(1)  Rootstocks. All stone and pome fruit nursery stocky being grown for Blue Tag Certification shall be on rootstocks from registered trees except for stone fruit trees grown on peach seedlings and pome fruit trees grown on apple and pear seedlings. These seedling rootstocks, when grown from commercial seed, will be acceptable if seed transmissible virus content does not exceed five percent. Clonal rootstocks used in the production of Montana Certified Blue Tag Nursery Stock must originate from Registered Stool-beds.

(2)  Location. Nursery stock being grown for certification shall be planted sufficiently apart to maintain its identity and shall he kept clean cultivated. It shall be designated as to rootstock, top-stock, and interstock sources. There shall be no rebudding or regrafting of nursery row stock unless such stock is reworked with scions from the original registered scion-tree.

(3)  Seed. Certified seed shall have been produced on Registered Seed Trees or commercial seed having been tested and found to have a transmissible virus content that does not exceed five percent.

(4)  Tagging. A Blue Tag shall designate trees produced from Registered Scion-source trees and which have been propagated on rootstocks produced from Registered Seed-source or Stool-bedtrees; or which are self-rooted.

All nursery stock meeting the requirements of this program when sold shall have the variety, interstock and rootstock designated where applicable as follows: Variety/interstock/rootstock.