1) Larch
2) Birch
after that it does not matter..

I've got acres of the stuff on my place and I found if it is cut live and left without being cut up it will rot long before it dries. Personally I think it is best to split right away (and that is a bugger when it is wet). Luckily I have LOTS of dead standing with the bark off, that stuff burns incredibly hot and splits like a dream.

If it is just for heat
 

I like to use soft coal, that is the kind Alberta has 1/2 the world's supply, it is nice and warm, burns for a couple of day between fills, and you can use the clinkers on your drive way. In the old days when some of the mines in Drum were still operating a farmer could get a grain truck full for $10.

I'm sure it costs more now, but if you are busy or lazy and I'm both coal was my solution.

On the coast they burn a lot of Alder.

One an elk trip one year I met a local in Creston. He asked me about firewood prices on the coast. When I told him a lot of people burned Alder, he came unglued. He looked at me like I had married my cousin. He said Alder is just a dang weed. He also said he would put on a sweater before he ever put a stick of alder on his fire.:angry3:

he burned Tamarack.

Where can it be bought now?