The farm bill approved by the Senate last week makes significant changes in existing farm programs, some for the better. But it takes a disproportionate whack from environmental programs, needlessly trims food stamps and does not fundamentally alter the program’s bias toward relatively well-off growers of big crops like corn, wheat and soybeans.

The bill would cost $969 billion over 10 years, about $23 billion less than projected. Much of this comes from eliminating notorious subsidies like the direct payment program, which doled out $5 billion a year to farmers in good times and bad.

The Senate put some of that savings into a suite of generous crop insurance programs that will protect farmers against both natural disaster and market fluctuations. These programs will disproportionately benefit large farmers (the more you grow, the bigger the subsidy) who could afford to pay a bigger share of the premiums. An exasperated Senator John McCain said he was “hard-pressed to think of any other industry that operates with less risk at the expense of the American taxpayer.”

Despite the efforts of Senator Kirsten Gillibrand of New York to keep food stamp programs intact, they were cut by $4.5 billion over 10 years — a fraction of some $750 billion in total spending but harmful to many poor families. Conservation programs that encourage farmers to withdraw highly erodible land from production were slashed by 10 percent. These cuts would have been less painful if the Senate had spent less on crop insurance.