(1) A registration number approved by the department will be assigned to each registered scion tree.

(2) Only registered trees are permitted in a registered scion-block.

(3) Registered Prunus trees shall be located at least 100 feet from any nonregistered Prunus tree. Chaenomeles, Cydonia, Crataegus, Malus, Pyrus, and Sorbus trees must be located at least 60 feet from any nonregistered plant of the Rosaceae family, and known or potential host plants in the field, under protected cultivation, or in the wild. The ground in a scion-block and for a distance of 20 feet surrounding it shall be kept either clean cultivated or in an approved, properly controlled ground cover. Registered scion-block trees shall be planted and maintained in a manner and at sufficient distance that branches of different varieties do not overlap. Care shall be taken in the use of pollinating insects and pollen application to prevent the transmission and spread of virus diseases through the use of infected pollen and/or its application. Registered scion-block trees shall not be used for propagation purposes until trueness-to-name has been established. Each tree shall bear a permanent registration number.

(4) The rootstock and top-stock sources of the scion-block trees shall have originated from Generation 3 trees established under this program or from virus-tested trees originating through the Inter-regional Project No. 2 (IR-2), now known as National Research Support Project-5 (NRSP-5) or other departmentally approved virus-tested sources. If the tree is scion-rooted, its source shall have met the above requirements.