Generally,hornbeam (Carpinus betulus),and beech (Fagus silvatica) are considered for the best fire wood in Croatia.Birch(Betula pendula; B. verrucosa,..) is great for kindling,for it takes flame readily.I also use ash(Fraxinus angustifolia L.).Black locust(Robinia pseudoacacia) burns well,but fiercely,with lot of sparks,and oak(Quercus robur) is used for firewood,but mixed with hornbeam or beech,because it smoldering.Therefore oak is 1/3 cheaper than hornbeam and beech.