(a) Unit of certification. The entire acreage standing at the time of inspection must be inspected as a unit from a map showing the exact specifications and permanent location of the field.(b) Isolation.(1) Pasture grasses. Foundation, registered, and certified sprigs must be isolated from any other strain of the same species or other objectionable species by a distance of at least 30 feet.(2) Turfgrass (except St. Augustine grass). Foundation, registered, and certified class stock must be isolated from any other perennial grass by a strip at least 10 feet wide. In addition to the required 10 feet of isolation, when the contaminant is a Cynodon spp. producing viable seed, the production field must be isolated by a terrace or a similar barrier approved by the inspector so as to prevent washing of the seed into the production blocks. This barrier will be included in the 10-foot isolation distance.(3) St. Augustinegrass. Foundation, registered, and certified class stock must be isolated from any other perennial grass and/or objectionable weeds by a strip at least six feet wide.(c) Specific requirements. Reference should be made to the following table.