Farms in five Massachusetts counties have been granted federal disaster relief for production losses suffered because of unseasonably cold weather last spring. The Department of Agriculture declared Berkshire, Franklin, Hampden, and Hampshire counties primary natural disaster areas. That means that farms that meet certain requirements are eligible for loans and other assistance from the Farm Services Agency. Farms in Worcester County, which was declared a contiguous disaster area, are also eligible for loan assistance. Crops damaged by unseasonably late frost and freezes between April 28 and May 17 included asparagus, strawberries, blueberries, and cherries. Farmers predicted production decreases of at least 30 percent.