State Seed Department potato inspectors inspect fields in the state a minimum of three times during the pre-harvest period. Inspectors perform the first inspection approximately 45 days after planting and the second approximately 10 days later for the purpose of determining virus levels, presence of disease, varietal purity and other factors associated with seed quality. A third inspection is performed prior to vine-kill primarily for the purpose of bacterial ring rot detection.

Some varieties, especially those known as potentially symptomless or that show very mild symptoms, are subjected to laboratory testing for the presence of mosaic viruses. Also, growers may choose to have any seed lot summer tested for virus X and other pathogens. North Dakota seed standards are published in Administrative Code.

Growers are responsible for maintaining the quality, health and condition of seed fields in the program. Among the most important factors:
  

• Insect control must be maintained early and until vines are killed. Excessive insect injury can lead to disqualification of seed lots.
• Vine killing may only commence with prior approval of seed inspectors.
• Factors such as excess weeds, hail, chemical damage that interfere with the inspector’s ability to determine field condition lead to disqualification.
• Growers are encouraged to rogue early and often, in an effort to lower total serious viruses and avoid the spread of such.
• Fields are reinspected at the discretion of the Department, if requested within three days of rejection and provided no additional roguing has occurred.