One thing holds consistent across the numerous worlds of science fiction and fantasy: everyone speaks the same language. Whether it's Lojban, English, Common, or the High Tongue of the Autumn Empire; there's one language that everyone knows, unless plot demands otherwise.
Do not gather and heap up and store for yourselves treasures on earth, where moth and rust and worm consume and destroy, and where thieves break through and steal. Matthew 6:19 KJV
Dustwood is technically not a wood from a specific tree. It is an created fuel for fires.
Starting with the sawdust from a sawmill, adding a mixture of wax or pitch, and a few other things, the mixture is pounded or pressed toghether tightly. It is normally smashed into a round container, so when it is slipped out, it looks like a small perfectly round "log". (actually a lathed log, but you get the idea). It can either be used as a log or slices of a log can be used for a fire.