Ala. Code § 42-2-2: Application.

The application of the United States or its agent must be in writing, verified by the oath of an agent or attorney, and must state with certainty the uses or purposes for which the land is to be taken or the interest or easement therein to be acquired, and must state the name and residence of the owner if known or, if unknown, must show that reasonable diligence has been used to ascertain the same.