Invasive Plants & Insects

National Invasive Species Awareness Week logo
5 Ways to Participate in National Invasive Species Awareness Week
Keep an eye out for invasive species, from February 20—26 and beyond.
National Invasive Species Awareness Week (NISAW) is being celebrated February 20 – 26, 2023. Learn More
Intern pulling pepperweed
Nature Groupie Interns Discover and Remove Perennial Pepperweed, an Invasive Species
UNH students gain field experience and help protect the N.H. Seacoast through Extension’s summer internship program
UNH students gain field experience and help protect the N.H. Seacoast through Extension’s summer internship program. Learn More
European barberry
The first signs of spring...spotting invasive plants
As the weather warms and our days stretch longer and brighter, we begin to see and hear the bustle of the natural world picking up all around us. The ... Learn More
Glossy buckthorn (Frangula alnus)
Invasive in the Spotlight: Glossy Buckthorn
A canopy invader best controlled with early detection
A canopy invader best controlled with early detection Learn More
european barberry
Invasive in the Spotlight: European Barberry
While not very common in New Hampshire, it is highly invasive and has the potential to become a significant pest
While not very common in New Hampshire, it is highly invasive and has the potential to become a significant pest Learn More
Japanese honeysuckle
Invasive in the Spotlight: Japanese Honeysuckle
While not a serious problem in New Hampshire, Japanese honeysuckle is a major pest in other parts of the northeast.
While not a serious problem in New Hampshire, Japanese honeysuckle is a major pest in other parts of the northeast. Learn More
autumn olive
Can invasive species be beneficial for wildlife?
A Question of the Week
A Question of the Week Learn More
japanese knotweed in bloom
When is the best time to control Japanese knotweed?
A Question of the Week
A Question of the Week Learn More
Purple Loosestrife
Invasive in the Spotlight: Purple Loosestrife
A beautiful menace in wetland habitats
A beautiful menace in wetland habitats Learn More
Dr. Josef Gorres in the forest
UNH Extension Hosts Invasive Earthworm Expert in Portsmouth
The quick-moving, voracious “jumping worm” in N.H. gardens and forests and you can learn about it at a seminar on July 26
The quick-moving, voracious “jumping worm” in N.H. gardens and forests and you can learn about it at a seminar on July 26 Learn More