Karelian curly birch (Betula pendula var. carelica) comes from the border region between Russia and Eastern Finland and is highly valued there. It is the classic wood for finest furniture, arts and crafts items as well as especially for knife handles of Nordic knifemakers. The wood is fine-pored, hard and dense, significantly heavier than normal birch wood. However, the occurrence is very limited, usually only very isolated burl logs are found among hundreds of normal birch trees. Burl formation is genetically determined, soil conditions and site conditions probably also have an effect. The trunks are rarely longer than 1.50 m, even diameters of 25 cm are already among the great exceptions, mostly the trunks are 20-25 cm thick. The wood is so rare and valuable that it is traded by weight per kilo in the growing areas.
