The Jerusalem artichoke, a nondescript weed used mainly as hog feed, is attracting new attention as a means of fueling America's fleet of gas hogs. Given an annual rainfall of 11 to 12 inches, the Jerusalem artichoke can produce more than three times as much alcohol as corn, currently the prime source of alcohol for fuel.
The Washington State Gasohol Commission has applied for a $390,000 grant from the US Department of Energy to study making alcohol from Jerusalem artichokes.
It is one of hundreds of such applications seeking a part of the $3 billion the federal government proposes to spend to stimulate gasohol production.
Despite its name, the Jerusalem artichoke bears little relationship to the table variety. It is a cousin of the sunflower and its name came in a round-about way from "girasol," the Spanish word for sunflower.
A tuberous-rooted plant, the jerusalem artichoke grows a leafy stalk from six to nine feet tall and can be grown virtually anywhere in North america. people who grow Jerusalem artichokes in gardens usually use a plant container because "once it takes hold, it is very difficult to get rid of -- like bamboo," says Tom Clark of Vitro Engineering Company, which is doing the Washington feasibility study.
Until recently, the plant was held in such low regard that Mr. Clark has had to go back to US Department of Agriculture studies from the 1920s and 1930s to find out much about it.
Those early studies showed that, with a foot of rainfall, yields of 20 to as many as 60 tons per acre are possible. that translates into roughly 1,000 gallons of alcohol an acre, he says.
But even if there are only three inches of rain -- a condition in which crops such as corn or potatoes are wiped out -- five to eight tons of Jerusalem artichokes per acre are still possible, according to Mr. Clark.
Unlike potatoes, which also have a high potential for production of alcohol, Jerusalem artichokes require relatively little fertilizer and can be grown on marginal land. That means many plants can be grown for fuel without sacrificing prime food-producing land, says Mr. Clark.
In fact, the Washington Gasohol Commission hopes to grow the plant on rocky "scabland" in the eastern part of the state, hand-seeding the land without plowing, and then harvesting the stalks.
At the moment, however, scientists are not sure there is enough sugar in the Jerusalem artichoke stalk to make such a harvest worthwhile or whether the stalks can be harvested without killing the tubers.
Typically, sugar concentrates in the stalk during the summer and migrates back into the tubers in the fall to regenerate the plant.
Mr. clark said he is approaching Jerusalem artichoke-farming as an integrated system, whereby the plant is grown and harvested for its sugar content and distilled into alcohol and the residue is fed to cattle -- as in Europe and China.
The Jerusalem artichoke lends itself to relatively small-scale gasohol production plants because the sheer mass of the plant prohibits extensive transportation. Small gasohol plants generally are considered to be those that produce 1 million to 2 million gallons of alcohol a year.
In this respect, the artichoke is similar to sugar cane, which Brazil is using to produce alcohol for automobile fuel. In time, it could come to be considered the North American equivalent of sugar cane, some scientists say.
Mr. clark envisions farmers with about 1,000 acres of Jerusalem artichokes forming a cooperative to build an alcohol plant.
The gasohol commission favors small- scale gasohol production despite a much- disputed report by the state Department of Commerce and Economic Development that such operations are not yet economical. The study concluded that, to be economical, a plant would have to produce about 50 million gallons of alcohol.
Two corporations are seeking federal funds to build such plants at a cost of about $70 million each. If completed, they would be the largest alcohol-producing plants in the US.