying it with pesticides.

Like Arundo, though, these “agents” are wild things. “Once you release them, you can't get them back,” says Lambert. If these scientists find the right insect and release it in California, there’s no guarantee it won’t make its way across the country, to fields where Arundo’s being grown as a biofuel, and decimate those crops. Scientists who do this work worry that the biofuel industry’s interest in Arundo will create political heft that weighs against their own work. Given the money Chemtex has already spent on lobbyists, it’s not an unjustified fear.

If farmers do plant Arundo in large quantities, they’ll need to follow a protocol that minimizes the risk of the plant spreading—plant only in certain places, leave a border around the field, cover trucks transporting plant material, destroy any plants left if the project fails. “There’s no such thing as a risk-free anything,” says Jacob Barney, who helped develop this regime. “It's all about understanding what the risk is and mitigate that risk to the greatest degree possible.”

This is the story of every form of energy—new or old—that the country is pursuing right now. Fracking horizontal wells is riskier than drilling vertical ones. Deepwater oil drilling has dangers that traditional techniques did not. But within these regimes, some energy sources are riskier than others: tall turbines might kill birds and bats, but they’re not going to spill wind all over the countryside. If the country is going to stop using cheap, polluting fuels like coal and oil, energy suppliers need to choose the least bad option; the alternative is relying on even riskier and more destructive strategies, like mining tar sands, to produce traditional fuels. Biofuels are clearly on the less-bad side, and there's a need for them to fuel vehicles, like planes, that can't easily run on electricity. And everyone agrees that it's important for the industry to figure out how to use less-resource intensive cellulosic feedstocks instead of corn or sugar cane. Environmental groups that worry about invasives argue, simply, that there are plenty of energy grasses to choose from: biofuels companies should limit themselves to crops that don't have a history as problem children.

No matter what precautions the industry takes, it’s impossible, in the short term, to eliminate the risk of invasiveness for a crop like Arundo . Controlling wild things, even plants, is an unpredictable business. If this were a horror movie—Invasion of the 30-Foot-Tall Monster Grass!!—where Arundo moved in and took over, only to be killed off, cut to the ground, and sprayed with heavy-duty pesticides, it would end with a shot of a single sprout of the plant, making its way out of the soil. In the sequel, the plant will have learned to grow seeds.

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