My Worst Decision...and how do I get rid of all these pieces of landscape plastic?!?

I'm sharing this largely in the hopes that I'll save someone else from the disaster I'm in, and maybe, just maybe, someone will have some ideas on how to clean this all up.

Here's the backstory: When we moved onto our property 5.5 years ago, we found bindweed. We knew bindweed as a horrid monster of a plant, and did not want it taking over our property. The first year, I tried smothering it with lots of cedar branches, hoping to shade it out. The cedars lost their needles and the bind weed grew up between the branches and was hard to pull up...and salmonberry grew up, too, making it even harder to pull up. I tried spraying it with vinegar--it didn't really do that much. The next year it came back twice as strong. My husband wanted to nuke it with Round-up, which I was totally opposed to. I was pregnant with my son, and  we needed a quick solution that would stop the bindweed from spreading. We chose to smother it with black plastic. We thought "we'll just drapw the whole area with black plastic, keep it covered for three years so everything is dead, and then we can rebuild the soil. It's not the best option, but it'll be relatively easy and non toxic" We bought the thickest plastic we could find and covered the whole area.

It was a disaster.

The salmonberries tried to poke through the plastic. Then the rain made puddles on top because it was uneven and then the weight of the water (and the ducks that would climb on the tarp to play in the water) made the salmonberries pop up through. And black berries grew over the top of the plastic. But, we didn't want to take it off, because we didn't want the bindweed to see the light of day. So we left it on for another year....And then last year we started to notice it crumbling. We'd find pieces of plastic a few feet from the tarps. But, I had an infant and there was no way I could carry her into the salmonberry mess to pull out all the plastic. So, it stayed for another year.

Today, I said, "If I don't do something now, this is just going to get worse!" So, I started pulling up the plastic, and was HORRIFIED to see that there are thousands of 1 inch or smaller pieces of plastic under the tarp. AHHHHHH!!! I told my son I'd pay him with ice cream if he'd pick up 50 pieces of plastic (it was 80 degrees today, so I'd need to give him something to cool down after working in the hot sun, anyway. I filled up three x-bags of pineshavings with plastic. I've only got maybe 1/4th of the big pieces of plastic. I have literally NO IDEA how I'm going to get all the little pieces of plastic out of there. They're buried under cedar branches, salmonberry, blackberry, elderberry and grass.

It's a nightmare. If you're thinking of covering something for a few years with plastic to kill weeds, just DON'T. The plastic is so, so much worse than the weed. Instead of weeding out bindweed, I'm "weeding" out plastic and will likely be finding plastic there for the rest of my life. It horrible.

Here's some pictures. They don't really convey the area, but they might

Is the plastic blowing about and thus in danger of ending up in waterways and eventually the sea? If not I'd just leave it. Contrary to urban myth, and as you have discovered, plastic breaks down in the environment. It came from the earth and can go back to it - as far as i know - without causing any problems. Plastic in the sea is a huge problem. This is not plastic's fault or man's fault but the fault of a minority of individuals who allow it.

It seems to me that the easiest way to solve the problem would be to bury it in lots of leaves and wood chips.  I mean deep.  Maybe putting a layer of cardboard down first.  Then plant something.  Maybe grow mushrooms.

While this article goes into toxic stuff I reference it to give you an idea of what plants can do.


http://www.resilience.org/stories/2014-08-11/using-plants-to-clean-contaminated-soil/


Called phyto-remediation, this process has become one of the newest and most promising fields of biology. Similar methods use mushrooms in what is called myco-remediation, or use bacteria and have unfortunate names like bio-sparging, bio-slurping and bio-venting, but we’ll restrict ourselves here to plants.

Mustard greens were used to remove 45% of the excess lead from a yard in Boston to ensure the safety of children who play there. Pumpkin vines were used to clean up an old Magic Marker factory site in Trenton, New Jersey, while Alpine pennycress helped clean up abandoned mines in Britain. Hydroponically grown sunflowers were used to absorb radioactive metals near the Chernobyl nuclear site in the Ukraine as well as a uranium plant in Ohio.

Blue Sheep fescue helps clean up lead, as do water ferns and members of the cabbage family. Smooth water hyssop takes up copper and mercury, while water hyacinths suck up mercury, lead, cadmium, zinc, cesium, strontium-90, uranium and various pesticides. Sunflowers slurp a wide range of compounds – not just the uranium and strontium-90 from radioactive sites, but also cesium, methyl bromide and many more. Bladder campion accumulates zinc and copper, while Indian mustard greens concentrate selenium, sulphur, lead, chromium, cadmium, nickel, zinc, and copper.

Anne is quite right. But I would include mycoremediation in the program, as it is likely already underway.

