Herb
The victor's leaf — sharp, glossy, and long in the habit of crowning people.
These are associations the community holds, not settled fact — the more a reading is shared, the bolder it sits.
Laurel is the tree of Apollo, and the reason is a story of refusal: Daphne, pursued, becomes the tree rather than be caught. Whatever one makes of that, the leaf ended up on the heads of poets, athletes and emperors, and the word survives in baccalaureate and in poet laureate. The oracle at Delphi was associated with laurel too, chewed or burnt by the Pythia — a detail ancient writers repeat and modern scholars argue about at length.
Craft use follows the classical thread. Bay is written on and burnt for wishes, tucked into cupboards for protection, and slipped under a pillow for prophetic dreams — that last one appearing in English chapbooks by the eighteenth century and never really going away. It is one of very few kitchen ingredients with an unbroken line back to a working oracle.
The leaves are tough and leathery and keep their aroma for a year or more, which is part of why they travelled so well. Nothing about them has been shown to make anyone see the future, but a dried bay leaf held to the nose is a surprisingly strong argument for why people kept trying.
Readings practitioners have offered, ordered by how many recognise them. Take what serves, leave the rest.
Carried forward
Nicholas Culpeper, The Complete Herbal (1653)
Culpeper gives the bay to the Sun under Leo, and then goes further than most: he says that neither witch nor devil, thunder nor lightning will hurt a man where a bay tree is. He offers no evidence whatever, and states it as settled.
Carried forward
Classical Mediterranean practice
Greek and Roman writers connect laurel to Apollo and to the Delphic oracle, where the priestess is variously described as chewing or burning the leaves. Ancient sources say it plainly; what actually happened at Delphi is still argued over.
Credit what you carry. Much of this comes from living traditions, and some of it from traditions that are closed — held by particular peoples and not offered for general use. Where you know whose practice a reading came from, name them; where you don't, say that too.