Berkano is the eighteenth rune of the Elder Futhark, second in the third aett, carrying the phoneme "b." Its reconstructed name means the birch, or a birch twig or poplar. The rune poems describe the birch as bearing no fruit yet putting out shoots and shining leaves, an image of growth, renewal and greenery. The birch is widely linked with birth, nurture and the feminine, associations later drawn out in the rune.
Berkano stands second in the aett of Tyr. Its Old English futhorc counterpart, beorc, meaning birch, receives a stanza in the Old English Rune Poem describing the birch as fruitless yet bearing shoots without seed, beautiful in its branches, high and fair-crowned, adorned with leaves, touching the sky. Berkano survived into the Younger Futhark as bjarkan, and appears in both the Norwegian and Icelandic Rune Poems, the latter associating it with a leafy branch and a young tree, a green mountain.
Runologists reconstruct the Proto-Germanic form behind the name as *berkanan, part of the comparative linguistic evidence, alongside cognate vocabulary across the older Germanic languages, used to establish the name's original sense independent of the later rune poems themselves.