The Thracian word berza(s)
Word berza(s)
Meaning birch
See also Proto-Indo-European: *bʰerhₓĝos ‘birch’

Other words that might be of interest
ida ‘tree, forest’, muka ‘seed, clan, posterity’, pupa ‘beans’, pura ‘maize’, pusinas ‘spruce forest, pine forest’, skapt- ‘to dig’, briza ‘spelt, rye’, zilai ‘wine’