Updated: Feb 17, 2022
This fall, I am participating in the UNH Cooperative Extension’s Master Gardener Program and I am absolutely loving it. This week one of the sessions was on invasive species in New Hampshire and I was astonished to learn that many of the plants and trees I see on a daily basis are not only invasive, but they are incredibly destructive to our native species.
Right now, looking out my window, I can see Oriental Bittersweet, which chokes trees and pulls down their branches. I can see Honeysuckle, which pushes out native shrubs and understory plants. And I can see a tiny, but beautiful Burning Bush, which also outcompetes natives.
Driving down my road, I see giant stands of Japanese Knotweed, which emits a chemical into the ground, essentially killing nearby plants and is almost impossible to kill, once it gets established. I was astonished to discover that nearly half of the species I saw growing along the Merrimack River in Concord were noxious invasives. It was pretty disheartening, honestly.
What can we do?! My son and I have big plans for taking on the invasives in my own vicinity, but what can we do about invasives along the roads and especially along the river? Your first step is to learn what invasive species we have here in New Hampshire. This is the very useful guide we were given in class. UMass Amherst College of Natural Sciences put out a video series that shows you how to identify the worst offenders. Or, if you don’t have time for videos, this poster shows enough parts of the plant for solid identification. You can also download an app at https://www.eddmaps.org/ that lets you act as a citizen scientist and help researchers to study the progress of invasives.
Once you’ve identified an invasive species, you should report it to EDD and then think about your next steps. In some cases, especially if the plant is in your own yard, you may be able to take care of it yourself. Digging up roots, pulling down vines, and properly disposing of the reproductive parts of of the plants (usually flowers and berries, but sometimes also roots) will go a long way toward eradicating a local infestation. If the plant is stubborn, you can call on an expert to do it for you. Either way, you’ll want to keep monitoring for a return of the plant. They aren’t called invasives for nothing!
Oriental bittersweet climbs up trees, chokes them, and finally kills them. It is EVERYWHERE along highways and rivers in New Hampshire.
But what if the infestation is big and it’s not in your own yard or close by? Again, the first step is to report the infestation to EDD and to the UNH Extension. This information helps researchers know how the invasive species are progressing and where they are. Next, you can get together a group for a work day, using these resources (there are even tools you can borrow!). Interested in helping combat invasive species, but don’t want to go it alone or start your own group? You can always join a local workday or suggest one.
Burning bush is easy to find in the late summer and early fall! Photo credit: http://ctnofa1982.blogspot.com/
Invasives are a reality here in New Hampshire and ignoring them is not going to make them go away. Our best option is to be proactive and to work together to keep New Hampshire green!
Cover Photo credit: https://www.gardeningknowhow.com/