You will never get all the tiny pieces of plastic mechanically without digging everything up and sieving it out.

I would seriously drop some cardboard (if you are looking to control what remains with mulch), put some wood chips over that cardboard, get a few different oyster mushroom species, make a slurry out of them, and water the woodchips and mulch with the mushroom slurry. I would have any fruiting bodies taken from that spot tested regularly until there remained no trace of heavy metals (mushrooms were used in a sequestration capacity at Fukushima, and they were so loaded with heavy metals, they were toxic) but after several seasons, I wouldn't be surprised if the phyto- and mycoremediation resulted in healthy soil without a trace of contaminants.

But keep us posted, and good luck.

-CK

Anne Miller wrote:It seems to me that the easiest way to solve the problem would be to bury it in lots of leaves and wood chips.  I mean deep.  Maybe putting a layer of cardboard down first.  Then plant something.  Maybe grow mushrooms.

She's talking 3 feet deep not 3 inches. If there is anything I learned from Ruth Stout is that you can't mulch deep enough, and if the unwanteds start poking through, just dump another foot of mulch on top of it.

Oh and it isn't a total disaster. You have a great crop of Salmonberries in the making! They will likely shade out the bindweed. In the meantime think about planting some desirable shrubs / trees among the Salmonberry bushes. They will provide protection as the young trees grow, and will eventually be shaded out themselves.

Your land is undergoing a transition and right now nature is dictating what species play their part. If this area wants to be a forest, then you might not be able to do much about that, but you can determine what sort of forest it will become.

So, today I spent a good two+ hours picking up plastic. I had to wait until winter to do it, because any other season it's nigh impossible to get through the salmonberries/blackberrys/elderberries. As it was, I still got scraped a bunch. But, I got it done! Well, mostly.

When I'd laid down tarp years ago, I'd done four rows of the stuff. Thankfully, the back two rows of tarp were in pretty good shape and I was able--with a lot of effort--pull the sheeting out from under bramble and other plants that were trying to grow on it. Those two sheets came out without breaking into horrific amounts of tiny pieces of plastic. So, at least half of the area I tarped isn't contaminated. WOOT! I'm thinking I can either (1) Let them turn into Bramble Land to make sure they shade out any remaining bindweed (I know there's at least one vine still in there, because I saw it blooming this summer), or (2) Try to turn it into garden beds since most everything under the tarps is dead. I'll probably go with option number 1.

The other two tarps did not fare so well. They ripped and crumbled and the pieces of black plastic are indistinguishable from the salmonberry/blackberry leaves. This area I think I'll just let be "fallow" and try to sprinkles some wood chips and oyster mushroom slurry (I have a bunch of dehydrated oyster mushrooms that I bought in bulk, thinking my family would like them...and my family does not). I'll let the salmonberries and elderberries and trailing blackberries have a hayday, but probably try to contain the invasive blackberries because they're super pokey.

I was FILTHY after cleaning this area up. I smelled of poopy anaerobic bacteria and was covered in duck poopy, leafy plastic slury. It was definitely time for a shower.

Here's a picture of the bags full of tarp. There is one more bag that isn't pictured. What a lot of horrid plastic!

I'll try to take some pictures later of the areas I cleaned out. I did see some mushrooms, and a GIANT web and some white mold-looking stuff.

It very much depends on the particular plastic. In the early 1980s, I tried to kill a patch of Japanese knotweed by covering it with 6 mil black plastic. It took 5 years to kill most of it, 10 before it was all gone, but recently I pulled up most of the remnants which had thirty plus years of leaves and weeds growing on top and creating several inches of rich soil. What was continually buried was still strong and flexible. What was exposed to sunlight had weakened and easily tore into strips.

A few years after this, I tried the same method on another patch of knotweed, but unknown to me they had just changed the formula, and it disintegrated within months just as yours has. They have since made the "6 mil" (now 4.5 mil) plastic much better but still not as durable as the old stuff.

This is a hard lesson that generalizes.  I saw a similar horror story my first week on Permies from someone who used artificial-fiber carpet in a sheet-mulching experiment and filled their garden with colorful plastic perma-fibers.  I buy my dogfood in woven-plastic bags that I have been strongly tempted to refill with soil to use in earthbag sun-capture berms, but my fear of adding those fibers to my soil environment on a permanent basis has kept me from doing it.  

I also do a lot of container gardening in salvaged/recycled plastic containers and I have had to learn to be extremely proactive about moving those containers "along" through the waste stream before they begin to shatter into pieces too small to easily manage.  My many failures to manage this process properly have forced me to get more selective over time about the containers I invite into my container-garden process; fortunately I've had good luck accessioning more durable garden containers over time.  

