WASHINGTON -- The chairmen of the Senate and the House Agriculture Committees unveiled drastically different plans for funding farm conservation programs last week, setting the stage for a debate that may last well into September with billions of subsidy dollars for farmers at stake.

A central element of the discussion is the Conservation Security Program, or CSP -- a 5-year-old program that Senate Agriculture Committee Chairman Sen. Tom Harkin of Iowa wants to boost but his counterpart in the House wants to freeze. It expanded conservation by offering subsidies to working farmlands that adopted new environmentally friendly techniques rather than only providing money to farmland taken out of production.

But it was undermined at its inception because of budget constraints -- a problem that will play into determining its future.

House Agriculture Committee Chairman Sen. Collin C. Peterson, D-Minn., cut $1.1 billion from the CSP and froze enrollment until 2012 in draft legislation announced May 17.

Harkin responded: "If you don't have any sign-ups for five years, you basically kill the program."

He created the program in 2002 to provide economic incentives for conservation-oriented farming practices and included $2 billion a year in funding. But the money didn't get allocated for two years and then was cut $41 million in 2004, $202 million in 2005 and $259 million in 2006 -- a move that Harkin and CSP proponents say severely limited the program's effectiveness.

Federal subsidies to Iowa farmers totaled $5.3 billion in the first four years of the 2002 farm bill, according to data from the Environmental Working Group, a government watchdog group. Of that, $4.2 billion went to commodity crops.

Comparatively, conservation measures in Iowa were subsidized at about $883 million from 2002 to 2005, placing the state at the top of conservation subsidy recipients with an average of more than 10 percent of the annual federal spending.

"Our members are very focused on being good stewards of the land," Iowa Farm Bureau Federation National Policy Advisor Mark Salvador said Friday. "The unfortunate circumstance around the '02 CSP program all pertains to funding."

In addition to the money they provide farmers, conservation programs are critical to protecting the environment, according to Michelle Perez, senior agriculture analyst at the Environmental Working Group. And retired and working lands are equally important to target, she said.

"You really have to have both approaches working," Perez said. "All of the programs . each have their own specialty that appeals to a different set of farmers and a different set of landowners, and maximizes environmental benefits."

Harkin is expected to unveil a measure in June to combine working-land conservation programs under one umbrella, the Comprehensive Stewardship Incentives Program, or CSIP, bundling CSP with the Environmental Quality Incentives Program and the Wildlife Habitat Incentives Program.

Harkin will propose expanding conservation funding by an additional $6 billion, a 26.5 percent increase to the current baseline of $22.6 billion over five years. The money would come from a $20 billion reserve fund Congress approved for the farm bill reauthorization and would provide CSIP with $3 billion, $2 billion of which would be designated for CSP.

But Harkin's counterparts in the House are steering clear of the reserve fund, instead proposing to fund some conservation programs by cutting others. Peterson last week instructed subcommittee members to avoid dipping into the reserve fund.

The Environmental Working Group's Perez said adequate funding would require doubling conservation spending to $6 billion a year.

Contact Emre Peker at Medill News Service at emailemre@gmail.com.