Almost all the plants on my place have thorns and I have to say that the Honey Locust or thorny locust is my arch enemy. They can really teach you patience while clearing. Instead of bulldogging an arm full and dragging to the brush pile, you have to carry one branch at a time and the branch will need to be cut short so it's easy to handle. My old ford tractor had to be fitted with solid filled tires to avoid making the tire repair shop owner retire early.
The Osage Orange can be a real buggar to deal with and keep pleasant looking, but I really like the fact that they supply plenty of late winter forage for the squirrels. Once the walnuts and acorns are ate up, they come out to get the hedge apples in January which yields some nice winter hunting.
Besides the pesky thorn trees, poison ivy, cats brier, grape vines, multiflora rose, and stick tights can all get small tree size at my place. I just cleared an old fence line and found a poison ivy vine 2 inches in diameter and with the support of a dead tree it grew 8 feet tall. I can usually avoid the ivy rash, but not this time! I am waiting on spring now to continue that fight with herbicide once it tries to come back from the roots.
