Md. Code, Nat. Res. § 5-421

(a) (1) The Department may permanently revoke or temporarily suspend the license of any licensed tree expert who: (i) Is found guilty of any fraud or deceit in obtaining the license, or guilty of negligence or wrongful conduct in the practice of tree culture or care; (ii) In the Chesapeake and Atlantic Coastal Bays Critical Area, as defined under § 8–1802 of this article, fails to comply with: 1. The terms of a State or local permit, license, or approval; or 2. Any State or local law, an approved plan, or other legal requirement; or (iii) Fails to maintain liability, property, or workers’ compensation insurance as required by law. (2) The Critical Area Commission shall notify the Department of any tree expert who fails to comply with any requirement under paragraph (1)(ii) of this subsection. (b) The Department may promulgate rules of ethics and temporarily suspend for a period not to exceed two years the license of any licensed tree expert who violates the rules of ethics. This power of suspension is in addition to, and not in limitation of, the power to revoke or suspend provided in subsection (a) of this section. (c) A license issued under this subtitle may not be revoked or suspended until after the licensee has a hearing before the Department. Notice of the cause for suspension or revocation and the hearing date shall be sent to the licensee at the last known address of the licensee by registered or certified mail at least 20 days before the hearing. The nonappearance of the licensee after the required notice has been given, does not prevent holding the hearing. (d) The Department may reissue any tree expert’s license previously revoked under rules and regulations it prescribes.