Another piece of my american elm broke off. There are some root looking parts. Could I cut off this section and put it in dirt or sand to make a new tree? I will post a photo of it.

Photo of elm

I ended up cutting this limb down and planting the root hairs with the stump. Hope it works.

Have you considered coppicing or pollarding it? It might rejuvenate the tree. FYI, livestock really enjoy the leaves. Protein content at least 16%.