that looks like oak to me. i'm gonna say white oak. the easiest way to tell black oak is by the lil orange lines in between the bark ribs. also black oak has a much less of a flaky bark. black oak is in the red oak family and the barks are similar. In my experience cottonwood never splits that easy. all the cottonwood i've split, splits like elm, very stringy, and the wood is white in color. plus the bark is much more dark brown and less red than your pics.
all the poplar around here is white when you cut it then the wood turns black after its seasoned for a few months. then after a year it turns a dark brown.
oak burns good after a year of seasoning, but it burns better after 2-3 years of seasoning. which explains why it needs extra air to burn it.
what part of the country are you located in?