Woods are wild places, waste and desolate, that
many trees grow in without fruit, and also few having fruit. In
these woods there are often wild beasts and fowl; herbs, grass,
leas and pastures grow here and medicinal herbs are found in woods.
In summer woods are beautied with boughs and branches, with herbs
and grass. But woods are also places of deceit and hunting, for
wild beasts are hunted here, and watches and deceits are ordained
and set of hounds and hunters. They are also places of hiding and
lurking, for often thieves hide here and lay wait for men to pass,
whom they rob and often kill. And so for many various ways strangers
often take a wrong turn and find themselves on the wrong path, and
come to places where thieves hide out, and not without peril. Therefore
knots are often made on trees and bushes, in boughs and in branches
of trees, in token and mark of the highway, to show the certain
and sure way to travellers; but thieves often turn and change these
knots to mislead them, and lead them off the right path by false
tokens and signs.
[Cited in Medieval Lore, ed. R. Steele
(London, 1893), pp. 91-92 ]