A growing ethanol industry is sure to have a significant impact on land use and availability in the United States, according to researcher Harold Collins, USDA-ARS, Prosser, Wash.

Speaking at the National Alliance of Independent Crop Consultants annual meeting in Seattle, Collins provided a short-term look to 2010, when ethanol production is projected to climb to 15 billion gallons annually, and a long-term outlook to 2016, when projections for ethanol production could hit 32 billion gallons annually.

Citing information from the Center for Agricultural and Rural Development at Iowa State University, Collins noted that current ethanol capacity from 131 ethanol plants in the United States is about 7 billion gallons per year. The total capacity after projected expansion to 2010 is for another 7 billion gallons of ethanol coming from 73 new plants and 10 expansions in current plants.

Longer-term, corn ethanol production is projected to approach 25 billion gallons by 2016, with some estimates as high as 32 million gallons.

In terms of bushels, in 2007, 2.2 billion bushels of corn were used to produce ethanol. This is projected to rise to 3.5 billion bushels in 2008. In terms of acres, ethanol required 23 million acres of the 94 million acres of corn planted. Thirty-nine million acres went to the feed industry, while 14 million acres were exported.

Increases in ethanol production from today's 13 billion bushels to a projected 15 billion bushels needed by 2010 will require an additional 12 million acres of corn, Collins notes. One billion of the 2-billion-bushel increase could come from reductions in the feed and export markets, leaving about 6 million acres of additional land needed.

“I doubt that we will take much out of soybean acres, which are currently at 63 million, because of the good soybean prices. Wheat acres have continued to increase with excellent futures prices and not much could come from there.

“There is discussion about taking land out of CRP land and putting a portion into corn. Currently about 37 million acres are in CRP, but USDA/NRCS considers only about 7 million acres suitable for corn production.”

In the long-term, the United States will need much more than that to meet projected production of 32 million gallons of ethanol annually. “If we are to make ethanol from corn grain, we would need 68 million acres, which is 72 percent of the corn grown in the United States. I doubt very seriously that's going to happen.”

An additional 15 billion gallons of ethanol fuel would most likely come from cellulose. Collins pointed to a Department of Energy estimate that 428 million dry tons of residues could be moved into the cellulosic industry from U.S. crop fields.

“That would produce 34 billion gallons of ethanol, when we get the technology developed. But that's not a reality either. Only about 28 percent of the land could have residue removed for cellulosic ethanol production because of concerns over soil erosion. That's only going to give us 8 billion gallons.

“Other cellulosic sources are dedicated crops such as switchgrass, poplars and other perennial crops. The most talked about is switchgrass, a perennial, warm-season grass with both upland and lowland types.

Switchgrass “is not for the grower who is faint of heart because it takes so long to get started,” Collins said. “Expected yields are 8 tons per acre for Alabama, Florida, 4 to 6 tons, Iowa, 6 tons, and Nebraska, 9 tons. In Washington, where we are growing it under irrigation, we are getting yields of 13 tons per acre. We expect that to be 15 tons for the coming year and we're not sure where it's going to max out.

“The DOE study says that 378 million dry tons of switchgrass would require between 38 million and 75 million acres. If we took the low estimated yield of switchgrass and put it on 75 million acres, we hit 30 billion gallons of ethanol, and that pretty much hits the projected supply.”

Finding the acres is a different matter, however. Collins says only about 20 million of 37 million acres currently enrolled in CRP could be available for conversion to cellulosic ethanol from switchgrass, and 17 million of those acres are in five states, including Nebraska and Texas.

Much of the switchgrass production could come from 130 million acres in pastures and alfalfa. “From my point of view, wheat, corn and soybean growers are not going to grow switchgrass. I believe it's going to be the hay growers, the alfalfa growers. They already have the equipment. They're already set up. They know how to collect it and transport it.”

On the other hand, “pastures present a problem because switchgrass profitability is going to be distance dependent. Most of our pastures are small in acreage. So collection is going to be a problem.”

There could be other problems in the short-term as food and ethanol use compete for corn. Collins noted that in 17 of the last 50 years, corn yields were significantly below average. “What impact will losing 30 percent of corn production have on food production and on ethanol? Those are some things we really haven't thought about in the long term. We also have to be concerned about legislation and energy policies.

“And what happens when U.S. exports from corn-based ethanol production declines? Have we lost those markets? Will we be able to get back in? Those are questions we need to think about.”

Currently, there are 2.27 billion acres of land in the United States, 32 percent in forest, 26 percent in grassland and range, 20 percent in cropland, and the rest in swamps, deserts and other public lands. Cropland acres comprise around 458 million acres. Sixty-percent of those acres are in corn, soybeans and wheat.