I cut these Elms this evening and can't stand not knowing exactly which sub-species it is.
 I know from the corky wings that it's either "winged" or "rock" elm...but I can't figure out which is which 

 This first set of pictures is from a scrubby little tree I cut in the edge of a field (if that matters)  
 Both trees look a lot alike, but there is some subtle differences and I just can't lay a finger on it.
 I've read that Elm varies greatly from tree to tree, so who knows...it may be the same stuff.
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