Potato seed is usually produced in regions that are isolated from commercial potato production, with the intent of preventing disease contamination by insects, animals, or human traffic. Certification of potato seed in the United States has been refined significantly during the twentieth century. The certification results provide the buyer with a guide to the quality of the seed produced by seed growers in each state. Proper cutting of potato seed tubers is important if maximum productivity of the seed lot is to be realized. The primary outcomes desired of a good seed cutting operation are uniform-sized seed and minimum spread of disease. Potato planters consist of three basic designs; the cup planter, the pick planter, and the assist-feed planter. Pest control in seed potato fields is essential to the success of the industry. Insect pests such as the green peach aphid must be controlled to prevent disease in succeeding plantings.