The timber scribe is used to mark trees to be felled by cutting a strip of bark, also to indicate - when unloading a ship - the number of beams of a raft (1).
The timber scribe has a metal blade with a U-shaped end and a wooden or horn handle of 10-15 cm. One side of the U is sharp (cf. clog maker's scribe, beam scribe, rubber tapping knife).
Some timber scribes have a foldable blade and some sort of plate to protect the hand.
See also the hoof cleaning knife. [MOT]
(1) JANSEN: 117.