These trees/shrubs have heart shaped leaves. They look like they were planted where they are, but I’m told they are weeds. If anyone can tell me what they are and if they’re worth saving//transplanting, I’d appreciate it! They and I are in North-central Oklahoma. Thanks!
Heart-Shaped Leaf Tree
Those all look like Eastern Cottonwood - Populus deltoides. I suspect nature planted each of those, by their wind-blown seeds drifting in from parent trees elsewhere.
Only you can decide whether they are worth trying to transplant. I'd suggest that you will find new ones annually, and that if you've never transplanted anything before - you should start with little trees first. As you gain competence, experience, and success - then move on to bigger and better things.
Cottonwoods are great big trees, eventually. Not a tree to keep near structures, patios, pavement, and the like. They'd prefer to reach old age near constant water supplies, like streams, creeks, rivers, floodplains, etc. They grow exceedingly fast, thus the reason to move them while little to a good permanent spot where they will provide value and not create havoc.