Md. Code, Nat. Res. § 5-418

(a) The Department may examine an applicant for license as a tree expert and pass upon the competence of the applicant. It shall issue a “tree expert” license to any applicant, who: (1) Pays the fee provided in § 5–419 of this subtitle; (2) Has attained 18 years of age; (3) (i) Has had 2 years of approved college education in forestry, arboriculture, horticulture, applied agricultural sciences, or the equivalent education and a minimum of 1 year of experience with a licensed tree expert in Maryland or with an acceptable tree expert company in another state; or (ii) For at least 3 years immediately preceding the date of application has been engaged continuously in practice as a tree expert with a licensed tree expert in Maryland or with an acceptable tree expert company in another state; and (4) Has passed the examination given by the Department. (b) Every licensee shall carry and show proof of liability and property damage insurance, in the form and amount required by the Department at the time it issues the license. The licensee shall maintain the insurance protection for the period the license is in effect.