Not all locust trees are poisonous to humans. Only the black locust trees contain a toxic substance called toxalbumin.
It can be fatal when ingested although researchers establish that being poisoned due to contact with black locust trees are rare.
The toxic component of black locust trees is concentrated in the bark, branches, and even leaves of. When ingested, they cause severe stomach pain, vomiting, and diarrhea to children, pets, and even livestock.