Ugh! Well, in case anyone in the future looks at this thread wondering if they should use plastic to kill weeds, I can give this advice -- I wouldn't use it, for the obvious reason above. But plastic is useful sometimes in certain situations (eg pond liner). Look for UV-resistant plastic, which will not break down in the sun as fast, but it will eventually.

For future viewers, I'd suggest it might be better for weed control to use something that will compost down. Several layers of cardboard topped by something heavy like 6 or more inches of wood chips has often been suggested. I've heard that a thin layer of cardboard doesn't work on bindweed, because it winds its way between the cracks, so cardboard only works on bindweed if it is several layers thick, with the cracks staggered in different layers.

Nicole Alderman wrote:I was FILTHY after cleaning this area up. I smelled of poopy anaerobic bacteria and was covered in duck poopy, leafy plastic slury. It was definitely time for a shower.

A new Permaculture perfume, Eau De Le Pew?

Sure to attract other Permies, and the odd Blow Fly or two!

It may seem counterintuitive, but building a good wood fire on the polluted area will melt the plastic and make it coalesce into small globs of plastic that would be easier to find when sifting through the ashes. It may take a couple of fires to get it all.

(It's something I've observed during years of bushwalking when using old campfire sites - after we extinguished the fire the next morning and moved the coals around to make sure the fire is out, globs of plastic and foil left behind by others can be separated from the ashes.)

We use plastic to kill weeds and it NEVER turns into small fragments like that, (I think it would eventually but it would need to be 10 years in the sun) that was not UV stabilised plastic. We only use silage plastic which is designed to be out in the sun and has to stay in one piece for the season, it takes a full year to kill our collection of weeds (marestail, creeping thistle, nettles, couch grass, ground elder and bindweed) but it does after 12 months you start with clear soil.

The previous owners of this place buried their rubbish all around in plastic bags, of course these have now turned into exactly the little scraps you describe and so have their contents, while I have a ton of experience picking bits of plastic out of brambles/roses I can't say I've found any good way of doing it.

Oh, please don't burn your soil. Doing as F Agricola suggests would just create dioxins in the soil you're trying to cleanse.

Seriously, I think you're doing as much as is reasonable. What you can't pick with your fingers, maybe you can bribe some smaller fingers to get and turn it into a game, besides.

If you really need to get more, I would try a mesh sieve. Make a few yourself with wooden frames and different grades of mesh. Stack them one atop the other, coarsest at the top, fill with scoopfuls of plasticky soil.

I also had this thought involving a scarf or two of differing static potentials being used to generate a static field that attracts plastic particles out of the soil descending through the sifter. Static cling, do your thing!

Seriously, though, mechanical removal might be tedious, but I think its the only real way, even with mechanical and static cling filters. Apart from that, I think oxygenated compost extracts and fungal slurries are your best bet.

If you don't have bees but know some beekeepers hand-picking wax beetles, maybe get some of those in your contaminated soil. They have been known to eat plastics and styrofoam.

Keep us posted, and good luck.

-CK

wax worms eat plastic

Chris's post prompted me to look this up. This article is about wax moths rather than beetles. Apparently they DO eat plastic. I learn something new every day at permies.

It's probably the wax moth I was thinking of, Mike. Thanks for the link.

-CK

Been digging into this some more. So far have found no documentation of hive beetles eating wax. Found this interesting article about the beetles though. Specifically the nematodes that kill or disrupt the beetle larvae. Going to run it by Dr. Redhawk so as not to derail this thread any further. Hoping it will be a good addition to my bee gardens of oxalic acid bearing plants.

Now .... if I could just train wax moths to find & eat the tiny plastic fragments that resulted from cutting a piece of blue carpet months ago. They seem to reproduce like tiny blue smurfs.

One comment before this thread gets derailed badly...
From Mike Barkley's Wikipedia link above
"Two species of waxworm, Galleria mellonella and Plodia interpunctella have both been observed eating and digesting polyethylene plastic. "  
Plodia interpunctella is Indian Mealmoth. This might explain why they seem to end up in sealed packages in the pantry.

Before it all gets mixed in the soil you could burn it all with a propane weedkiller, reduce it all to ash and then mulch away. Just a thought.

Again, burning is bad. It will disperse the most volatile elements into the surrounding environment, and create situations in which you don't want to grow food.

At that point, better to just leave the plastc bits. Mulch overtop of them to keep them out of the sun, and just don't worry about them.

Better than creating a bunch of dioxins so the soil can be pretty.

