Field standards

Factor Open Pollinated Varieties A, B, or R Hybrid Production Seed Parent Pollen Parent Pollen shedding female plants (Maximum) 1:1,000* 5:1,000 Branched wild-types 1:1,000 1:1,000 1:1,000 Purple plants ** 1:1,000 1:1,000 1:1,000 White seeded plants 1:1,000 1:1,000 1:1,000 Total including above (maximum) 5:1,000 4:1,000 4:1,000 4:1,000 Isolation (minimum) ** 5,280 feet 5,280 feet 5,280 feet 5,280 feet Corn plants bearing seed none none none none *Standard applies only to A-line. **Must be isolated from other varieties, strains, hybrids, volunteer sunflower, noncertified crops of the same variety, and hybrid and wild Helianthus species.