Md. Code Ann., Tax-Prop. § 9-233
(a) The Mayor and City Council of Baltimore City or the governing body of a county or municipal corporation may grant, by law, a property tax credit against the county or municipal corporation property tax imposed on property owned by the Audubon Naturalist Society of the Central Atlantic States, Inc. that is used solely for:
(2) the maintenance of:
Added by Acts 1999, c. 185, § 1, eff. June 1, 1999.