Miami-Dade and Broward property appraisers say they have no choice: Year after year, they give up millions of dollars to developers who seek property tax breaks meant to help farmers.

State law requires them to grant tax breaks on land used for "good-faith commercial agriculture" but isn't clear about what that means. Developer-friendly court rulings have further slackened the rules, allowing corporate interests to seek farm subsidies even as they plan to bulldoze pastures and cornfields.

But even the law's loose guidelines haven't been consistently enforced. Appraisers in both counties have shied away from challenging suspect farms, forfeiting revenue that could go to public safety, roads and schools.

"Every one of these stinks to high heaven, " said Ronald Schultz, a retired appraiser with 29 years of experience in two Florida counties who examined tax records and visited properties with The Herald. "On a personal level, it offends me."

In Miami-Dade County, the appraiser's office has signed off on hefty tax breaks without requiring firm proof of genuine commercial farming. Among The Herald's findings:* The appraiser's office has granted farm subsidies despite incomplete or late applications, zoning that prohibits agriculture, and cursory inspections.

"Just because we don't see the cows doesn't mean they're not there, " said Miami-Dade appraisal supervisor Steven Davies.

• The office has made costly mistakes. Officials acknowledged granting more than $35,000 in tax breaks to a Miami Gardens developer without seeing an application. Warehouse builder Harry Dornbusch's 2004 ad valorem property tax bill on 7 1/2 acres: $180.20.

  The appraiser's office also erred when it gave an extra $40,000 in savings to Lancaster Homes last year, exempting more acres from full taxes than the developer had requested.

  "I think we just flat out blew this one, " said Miami-Dade Property Appraiser Frank Jacobs. "We should have just granted what they asked for."

• When the county does deny the tax break, and landowners appeal, the office has failed to aggressively defend some of its decisions.

  County officials have been sent to battle developers' lawyers at formal hearings without legal counsel of their own. In at least one case, county inspectors missed a hearing where their testimony was essential.

• The law says appraisers can scrutinize leases between landowners and farmers for evidence of a good-faith agricultural business. But the Miami-Dade office has accepted the word of developers and ranchers who said they reached handshake agreements allowing free use of the land.

"If I had a verbal lease, I'd be shaking like a leaf about my proof, " said Dave Bruns, a spokesman for the Florida Department of Revenue, which oversees tax collection but does not decide individual cases.

Schultz said he always required written leases. "You have to provide me with evidence, " he said. "When you don't have a lease, you could have the same cows being used in five different places."

Jacobs, who served as deputy appraiser before he was appointed to the top post in July, said his office is doing its best to sort out the real farms from the tax dodges. The office has limited resources, and he has to pick his battles.

"The advice that we're getting is it's a virtual impossibility to win, " Jacobs said.

Even Schultz, who aggressively challenged corporations seeking farm subsidies, emphasized the law's weaknesses and a political climate that favors developers.