Article 4
1. Member States shall provide that only approved basic material is used for the production of forest reproductive material which is to be marketed. 2. Basic material may only be approved by: (a) the official bodies if it meets the requirements set out in Annexes II, III, IV or V hereto, as appropriate; (b) reference to a unit known as "the unit of approval". Each unit of approval shall be identified by a unique register reference. 3. Member States shall provide that: (a) approval shall be withdrawn if the requirements of this Directive are no longer met; (b) after approval, the basic material for the production of reproductive material under the selected, qualified and tested categories shall be re-inspected at regular intervals. 4. In the interest of conserving plant genetic resources used in forestry as specified in specific conditions which shall be established in accordance with the procedure laid down in Article 26(3) to take account of developments in relation to the conservation in situ and the sustainable use of plant genetic resources through growing and marketing of forestry reproductive material of origin which are naturally adapted to the local and regional conditions and threatened by genetic erosion, the Member States may depart from the requirements as laid down in paragraph 2 and Annexes II, III, IV and V insofar as specific conditions are established in accordance with the procedure referred to in Article 26(3). 5. Member States may approve, for a maximum period of ten years, in all or part of their territory, basic material for the production of tested reproductive material where, from the provisional results of the genetic evaluation or comparative tests referred to in Annex V, it can be assumed that the basic material will, when tests have been completed, satisfy the requirements for approval under this Directive.