This unfurled ‘page’ of lettering on a Beech tree literally means a book…
The German word for “letter” – Buchstabe – literally means “Beech stick” and refers to a time when an old form of lettering called runes was carved or punched into staves or sticks (Staben) made of beech wood (Buche) [Fagus sylvatica]. Our word stab comes from this pointed stick, too.
Runes were used for divination and when making important decisions. The German / Old Teutonic was itself derived from Old Norsk bók meaning beech. So, the beech tree is the origin of the English word book. In Old English it was bóc.
Buchstaben, then, literally means beech graffiti. And, lots of letters put together … a book / Buch / and back to beech. Love it!
The smooth bark is an ideal surface for carving. As the tree grows in height and girth, the letters rise up the trunk and expand, giving clues to the tree’s age.
Extracts from the Oxford English dictionary (2nd edition 1989)
A com. Teut. Word
These forms indicate an OTeut. *bôk
The original meaning was evidently ‘writing-tablet, leaf, or sheet’
OE. bóc charter: in pl. tablets, written sheets, hence ‘book,’ a sense subseq. extended to the singular.
Gothic does not show *bôks, but an apparently derivative form bôka strong fem., in sense of ‘letter’ of the alphabet, pl. bôkôs litteræ, γράµµατα, writing, document, book.
The OED adds a note to dampen this lovely eponymous circularity of meaning:
[Generally thought to be etymologically connected with the name of the beech-tree, OE. bóc, béce, ON. bók:—(see beech), the suggestion being that inscriptions were first made on beechen tablets, or cut in the bark of beech trees; but there are great difficulties in reconciling the early forms of the two words, seeing that bôk-s ‘writing-tablet’ is the most primitive of all.]
Never let truth get in the way of a good story, though.