That portion of a plant, such as a corn stalk, left in the field after harvest. Crop residues are measured for farmers who use conservation tillage to implement their conservation plans to meet conservation compliance requirements. These farmers are required to maintain a minimum level of crop residue to be in compliance. Under revisions to the conservation compliance program in the FAIR Act of 1996, farmers are allowed to use third parties, certified by USDA, to measure levels of crop residue.