Berkanan
The Tree Without Seed
Renewal that needs nothing from outside: the tree regrows from its own root, and bears no fruit at all.
The reconstructed *berkanan is attested later as Old English beorc, Old Norse bjarkan and Gothic bercna. The Old English poem describes a tree that bears no fruit and yet sends up shoots without seed, its branches lovely, its high crown reaching towards the sky. Scholars have long noted that propagating from suckers rather than from seed suits the poplar better than it suits the birch, and the mismatch is unresolved. The Norwegian poem calls it the greenest-leaved of shrubs before pairing that with an unrelated half-line about Loki prospering by deceit, a rhyme habit that poem keeps throughout. Readings of this rune as birth or motherhood are twentieth century.
Light
Renewal that needs nothing from outside. The tree of the poem regenerates from its own root, and all three glosses value it for leaf, shoot and green growth rather than for yield.
Shadow
It also bears nothing. A tree praised for its foliage produces no fruit, and the Norwegian poem sets that greenness immediately beside a line about a successful deception.