Md. Code, Nat. Res. § 5-414

Any uniformed forest officer, or any law enforcement officer may stop any truck, trailer, or other vehicle engaged in the transporting of the evergreen trees, shrubs, or boughs described in §§ 5-412 and 5-413 of this subtitle, other than a truck or trailer licensed for and engaged in interstate commerce, in order to require the driver or operator to produce the bill of sale or identification of ownership required by those sections. The driver’s failure to have and produce upon demand the bill of sale or identification is a violation of this subtitle. However, an accused may not be convicted if he produces, within ten days from the date he is formally charged, the required bill of sale or identification.