Miracle plant or kudzu?

States see reed a bit differently

Farming Director Sam Brake of the Biofuels Center of North Carolina in Oxford is dwarfed by a stand of Arundo donax in a test plot in Oxford, N.C.
Farming Director Sam Brake of the Biofuels Center of North Carolina in Oxford is dwarfed by a stand of Arundo donax in a test plot in Oxford, N.C.

— It’s fast-growing and drought tolerant, producing tons of biomass per acre. It thrives even in poor soil and is a self-propagating perennial, so it requires little investment once established.

However, many are comparing Arundo donax, also known as “giant reed” and which can reach heights of 30 feet in a single season, to another aggressive Asian transplant: the voracious kudzu vine.

To people in the renewable fuels industry, Arundo is nothing short of a miracle plant. An Oregon power plant is looking at it as a potential substitute for coal, and North Carolina boosters are salivating over the prospect of an ethanol biorefinery that would bring millions of dollars in investment and dozens of high paying jobs to hog country.

But to many scientists and environmentalists, Arundo looks less like a miracle than a nightmare waiting to happen. Officials in at least three states have banned the bamboo-like grass as a “noxious weed”; California has spent more than $70 million trying to eradicate it. The federal government has labeled it a “high risk” for invasiveness.

In October, more than 200 scientists sent a letter to the heads of federal agencies including the Environmental Protection Agency and the Departments of Agriculture and Energy, urging them not to encourage the commercial planting of known invasives like Arundo.

“Many of today’s most problematic invasive plants - from kudzu to purple loose strife - were intentionally imported and released into the environment for horticultural, agricultural, conservation, and forestry purposes,” they wrote. “It is imperative that we learn from our past mistakes by preventing intentional introduction of energy crops that may create the next invasive species catastrophe particularly when introductions are funded by taxpayer dollars.”

Mark Conlon, vice president for sector development at the nonprofit Biofuels Center of North Carolina in Oxford, hates the comparison with “the weed that ate the South.”

“There’s no market for kudzu,” says Conlon, who is among those promoting a proposed $170 million, 20 million-gallon-a-year ethanol project here - and Arundo’s role in it. “There’s no reason to manage it. It was thrown out in the worst places you can think of and left there.”

His message about Arundo: It’ll be different this time. We can control it.

But Mark Newhouser, who has spent nearly 20 years hacking this “nasty plant” from California’s riverbanks and wetlands, has his doubts.

“Why take a chance?” he asks.

The North Carolina biofuels center’s staff has explored a variety of biofuel raw materials, from food crops such as corn, sugar beets and industrial sweet potatoes to cottonwood and loblolly pine trees. Even pond scum - or duckweed. All were either hard to raise in quantity, too expensive or more valuable for other uses.

The staff also studied so called “energy grasses” - giant Miscanthus, coastal Bermudagrass, switchgrass. Out behind the center, Farming Director Sam Brake planted test plots of four varieties of sorghum.

But for hardiness, ease of cultivation and maintenance, and yield per acre, none comes even close to Arundo donax.

Believed to have sprung from the Indian subcontinent, Arundo has spread around the globe. Europeans have been using it for centuries in the production of reeds for woodwind instruments.

Like kudzu, which came to the United States as part of Japan’s exhibit at the 1876 Centennial Exposition in Philadelphia, Arundo arrived here in the mid- to late 19th century. And also like kudzu, Arundo was once touted as a perfect crop to help stem erosion. In California and Texas, farmers, ranchers and government workers enthusiastically planted it along waterways and drainage ditches. Shallow rooted, the canes would break off and move downstream,starting new stands.

Arundo has become “naturalized” in 25 warmer-weather states, according to a USDA weed risk analysis released in June.

In banning it, California, Nevada and Texas have said the plant crowds out native species and consumes precious water.

The Tennessee Exotic Pest Plant Council lists it as a “Significant Threat.” Virginia officials have labeled it “moderately invasive.” The West Virginia Division of Natural Resources has categorized the giant reed as “occasionally invasive.” But that might change if it were to be promoted as a commercial crop, says Elizabeth Byers, a vegetation ecologist with the agency’s wildlife diversity unit.

“I certainly wouldn’t want to see any invasive species used as biomass,” she says. “Because they can escape.”

North Carolina is keeping an eye on Arundo, but the folks in Oxford say past need not be prologue.

In terms of yield, Arundo far outpaces the competition - up to 20 dry tons per acre, versus 3 to 6 tons for Bermuda.

So planting Arundo would require far less land to supply Chemtex International’s fiber needs. Chemtex, which operates a commercial-scale cellulosic ethanol plant in Italy, wants to break ground on a similar plant in North Carolina by mid-2013 which could employ more than 60people.

The problem is Arundo may not be as efficient as its less vigorous rivals at absorbing nitrogen.

“If it’s not, it’s not where we need to be on the swine farms,” said David Crouse, a soil scientist at North Carolina State University.

So far, yields from North Carolina test plots have averaged from 5.8 dry tons per acre at the Oxford site to just over 11 tons in the sandy loam soils in which most Chemtex suppliers would be planting, though NCSU soil scientist Ron Gehl notes these are not yet “mature stands.”

In January, the EPA gave Arundo preliminary approval under the federal renewable fuel standard program - meaning producers could qualify for valuable carbon credits. When environmental groups complained that the decision was at odds with an executive order aimed at preventing the spread of invasive species, the agency agreed to re-evaluate the crop.

Without the EPA’s renewable fuels designation, Arundo would be less profitable to grow. And without Arundo in the mix, says Conlon, “I would be greatly concerned” about the Chemtex project - and the state’s grand plans.

W. Steven Burke, president and chief executive officer of the biofuel center, said Arundo has been sold in the state for years as an ornamental. To him, it’s a no-brainer as a biofuel source.

But EDF Southeast Director Jane Preyer wonders if a hurricane-prone state like North Carolina is the smartest place to grow such a crop on so large a scale.

In 1999, Hurricane Floyd caused widespread flooding that put much of eastern North Carolina under several feet of water.

Business, Pages 73 on 11/18/2012

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