Trees that have thorns on the trunk are the honey locust and the coral tree. The honey locust, in particular, is notorious for the long and vicious thorns that grow on its trunk.
The thorns on its trunk and branches make the honey locust not as popular in parks or gardens as it might be. This is despite the sweet taste of its seed pods and the fact that the tree is deer-resistant and can tolerate heat, drought and poor, salty soil.
The coral tree is grown for its spectacular red flowers, in spite of the fact that both its trunk and its branches bear thorns. Native to southern Africa, it has been introduced into India and the United States.