I went back to the JKW control area this evening with my son Chris to see where things stood and to do a little maintenance work. It was pretty discouraging. Between rain showers, we spent nearly an hour but probably weren’t able to cut down half of what has grown up again. Particularly on the fringes, the JKW has grown back tall and tough. It is growing quite thickly in the cracks between the plastic sheets, and is even starting to grow through holes in the sheets in places. Doesn’t look like much has been done there since my last clearing effort two or three weeks ago, except perhaps some in the area immediately to the right of the plastic sheeting. Chris wielded the weed whacker, and I pulled up as much JKW by the roots as I could in the plastic sheeting area. Between 7:30 and 8:30 p.m. the tse-tse flies were swarming viciously, and finally we were driven out. My back had healed up a bit, but this type of exercise did not help it. The weed whacker is still functional but it needs to have its screws and nuts tightened up. My impression is that the area that was dug up and covered in plastic will produce much better results than the area that is just being cut. It seems like the greater amount of up-front work is worth it in the long run.
Bottom line: THIS PROJECT IS OUT OF CONTROL, and needs a healthy dose of labor.
I went back to the JKW site again last night and finished the project of pulling up, by the roots, all the JKW growing between the black plastic sheets and the marsh. This was (quite literally) back-breaking work, but the results, I think, are great.
Picking up on and extending Mike’s suggestion, this really would be an opportune time to cover over the area I have now cleared with more black plastic sheeting. Why just let it all grow right back again?
For that matter, I think it would make sense to re-cover the whole area better than we did the first time. One of the obvious improvements, it seems to me, would be to try to cover the area with significantly more overlap between sheets, so that we won’t have the ever-widening gaps that we experienced the first time. We can certainly re-use the plastic that is there, but we would need, I think four or five new sheets.
Since Mike is quite appropriately up to his ears planning for the boardwalk construction, I may just try to do this myself one of the next two evenings, or possibly over the coming weekend. I trust no one would have any objection to purchase of another box of plastic sheeting.
If anyone wants to help with this (Don?), maybe we could arrange a time to meet. It shouldn’t take more than half an hour.
Don and I did some more work on the JKW site, as planned, last Friday evening.
We covered with new sheets of black plastic the entire area between the bottom of the existing plastic sheets and the marsh. Before laying down the new plastic, we rolled back the bottoms of the existing sheets eight or ten feet, pulled out new stalks of knotweed that were growing underneath (they were pale and pretty sickly), and then layered the old sheets back over the top of the new plastic sheets shingle-style so the water would run off.
Spotted underneath the plastic as we were rolling it back: one field mouse and two garter snakes (amazing the mouse was still alive).
One other issue we had hoped, but were not able, to deal with is the gaps that have emerged between the existing plastic sheets, where the JKW had regrown profusely. Plan A was to remove all the plastic sheets and re-lay them closer together, with more substantial overlap. Because of all the debris on top of the sheets, however, this proved impracticable. Plan B was to simply add a new piece of plastic sheeting on top of each gap. We think this would have worked just fine, but it turns out we had only enough plastic sheeting to cover the bottom area (I mistakenly thought there was more than one sheet in each of the two packages I bought), so we had to abandon this plan, at least temporarily, as well.
I have since bought several more roles of plastic sheeting, and when I get a chance, I will try to lay it down over the gaps, thus completing the project.
I also chopped back some of the now-huge JKW stalks growing on each side of the cut area, but once the JKW gets this tall, it is very difficult. If we don’t do something about this JKW on each side of the project, it will eventually spread right back into the area we have been working on.
The bottom line is that the JKW control area is now in excellent shape (at least for the time being). Go by and take a look sometime.
I am happy to report, following one more visit to the JKW site yesterday evening with Laurel, that the project that I characterized a few weeks ago as “out of control” is now very much under control.
The first task that Laurel and I tackled was to cover the gaps between the sheets of plastic. Since my visit with Don last Friday, I had bought several more rolls of black plastic. Two of the rolls were 6 mil plastic sheeting, which is thicker than the 4 mil sheeting Don and I put in last week, and substantially thicker than the sheets we originally used, which must have been 2 or 3 mil. Being thicker, this should be much tougher and more resistant to puncture and tearing, and possibly also a bit more impervious to light. I also bought two more rolls of 4 mil sheeting.
We used the 6 mil plastic to cover the gaps. Since we did not need a full size sheet to cover each gap, we cut the sheets in half, thus making two rolls of 6 mil sheeting do the duty of four. With the four half-sheets, we were able to cover thoroughly all the gaps. By trimming, we also had enough plastic left over from these two rolls to cover some of the areas where holes had broken through in the original sheets, and JKW was growing through the holes. We took pains to weight everything down carefully with stones. I hope this will keep the sheeting well-anchored for the duration of the summer (however, because there is a potential for vandalism, and on the steeper slopes it is pretty easy for the stones to roll down the bank, we should periodically check that the sheets are secure).
We then uncovered the large waste pile that had been covered with blue tarp, under which the JKW seems to have been growing fairly profusely. After cutting/tamping down the new growth, we covered the entire pile with a sheet of 4 mil black plastic sheeting (cut in two to fit), and then put the blue tarp back over the black plastic cover. Hopefully, this will block any light that might penetrate through the blue tarp and stop any further growth in the pile.
