ANNAPOLIS, Md. (AP) — Maryland Gov. Martin O'Malley is asking federal officials for drought aid for 13 of the state's 23 counties.

The governor announced Wednesday that he had written to Agriculture Secretary Tom Vilsack seeking a disaster designation for the counties on the Eastern Shore and in central and southern Maryland. The state estimates farmers in the counties have lost between 30 and 54 percent of their crops.

The request covers Dorchester, Somerset, Calvert, Kent, Talbot, Caroline, Wicomico, Cecil, and Queen Anne's counties on the Eastern Shore. Anne Arundel, Charles, Calvert and Prince George's counties are also included. State officials say rainfall has been 70 percent of normal since the end of January.

State agriculture officials, meanwhile, says they're offering free grain testing for toxins present during drought that are poisonous to livestock.