Canterbury, NH – Over the years, Riverland has become overrun by invasive species. The crew at Riverland on the Merrimack made a start this summer to cut them back, mow them down, and otherwise begin a program of remediation and control. We are learning as we go. We decided to blog about it, because we figure other people can learn right along with us about what works and what doesn’t work.
To our knowledge, we have five, vegetative invasive species: Asian Bittersweet, Multi-Flora Rose, Autumn Olive, Buckthorn, and Poison Ivy. This is only what we know about. We could use the help of an expert to map out the true extent of the problem and to create a credible control plan.
We also know that these plants have a big head start on us. We can see them everywhere, of course, but that’s not very scientific. Fortunately, NH Fish and Game has documented the scale of the problem for us. Their website has a map of “Priority Areas for Invasive Plant Management” by town. From their website, click on “Find Hotspots in your Community” and then, click on “Canterbury.”
Invasive plant management is a priority where ecologically important areas overlap with areas from which invasives are likely to spread. Riverland is a rare riverine habitat, prime farmland, and right on the river; invasives can easily spread downstream. To find Riverland on the map below, locate where the lower-left corner of the town line meets the river. Riverland is the property bordering the two, oxbow-shaped ponds.
Step 1: Mowing:
James Farquhar, bless him, does most of the mowing. He mowed the Riverland fields once in 2016, our first year here. The fields were a riot of golden rod and milkweed and had not been mowed in years. That’s him on our antique 1949 Ford 8N tractor in the photo below. Jon Hall of Gilmanton truly understands old tractors and is teaching us how to keep the old girl running. Fortunately, the bush hog is newer, because it is working really hard.
In 2017, James mowed the fields twice, and in some areas, three times. You can see in the 2017 photo that the mowing is beginning to bring back the grass and discourage the goldenrod/milkweed/ et. al. We estimate it will take another two summers of extensive mowing to bring the pastures back.
Step 2: Hacking back the jungle:
Autumn Olive and Asian Bittersweet are a bad combination. Bittersweet wants to climb and the autumn olive obliges by providing the scaffolding. These clusters of invasives can get to be two stories tall, and then climb over the top of nearby trees.
James, Jon, and son, Ben, spent two days hacking back the jungle shown in the photos below. As you can see from the photos, we found a truly beautiful Butternut tree in the center. The Butternut is a North American native which produces rich, butter-flavored nuts in late October, some years, when it feels like it, once it is 7-to-ten years old.
We figure other people may have an invasives problem also, so we are going to share how the crew brought this jungle down. This is just how we did it. We aren’t recommending any of these techniques per se. You will figure out your own path and take your own risks.
First, we got out the chainsaws and started hacking at the vines and anything else we could reach, wading deeper into the cluster as way opened. We kept a sharp eye out for trees we might want to keep and stuff falling from overhead. Slashing with a chainsaw in mid-air is dangerous, especially if you are standing on unstable slash. Some experience with a chainsaw is warranted.
Second, we got out the old garden rake and pulled the vines and pieces of branches out into the field as they rained down. You will see below why we raked. Then we cut some more autumn olive branches and bittersweet vines and raked some more until we could walk around the tree we discovered in the middle of the mess.
Third, we went to the back of the barn for our long-handled pruning tool and snipped the Bittersweet vines as high up as we could reach in the tree. Some of our vines were inches in diameter.
Fourth, Ben got a good hold on the now dangling bittersweet vines, and pulled. I mean, he really pulled. He had to be very careful that the branches did not break before the vines came down. We were not able to pull all of the vines out of the tree, so we left them there to turn brown and fall out in their own time. It was a good thing that the bittersweet had not yet set its berries, or they would have hung up there until some opportune moment to fall and reseed the bittersweet.
Fifth, you may wish to climb the tree in celebration, after the tree is free of smothering vines and undergrowth.
Sixth, we drove over the branches and vines and vegetation with our bush hog a few times to chop them up so they will compost in place. Bush hogs are amazing machines. Our Woods M5 can chop up branches up to about 3 inches in diameter. Stay way back. The shards fly like shrapnel.
It is probably best NOT to mow over branches when someone is sitting in the tree checking their messages.
Seventh, we celebrated our hard work in full recognition that we will have to keep mowing around this tree, probably forever, to keep that mess from growing back.
Step 3: Removing obstacles to mowing and climbing frames.
As you can see in the photos below, we had a decrepit shed crowned in bittersweet. Although it was pretty in the fall, it was just one more thing to mow around and something else the bittersweet could climb. Did I mention it was rotten and didn’t have a roof? It had to come down.
First, Jon and Ben pulled as many walls of the shed as they could wiggle free. Fortunately, the shed didn’t offer much resistance.
Second, when all else fails, try brute strength. Let’s see how much comes down if I really pull.
Third, when brute force is not enough, exert leverage on the corner that remains. This corner was entirely bound by bittersweet , which twined around the shed and the fence that ran nearby. The last bits of shed needed to be chopped free of the bittersweet before it could be entirely dismantled.
Fourth, James hauled most of the dismantled shed to the dump. The plywood walls showed signs of once having been covered in red paint. We didn’t know if that was lead paint and so, hauled it to the dump rather than burning it.
Step 4: Future work on invasives at Riverland…
The work of managing invasive species within the farm perimeter is going to take constant effort over many years. The autumn olive, mowed often enough, will probably eventually give up. And bittersweet with nothing to climb generally spreads across the ground, where it is a lot easier to mow…
However, it’s going to require endless mowing. We cut/mowed a large autumn olive bush out in the field in late June. The photo below shows how much it had grown back from the roots by late August.
This fall, we hope to continue to clear the plants climbing our barns, for the sake of the buildings. It is time-consuming to pull bittersweet off buildings, because the little tendrils need to be pulled off by hand. James has half cleared one barn.
We also hope to continue working on the autumn olive bushes that grow all over the river edge of the field. They need to be chopped down one-by-one. The photo below gives some idea of the scale of the problem.
Next year, we will continue the mowing, to maintain the progress we made this summer, and to start to clear and to take down the internal fences, which are too hole-y to keep livestock in or predators out . We will also continue clearing the inside of our perimeter fence, working toward the day when it can be replaced also.
Until then, peace….