Being a planted tree in a commercial landscape it's almost certainly a cultivar, perhaps 'Augustine' (which is susceptible to DED). Not sure if there are any growers still producing it. Augustine was planted on the National Mall (and elsewhere in DC) in the 1960's. There still may be a few of those trees left.

Not here. No cultivars are ever grown or sold of this species in our region.. To do well in our climate, the Florida subspecies is grown - from seed. The other trees in the planting are clearly seedlings with varying form and defoliation date (one in background still has some leaves). I'm almost 100% certain this would be a seedling.

sad to see that tree.. that close to the building ...

ken

I wasn't aware that there was a distinct subspecies of American elm in FL. Learned something new. The subspecies is still apparently susceptible to DED, according to the link below. Interesting that you don't see DED much there.

http://hort.ifas.ufl.edu/woody/Pages/ulmameflo/ulmameflo.shtml

Interestingly, there is NO DED here. It has never been reported in the state of Florida (and its also missing from much of the lower coastal plain). Oak wilt has also never been found here - despite many false reports and people have looked.

We have four species of elm common in MidTenn, American, red, winged, and September. Occasionally one will turn yellow and die, but that is not all that common. I'm not sure it is DED or one of the other maladies that afflict elms. I have planted lots of winged elms on my place, and I encourage volunteers. I like them although most consider them trash trees. I am also allowing red/Americans to volunteer. I don't know which I have, I haven't keyed them out. I once read that DED is less of a problem in warm climates, I don't have a source. Oak wilt is present here and becoming a problem, especially in the black oak group. Southern red and black oaks are particularly susceptible.

I don't know any thing about your subspecies, but many of the more northern lots of white elm (U. americana) will start from a root piece. You dig up a root, carefully, in spring and cut a piece about pencil diameter with a feeder root. Pot the cut end at soil level, and it may grow shoots at the top. It's important to pot it right end up, distal end down, end closer to the original trunk, up.

Worth a try to see what happens.