-CK

Nicole, instead of hand picking the bits, have you tried a vacuum? Either a shop-vac or one of the leaf vacuums?
The plastic bits are so light, they’ll get sucked in before the dirt and sticks. With a small shop vac you could use the wands and a crevice tool to make a long enough “pole” to do the work while standing/walking around.
You’ll suck a bunch of leaves for sure, but I’d bet the shop-vac would be only 50%, where a leaf vacuum would be less discriminating.

Chris Kott wrote:Again, burning is bad. It will disperse the most volatile elements into the surrounding environment, and create situations in which you don't want to grow food.

At that point, better to just leave the plastc bits. Mulch overtop of them to keep them out of the sun, and just don't worry about them.

Better than creating a bunch of dioxins so the soil can be pretty.

-CK

I stand corrected and I would no longer recommend the burning of plastic. I thought maybe the more volatile elements would be destroyed by burning. Please disregard my above-mentioned idea. I looked up dioxins and indeed they are released by burning. And no amount is insignificant. In retrospect I think that the best option would be to rake it up. Thanks.

Nicole, I had a similar project a few years ago.  There was an abandoned blue plastic tarp in some of the woods where we had had a wood storage area when I was a kid.  So it had been there disintegrating for 20+ years.  Some of it came out in folded chunks but mostly it was lots of little/tiny pieces.  And I didn't want to waste the good soil it was in or leave a big ugly hole so it was a lot of hands/knees work to pick out all of the little pieces.  So satisfying to have that part of the land start really healing though.

A couple years later, I ran into this:  http://airliftseparator.com/

I'm sure it's too expensive for the household projects like yours and mine but it still seems like a pretty handy gadget for larger projects!

Chris Kott wrote:Oh, please don't burn your soil. Doing as F Agricola suggests would just create dioxins in the soil you're trying to cleanse.

Duh! Agreed, didn't think of that!

I've read that PVC will leave dioxins if burnt, but don't know the chemistry of burning/melting polythene - black plastic film. Better to err on the side of caution, eh?

I had to look up Dioxin, having never heard of it before:

Dioxin

di·ox·in
/dīˈäksən/
noun
a highly toxic compound produced as a byproduct in some manufacturing processes, notably herbicide production and paper bleaching. It is a serious and persistent environmental pollutant.

The previous owner of my property used to burn trash. I've found melted plastic and metal bits that he dumped in--what is now--my duck yard (didn't know he dumped burnt trash there before we fenced it in). Now I get to worry about my ducks eating dioxins. Great!

ANother good reason to not burn the area is that there's still a vine or two of bindweed in there...and if I burn everything, the bind weed will have no competition and will have a splendidly easy time taking back over. I sure don't want that!

Kenneth Elwell wrote: Nicole, instead of hand picking the bits, have you tried a vacuum? Either a shop-vac or one of the leaf vacuums?

I'm not sure how well this would work unless I also vacuumed all the salmonberry, etc leaves that are mixed in. And, the season that I can access the patch is also WET, so all the leaves and plastic are wet and heavy.

I went out and got some more pictures today of the area. It's REALLY hard to distinguish the small black plastic from wet leaves. I'd pretty much have to vaccum up and take to the dump all the leaves in the area!

Sonja Draven wrote: Nicole, I had a similar project a few years ago.  There was an abandoned blue plastic tarp in some of the woods where we had had a wood storage area when I was a kid.

I just dealt with this one, too, sadly, though not to as large of a degree. I'd wanted to make a play pit for my kids, and so excavated a bunch of soil/weeds, figuring I could use it to make a garden bed. I put it on a blue tarp thinking I'd get the bed made within a month....instead it wasn't for 8 months...in which the tarp started to break down. LIttle animals tunned through it and roots worked their way through the tarp. It was pretty fragile and prone to ripping and leaving little horrid strands of plastic. Thankfully, I got to the pile before it was all in that state, and was able to scoop off/scape off the soil and then oh-so-very gently lift up the tarp. Doing this, I managed to only have to pick up a pocket full of plastic strands. Never again will I put soil on a tarp like books say to. Even with the best intentions of getting the the soil off the tarp in a week, life might happen and there might not be time to remove the soil for months.

Yes!  Welcome to the PNW - where people ask if the scratches on your arms are from tangling with your cat or blackberries.  ;)

Nicole, the shop-vac wand could poke into places where you wouldn't dare put your arm (especially if you get a few extra sections), and get those all those pieces that always seem to break apart just as you try to grasp them.

It is maddening to have to correct/repair a mistake since it always seems to take longer than it did to make it... and often longer than "the right way" might have taken in the first place.

I wouldn't worry about sucking up leaves along with the plastic... you can get/grow some more to replace them, and be done with it.
(or you could dump out the shop vac onto a table and rescue all the leaves from the plastic bits...please don't...obsess over making faeries instead :-) )