Translations:Manfred Klett: Von der Agrartechnologie zur Landbaukunst/1378/en

When one turns one's gaze to bark-forming trees such as the oak, one can say to oneself: the outer bark is the expression of an earth-near flowering process that outlasts the seasons — which, simultaneously with the inner bark, the cambium, the sapwood and heartwood, lends the tree its durability through the changing of the year. Seen thus, the source material for the oak bark preparation is likewise a materiality that has arisen from a blossom-like process. This confirms Rudolf Steiner's answer to a listener's question: "Does the whole bark come into consideration?" "Really only the outer layer of bark, which crumbles away when one detaches it."