The United States Department of Agriculture eased some organic certification requirements for Marin and 52 other California counties earlier this month at the request of two organic certifiers in the state. 

It’s the second exception in two years; Marin producers also got a reprieve back in 2012. 

The so-called variance, approved on Feb. 12, affects foraging requirements for cows and other ruminants on local pastures for the 2014 grazing season.

The drought has burned through the coffers of many ranches and dairies that have been forced to buy increasingly scarce and expensive organic hay. Straus Family Creamery, which purchases milk from eight dairies in Marin and Sonoma, is considering increasing prices to cope with rising costs, according to founder Albert Straus.

“We need the farms to stay viable and healthy,” he said.

The lack of rain is particularly problematic for organic operations, which must let their animals forage a set number of days in the year—a difficult proposition when grasses fail to grow.

The variance exempts ranchers from grazing requirements in February and March, which represent about half of the 120 days typically required for foraging. The U.S.D.A will reassess the variance as the year continues, leaving open the possibility of a longer exemption.

Stacy Carlsen, the county’s agricultural commissioner, said that he expects it will be necessary. 

“They recognized that they’ll give us a window because there’s no grass now, but the way I look at it, there is sort of a two-month window when grass should be growing the most, and currently it’s not growing at all,” Mr. Carlsen said.