That leaves one more roll of 4 mil plastic sheeting that is 20′ x 25′ (this is huge) to use for patching or as otherwise might be needed.
In the areas where we have employed the cut-cut-cut method, the JKW growth for the first time seems much more subdued. It must be that cutting later in the growing season has a more terminal effect on the JKW than cutting earlier in the summer. That is not to say that the JKW in this area won’t grow back — I am sure it will, and that we will have to cut it all back down at least one more time. But the re-growing JKW in this area did not seem particularly healthy, and Laurel and I felt as though we finally had the enemy in check.
The bottom line is that the project area is now completely flattened, and the plastic cover area is almost entirely devoid of JKW (except for some pale growth that continues to occur underneath the original plastic sheets). This makes for quite a stunning vista of the Meadow, for which passers-by appear to be extremely appreciative.
My major concern at this point is that the JKW that is growing profusely for a hundred yards or so on each side of our cleared area will continue to be a problem, and will invade back into our cleared area in short order. Obviously, we cannot take on too much, or it will be hopeless. It may be, however, that an hour or so with Mike’s gas-powered weed cutter would help to put the bordering JKW more on the defensive.
One more issue we will need to address sooner or later is whether to leave the plastic sheeting down for the winter, or try to plant something in the area this fall. My current sense is that we should leave the plastic down at least through this winter and next spring to try to completely demolish whatever remaining rhizomes may exist underneath. Does anyone know how long the rhizomes might survive under these conditions?
Thanks to Don and Laurel, as well as to anyone else who has been working between times on this project. I think we have done the best we can at this point. It will be very interesting to see how things develop. I hope these periodic reports will be of some interest in documenting the progress of our efforts. David, if we had a JKW page on our web site, would it make sense to post these reports as a kind of a log?
I stopped by the JKW site Thursday evening.
The good news is that the area covered in plastic is still well-covered and doing fine. The bad news is that the JKW on the sides, particularly the right-hand side facing the meadow, is already starting to grow back up again. I would say it has grown at least a foot or two since Laurel and I last left it essentially flattened a week ago.
I cut all the new JKW growth on the bike path side of the fence. I also cut everything for about 5 or 10 feet on the other side of the fence. Finally, I attacked and cut back some of the 7′ high JKW thickets on the far left side of the project area, although there is a great deal more still there.
I think we’re going to have to just keep cutting and cutting the uncovered areas of JKW. It sure isn’t showing much signs of diminished strength.
This early evening Barbara Strell, Sarah Garner, and I worked on the JKW site for somewhat over an hour. A man named Kenny joined in after some encouragement from us. Someone else had already cut down the three-foot-high JKW growing up between the black plastic and the pile under the tarp — thank you.
The four of us worked on the following:
- We pulled up some of the short new shoots just west of the tarp.
- Over on the other side of the plastic, we cut back the knotweed along more of the margin with the marsh, right back to the purple loosestrife, and hauled the stalks up the hill where they will get more sun. We also pulled up some of the young new shoots just up the slope from there.
- We lifted up the tarp and found that the stuff under it is really foul, almost completely brown and just a few thin, whitish anemic stalks that don’t amount to much. My suggestion at the last meeting of hauling that stuff out to where the sun can get at it seemed a less appealing idea tonight, and we didn’t get into it. However, it may be the best way to get this stuff to burn eventually. If we do it, we will probably need garden spades and wheel barrows, at least for some of it.
Sarah and Barbara said they can do some additional work in the near future, which is great. I will be out of town from this Thursday evening until Wed morning of next week, so it will be a while before I can do more.
Buckthorn: On the west side near the marsh we have three or four glossy buckthorn plants in TREE form, with single stems and a lot of branches and leaves that form pretty high off the ground — almost like lollypop trees.
I would like to cut those down, since they are an invasive species and are creating lots of berries (and seeds), and they do block part of the view.
Any thoughts on this?
Just for the record, and to keep our “log” complete, I spent a fair amount of time last Saturday evening at the JKW site. I cut down all the re-emerging JKW on the right-hand side, facing the marsh, all the way down to the marsh line. I also cut another twenty or thirty feet or so into the 7-8′ high bordering JKW on the right-hand side — but there is still more to go.
Someone (I assume Don) has been keeping after the “cut” area on the left-hand side, so that seemed pretty well controlled.
At some point before the end of the summer, it would be great if Mike could borrow that weed cutter and we could cut down the rest of the bordering JKW. David, do you have any sense of the timing on that to maximize impact on the rhizomes?
A footnote: On these late mid-summer evenings, just before the sun begins to set over the marsh, the vista over the marsh — now in full bloom with purple loosestrife — is stunning. The loosestrife may be an invader, but unlike the JKW it sure is attractive. The experience walking through the marsh on the newly constructed boardwalk as the last sun rays light up the meadow is also quite impressive. What an improvement.
Current Conditions (Summer 2005)
With many hours of volunteer work the area has been cleared of JKW. But shoots continue to come up from the underground rhizomes and the area will require continued vigilance and work before the JKW can be said to be controlled. The picture below shows the view from the bikeway on August 10.