Perennial Pepperweed Partnership


Pepperweed (Lepidium latifolium) is a relatively new invasive plant to Maine and New Hampshire, though it is well established just to our south in Massachusetts. It is a threat to our native plants, animals and landscape. UNH Extension is collaborating with the US Fish and Wildlife Service (USFWS) on a new project to map Pepperweed in Maine and New Hampshire and work towards eradication.

From 2021 to 2022 the partnership will work collaboratively in Maine & New Hampshire to build a comprehensive map of existing populations, support ongoing eradication efforts and coordinate public engagement. If you have questions about Pepperweed in Maine, please visit the Maine Natural Areas Program webiste.


We need help building a comprehensive map of where Pepperweed is in Maine and New Hampshire.

1. Learn To Identify Pepperweed.

Pepperweed can be found in coastal salt marsh and upland roadsides. It grows 1-5 feet tall and flowers mid-june to mid-August in Maine and New Hampshire. Below is a card with several photos and helpful tips for identification:

Identification Card

Identification Video

2. If You See it, Report it.

Think you spotted Pepperweed? It's easily to report it, there are simple instructions below for Maine and New Hampshire:

Report a Sighting in Maine

Report a Sighting in New Hampshire



We hosted a webinar in early June of 2021 to explain this partnership, identify opportunities to learn about and collaborate on monitoring and eradication efforts. You can watch the recording of the zoom presentation here.


Malin Clyde
Community Volunteer State Specialist
Assoc State Specialist
Phone: (603) 862-2166
Office: Cooperative Extension, Nesmith Hall, Durham, NH 03824