The source refers to the genetic origin of the seed being inspected for certification. Certification does not place parameters on the source. The applicant defines the source, for example, a geographic region spanning several counties or one locality within one county. Several requirements must be adhered to for production fields, a number of which pertain to process and documentation. The two of interest from a genetic basis are isolation and land use.
Isolation refers to the spacing between fields of plants from different genetic origin.
The isolation distance for grasses is 165 feet and forbs is 1320 feet. For self-pollinating species no distance is specified. The minimum rotation time period is three years. This means that three years must pass before a different seed source of the same species can be planted on the same field. Certification is a means of providing information to customers.