In all, a record 1,767 farmers have signed acreage up for the coming winter, including 206 who are enrolled for the first time, according to the state Department of Agriculture.
The program's success has exceeded by 55 percent the goals set by the Phase I Watershed Implementation Plan.
Gov. Martin O'Malley sees cover crops as one of the most cost-effective strategies for protecting the Chesapeake from unwanted nutrient loading.
On Tuesday the governor hailed participating farmers for working to "diversify their farming operations and use new and innovative ways to protect the Chesapeake Bay. Together, we are … securing the future of Maryland agriculture and our environment for generations to come."
Farmers are paid $53 an acre to plant winter cover, or less if they plan to harvest the crop. The state has appropriated $18.2 million for the program this year, up from $8 million in 2008 as participation has grown, said department spokeswoman Julie Oberg. The money comes from state "flush taxes" and the general fund.
Typically, 25 percent of the acreage initially enrolled ultimately is not planted, for a variety of reasons, such as bad weather, she said. State inspectors will verify the planted acreage in the fall and winter before the checks are written.
Once the cover crops — mostly rye, barley and wheat — emerge, they hold soil in place and take up excess nutrients left behind by the summer crops. Farmers also agree not to fertilize the soil until after March 1. The winter crops are killed or tilled to enrich the soil for the next growing season. Less than a third of the grain is harvested, Hance said.
Allegany County, in Western Maryland, had the highest percentage of its eligible farmland enrolled, at 88 percent. Queen Anne's County, on the Eastern Shore, had the largest number of acres enrolled, at 63,838.
Hance said it's too soon to say whether the bay's health has improved in response to the growth of the cover crop program.
"We understand sometimes it can take 20 or 30 years before we'll see an impact on water quality," he said. "We operate on the assumption these practices have been research-driven … We will see a water quality benefit. But it's not an immediate benefit."
Maryland weather blog: Frank Roylance on meteorology
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