The District of Columbia Code Title 42 Chapter 32 Section 3 allows a landlord to terminate a tenancy that is no longer (or has never been) under an active residential lease agreement by using the following notice requirements:
Tenancy at Will (month-to-month)
A tenancy at will may be terminated by 30 days notice in writing by either landlord or tenant.
DC Code § 42–3203.
See also DC When a Notice to Quit is Not Required.