Useful trees for frontier living: Elm
Here's an excellent youtube video for tree identification purposes. Many times people have the knowledge, or some are great teachers, or some are good at camera work and editing, but rarely do they have all of those talents. It's why a team created a film usually.
This one talks about three wild edibles: the samaras of the elm (seed pods) contain a good source of protein, the basswood (lime tree) buds which are good, and the maple seeds you probably played with as a kid which are packed with nutrition.
Another video which is solely about the slippery elm:
Elms, like pines, have a layer called the cambrium which has a lot of protein in it plus vitamins and minerals. In Norway, there was a famine, and they ended up eating this and saving a lot of lives. The First People ate it too. Of course, it doesn't taste great, but people noticed that that layer produced a slippery substance, something that is scientifically categorized as mucilagenous. That means it's perfect as a salve, and it's used today in herbal teas to coat a sore throat, and it's so very excellent when aching. It also was used for wounds by tribal people. Today it is useful for people with irritable bowel syndrome, a condition which is caused by stress and scrapes away a portion of the intestinal mucus, and this causes issues irritation in that region.
If one knew how to harvest the bark and seeds, then you'd feed your family plus help them medicinally.
In addition, the way that an elm forms it's wood, it is a whirl of growth, and so it was used to make wagon wheels, excellent bows when yews were not available, or any lumbar that resisted splitting.
[link to en.wikipedia.org
[link to www.eattheweeds.com