The heart wood doesn't look green enough for poplar.
Around here, a month ago the power company sent crews around to cut down every [dead] ash tree that threatened power lines.
We have ash laying on the shoulder of the roads all over the place and people are scrounging it up for firewood.
Did you find this wood under a power line?
No I don't believe so. I guess I just assumed ash was a heavier. I'm thinking you where right the first time with basswood. The splits are pretty light I can only imagine when they are dry. From a little research looks like it Ash but I've never cut into either. From what I've read is ash dosent much mositure so how does the weight compare with other species while green