Md. Code, Tax - Property § 7–304

(a) Property is not subject to State property tax if the property is:

(1) owned by a land trust as defined in § 3-2A-01 of the Natural Resources Article that is certified by the Maryland Environmental Trust to be a land trust in good standing and to have a cooperative agreement in effect; and

(2) used:

(i) to assist in the preservation of a natural area;

(ii) for the environmental education of the public;

(iii) to conserve agricultural land and to promote continued agricultural use of the land;

(iv) generally to promote conservation; or

(v) for the maintenance of a natural area for public use or a sanctuary for wildlife.

(b) To qualify for an exemption under this section, a land trust shall obtain a written certification every 5 years beginning July 1, 1998, or as scheduled by the Maryland Environmental Trust.