WASHINGTON — Expressing the view that up to 50% of acreage set aside under the Conservation Reserve Program is not environmentally sensitive, the American Bakers Association is advocating the release of millions of acres from the program.

Comments from the A.B.A. were sent to Secretary of Agriculture Tom Vilsack in an Oct. 19 letter from Robb MacKie, president and chief executive officer.

Releasing acreage from the C.R.P. "will give farmers the latitude they need to respond in times of low supply or high demand," Mr. MacKie said.

The baking industry has been advocating the release for several years, a call that grew particularly loud in 2008 when grain prices reached record highs. Wheat acreage has been entered into C.R.P. at a disproportionately high level, exacerbating a secular shift in U.S. crop acreage away from wheat in favor of other crops.

The A.B.A. has focused its lobbying efforts on the initiation of an Environmental Impact Statement, a prerequisite for changes in the C.R.P. to test whether some C.R.P. acreage is not environmentally sensitive and suitable for release from the program.

Cory Martin, A.B.A. senior manager of government relations, said the U.S.D.A. has begun to demonstrate a willingness to proceed with the E.I.S.

"A.B.A. has been calling on U.S.D.A. to begin the E.I.S. for almost two years now," Mr. Martin said. "Once the E.I.S. is complete, the U.S.D.A. will have the information necessary to release viable acreage from the program, something that will benefit farmers, bakers and most importantly, consumers."

In its letter to Mr. Vilsack, the A.B.A. conceded that releasing acreage in 2008 would not have avoided the run up in commodity and food prices.

"Releasing non-environmentally sensitive lands from the C.R.P. will help to deter similar crises from occurring in the future," Mr. MacKie said. "With more non-traditional influences on commodities markets today, like demand for corn-based ethanol and the inflationary impact of index fund activity, opening viable C.R.P. lands will ensure that farmers can react appropriately to increasing worldwide demand for basic food commodities."

Mr. MacKie reminded Mr. Vilsack that the C.R.P. was never intended to serve as a permanent land-retirement program but rather as a "short-term supply control mechanism."

"A.B.A. recognizes the need to protect environmentally sensitive land, such as land with a credibility index equal to or greater than eight," he said. "As such, A.B.A. strongly encourages U.S.DA. to ensure that highly erodible acreage be kept under contract while loosening production restrictions s on lands not deemed environmentally sensitive. A.B.A. also urges U.S.D.A. to institute policies, such as penalty-free early outs from contract provisions, that allow program acreage to be more easily accessible in times of supply shortage and high market demand."