Maryland Invasive Plants Prevention and Control


A Notice of Final Action for the Maryland Invasive Plant Regulations was published in the April 1, 2015, Maryland Register​. These regulations establish lists of Tier 1 and Tier 2 invasive plants, and require that signage be placed near retail displays of Tier 2 plants. The regulations also describe mechanisms for listing and delisting invasive species, procedures for the disposal of Tier 1 plants, and an outline of conditions under which the Secretary’s approval may be given for otherwise prohibited activities.  


Invasive plants threaten native plant health and biodiversity in both agricultural and natural systems in Maryland. Many of these problematic plants are imported, bred, distributed, and promoted for sale in the landscape and nursery industries. Maryland’s Invasive Plant Advisory Committee (IPAC) was established by legislative mandate in October 2011. The IPAC’s primary responsibility is to advise the Maryland Secretary of Agriculture on regulating the sale of invasive plants and preventing them from entering Maryland or from spreading further into the state. Using a scientific weed risk assessment protocol, IPAC classifies invasive plants as Tier 1 or Tier 2 and recommends regulations to reduce the risk of invasive plants in Maryland. View the list of IPAC Members​.  

Invasive Plant Lists and Requirements

View the fullMaryland Invasive Plant List

Tier 1 Invasive Plants  

The following plants were designated as Tier 1 invasive plants on April 24, 2019.

  • Corydalis incisa (Incised fumewort)

Restrictions: Except as provided below, a person may not propagate, import, transfer, sell, purchase, transport, or introduce any living part of a Tier 1 invasive plant in Maryland. These restrictions do not apply to the transfer, lease, sale, or purchase of real property on which an invasive plant is located.


A person may conduct a prohibited activity if:

  • They receive approval from the Maryland Secretary of Agriculture before conducting the activity. A Tier 1 Request Form must be submitted to the Secretary for review.

  • Approval may be given if the activity is for the purpose of: 

  • Disposing of the invasive plant;

  • Controlling the invasive plant;

  • Using the invasive plant for research or educational purposes; OR

  • Exporting the invasive plant out of Maryland.

Tier 2 Invasive Plants  

The following plants were designated as Tier 2 invasive plants on June 30, 2020.

  • Aralia elata (Japanese angelica tree) 

  • Berberis thunbergii (Japanese barberry)


  • A person may not sell or offer for sale Tier 2 invasive plants at a retail outlet unless the retail outlet posts in a conspicuous manner in proximity to all Tier 2 plant displays, a sign identifying the plants as Tier 2 plants. Required insignia can be found under Information for Nursery & Landscape Professionals on the right-hand side of this page.

  • A person may not provide landscaping services to plant or supply for planting a Tier 2 invasive plant unless the person provides a list of Tier 2 invasive plants to its customer​.


A person that requests a declassification of a plant as Tier 1 or Tier 2, including cultivars of specific plants presently listed, must submit a written request to the Maryland Agriculture Secretary that includes:

  • Name of the Requestor

  • Contact Information

  • Scientific name of the plant

  • Detailed justification of the request


  • The Secretary may impose a civil penalty not to exceed $500 for each violation.

  • Title 12 Criminal Penalties

Legal Authority: Md. AGRICULTURE Code Ann. § 9.5-101 et. seq.​​​​

Primary Contact

Kimberly Rice
Program Manager 
Plant Protection Section 
Phone: (410) 841-5920 

IPAC Meeting Minutes

Weed Risk Assesments

​Information for Nursery & Landscape Professionals

Required Tier 2 Invasive Plant sign insignia. Must be minimum of 5” tall x 7” wide and reproduced in black on a bright yellow background. 

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