Term asturleones with many phonetic variants depending on the area : belortu , bolorto , bolortu , bilurtu , bilorto , bilingual . . . Twisted flexible branch is useful for tying and it can be vine, retama, hazel, ash or wild vines and climbers such as vital clematis or beggar grass. The term is also used in Cantabria and Galicia and sometimes appears written with V. It might have Celtic origin at Corominas' suggestion.