Never attempt to treat excessive weed infestation with chemicals, other biological controls or mechanical cutting. If weed growth has increased on your shoreline, the New Hampshire Department of Environmental Services can assist in identifying a weed and helping you manage its presence.

Please take a sample of the weed, place it in a Ziploc bag with a moist towel, note where the sample was taken from, and deliver the sample to the NHDES office in Concord.

NH Department of Environmental Services
Exotic Aquatic Species Program
29 Hazen Drive, PO Box 95
Concord, NH 03302-0095
603-271-2248

DES Exotic Species Website
Please Note: you will be directed to the NHDES website,
please allow pop-ups