Wax looking, and now I will know the smell. Thank you both, it matches your description. I will avoid it in the future now that I know, not worth the trouble as I split by axe.
Splitting elm by axe can be challenging, heck sometimes it is challenging splitting it with a hydraulic splitter. Good BTU firewood so you will be rewarded for your efforts.
It has a similar grain as sweetgum; something else that can be hard to split by hand. Even with the splitter I often have to use the axe to cut apart some splits.
Eh, hydro's make even elm easy to split. I did a couple cords this winter. My splitter is way less that 20 tons. Maybe 15 or so. One advantage to horizontal splitting at least one like mine that has the wedge on the end and pusher on the cylinder, is that you just put the next round in if there's strings holding the splits together. It simply just breaks the stringiness apart. A vertical splitter, with the wedge on the cylinder can't do it that way. I don't believe so at least. Not from what I recall at least Ashwatcher will get a kick out of this.
Horkn I made a backer for my splitter that allows splitting of any stringy wood by holding the wood away from the foot plate and providing the blade of the wedge to go all the way thru the wood. I have since had the backer welded and that works better. I split most of my wood in the horizontal plane.