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​Controlled Plant & Noxious Weeds

Controlled Plant List:

A controlled plant is a plant species or subspecies that has been designated by the committee as a controlled plant and is regulated to prevent uncontained growth and to negate undesirable characteristics.

  • Hemp - Cannabis sativa L and any viable part of that plant with a delta-9 THC concentration of not more than 0.3% on a dry weight basis.

PDA regulates hemp growing and processing through the Hemp Program.

About Noxious Weeds

Noxious weeds are identified as a plant that is determined to be injurious to public health, crops, livestock, agricultural land or other property and cannot be sold, transported, planted, or otherwise propagated in Pennsylvania.

Weeds are placed within one of three classes, Class A, B, or C based on spread and eradication potential and includes the Federal Noxious Weed list by default as Class C weeds.    

Class A Noxious Weed-

        • Is established in Pennsylvania
        • Is geographically limited
        • Is intended to be eradicated

Class B Noxious Weed-

        • Is widely established in Pennsylvania
        • Cannot feasibly be eradicated

Class C Noxious Weed-

        • Is not known to exist in Pennsylvania
        • Poses a potential threat if introduced into the Commonwealth
        • Is listed on the Federal Noxious Weed List


Noxious Weeds List:

Class A Noxious Weeds

Class B Noxious Weeds

Class C Noxious Weeds

    • Water soldier - Stratiotes aloides 

Submit a Noxious Weed complaint.

Plants that have been voted on and approved by the Controlled Plant and Noxious Weed Committee will become official 60 days after publication in the Pennsylvania Bulletin