I have a ton of these growing around the house. This one appears to be dying but there's 4-5 more growing on this hill that need to be cleared. If I can smoke with them I'll be good for years.
Yeah, definitely not an American elm - the leaves are too short.
I think these are simple, not compound. (Look for buds at the base of the leaf.)
Could be cedar elm?
Ash family ?
Did you click on the 2 links I provided ??
IMHO it is some type of ash, the leaves and bark look good for ash and in your third photo I can see the seed cases hanging among the leaves that are similar to what ash trees produce.
Might be this one, it is found in Mississippi-
http://dendro.cnre.vt.edu/dendrology/syllabus/factsheet.cfm?ID=475