Cover crop of barley

Cover crop of barley (2008 Glenn Fawcett/Baltimore Sun)

Maryland farmers planted a record acreage in pollution-absorbing "cover crops" this past fall, state officials announced today, hailing it as a new milestone in the Chesapeake Bay restoration effort.

With the state paying them to do so, farmers seeded a total of 429,818 acres statewide in wheat, barley and other crops before winter set in, in what scientists say is one of the most cost-effective ways to curb nutrient pollution fouling the bay. 

The plant nutrients in fertilizer - phosphorus and nitrogen - are prone to wash off or soak into ground water if left in the soil after the fall harvest, contributing to the formation of the bay's "dead zone" every summer, where fish and crabs can't get enough dissolved oxygen to breathe.

By planting grain crops in the fall and then not fertilizing them, at least until growing resumes in the spring, farmers can control the amount of nitrogen and phosphorus washing off their fields into nearby streams and ultimately the bay.  Officials estimate that 430,000 acres planted will keep nearly 2.6 million pounds of nitrogen out of the bay, which is 60 percent of the nitrogen reduction the state needs to make in the next two years.  The plantings also prevent an estimated 86,000 pounds of phosphorus from getting into the water. 

Officials say this winter's cover crops are the most ever, and that the acreage planted exceeds the state's goal for 2013 by 21 percent. (That record comes with an asterisk, though - state officials originally set a target of planting 460,000 acres by 2011, but scaled that back in 2010 when the plantings weren't meeting projections.)

Gov.Martin O'Malley issued a statement calling cover crops "the workhorse of our Bay restoration efforts" and thanking participating farmers.