Return to the Soil Forum | Post a Follow-Up

 o
Cover With a Tarp?

Posted by ceresone missouri ozarks (My Page) on
Thu, Jul 31, 08 at 8:38

I just read on another post to cover with a tarp to get your pile really hot to steam-kill weed seeds.
When mine is finished building, do I need to do this to insure seeds are killed? Some seeds will be the hated Bermuda Grass seeds-and I so want them dead!


Follow-Up Postings:

 o
RE: Cover With a Tarp?

I honestly don't think ANYthing on earth can kill bermuda in any form. Scary stuff.

As to covering - it is debated - has pros and cons - but it sure isn't required in any way assuming a well managed pile.

My personal opinion is tarping does more harm than good. While it is trying to steam-kill the weed seeds it is also steam-killing much of the beneficial organizims, nutrients, flora and fauna.

But I linked several previous discussions on the question below just to be politically correct and give the other side equal air time. ;)

Dave

Here is a link that might be useful: Tarp/cover compost discussions..


 o
RE: Cover With a Tarp?

I said that about covering with a tarp, but I was just speculating. We were posting specifically about giving a cold pile a short hot phase with the main purpose being to kill weed seeds. It was not meant as a recommendation for general composting, or really even a recommendation at all. I was just kicking around ideas on the spur of the moment.


 o
RE: Cover With a Tarp?

I know, didnt mean to sound like I was criticising,PetalPatsy, just in reading that post, I got to wondering if it would possibly kill the Bermuda Grass seeds. I'd do about anything that might kill those seeds.
Lots of my lawn has this dratted weed, so in order to use clippings, I have it also.
Perhaps the chicken litter, and horse manure will heat it up--since its so hot this summer, I cant see any steam, and I dont have a thermometer.


 o
RE: Cover With a Tarp?

I'd strongly encourage you to avoid using your own grass clippings then. Strongly!! Find another source of grass clippings. ;)

Dave


 o
RE: Cover With a Tarp?

Covering a compost pile with something impervious such as a tarp or plastic, something that would limit air exchange to the compost, is not a good idea, unless you built a structure over the compost pile that would allow that tarp to keep excess water off the pile while still allowing it to breath. If you limit the amount of air the bacteria that are digesting the material in your compost pile that will slow them down which means not as much heat would be generated which means that cover would be counterproductive.


 o
RE: Cover With a Tarp?

I second what Dave said - don't throw clippings in there if they have Bermuda seeds in them! Do you really want to grow a bumper crop of Bermuda everywhere you spread your compost? If not, don't take the chance - it's not worth it!!

I don't put weeds in there that are going to seed either. For example, I only have a few dandelions, so if any have their fluffy heads before I mow, I go around the yard picking them and putting them in a waste basket. Then I mow. If a crabgrassy area is going to seed, I don't mow that part with the bagger on. Weeds in the garden are a big enough pain without me purposely spreading their seeds around via my compost. Yes, the center of my piles get pretty darn hot, but what about all those weed seeds around the edges? No thanks.

Deanna


 o
RE: Cover With a Tarp?

I put Johnson grass, pulled bermuda and bermuda with seeds in my pile all the time. I've never noticed it causing problems. Of course I make sure it's finished composting.

If your pile isn't getting hot and it has nitrogen and carbon, then it ain't wet enough. Lack of water is the most common reason for cool piles. It takes alot of water to compost.

The only reason I might cover a pile is to keep too much water out of it. And it would have to been raining for a long time for me to do that.


 o
RE: Cover With a Tarp?

Yeah, whatever gets mowed gets composted, Bermuda grass included. Never had a problem with Bermuda grass or dandelions in the compost pile.

Tomatoes are another issue. Throw in those unharvested tomatoes in the autumn and you will have volunteers the following spring. :-)


 o
RE: Cover With a Tarp?

This is quite a problem for me, I mow almost 10 acres, over half is composed of Bermuda. If I dont use grass clippings, then I Cant use all those clippings. How hot do I have to get to ensure the seeds are killed?


 o
RE: Cover With a Tarp?

I compost all my invasive grasses, roots, seedheads and all.

Just because a plant is hated doesn't mean it's not compostable. Hard, dense seeds like those of bindweed, may be an exception, but grass seeds have never been a problem for me. I've also had trouble with stray woods hyacinths, but I think that was from escapees.

Keep in mind that there are two forms of seed destruction going on in a pile; heat kills, but so does regular old rotting. What happens if you plant corn or bean seed too early? It rots because the soil is too cold and moist. The same thing happens in a compost pile, even in a cool one.

Regarding covering with a tarp, that could be a way to cut down on leaching of nutrients from rain, and preventing the sides of a pile from drying out. I had a real problem with hot winds when I composted in Las Vegas. I just can't see a tarp cutting off oxygen to a pile. That's like saying not to use a tarp to prevent hypothermia in a survival situation. You would have to wrap yourself up pretty darn tight to suffocate yourself. Also, if you used one of those blue tarps, they aren't impervious to anything, including moisture. Try lining a shallow hole or a box with one and catching rainwater (or filling with a hose)... it won't stay in it.

Sue


 o
RE: Cover With a Tarp?

Hi all,

Reading this thread brought to mind this question: I am adding hand shredded newspaper to my compost pile. It is layered over the top pretty thick. It is then watered down. Does this constitute a tarp like layer that cuts off air to the pile? Wouldn't any type of layering compost pile have an air circulation problem because of the layering? Mahalo.


 o
RE: Cover With a Tarp?

If you wonder if a tarp, or plastic, will cut off air to a compost pile take a piece of either on large enough to cover your nose and mouth and then try to breath through either one. The same thing happens to your compost pile.
lehua13, whether your paper will do the same thing depends on how thick a layer of paper you put there. Wet paper does tend to clue itself together, like paper mache, and a thick enough layer can stop air infiltration.


 o
RE: Cover With a Tarp?

Ceresone, if you are mowing 10 acres you must have a huge pile and my understanding is that the bigger the pile the more chance it will get hot enough to cook anything! I would think that the tarp/no tarp question would depend upon your particular climate -- you really need some moisture to get the pile working properly. Perhaps you should build a separate pile incorporating the Bermuda clippings and browns so you can see if the seeds cook.


 o
RE: Cover With a Tarp?

Kimmsr said "If you wonder if a tarp, or plastic, will cut off air to a compost pile take a piece of either on large enough to cover your nose and mouth and then try to breath through either one. The same thing happens to your compost pile."

Covering a compost pile with a tarp of any kind is not the same as sealing it in a Ziplock plastic bag. All you're doing is covering it to shunt rain off to the side, or cutting down the amount of surface exposed to the wind. Even if you put a few big rocks around edges to prevent the tarp from blowing away, air will still be getting to the compost.

Extremes of ANYTHING aren't good: too much/not enough rain, sun, wind, nitrogen, potasssium, phosphorus, calcium, lime, magnesium, sulfur, one-a-day vitamins, mashed potatoes, chocolate, politicians, lima beans, hot sauce, spaghetti, bleach, laundry detergent, and a million other things.

One thing that drives me up a wall is the American way of taking everything to extremes. Shooting a rabid skunk is NOT the same as a serial killer shooting 50 people. Watering your garden is NOT the same as blasting a hole in a dam above 350 homes. A BBQ is NOT the same as setting half of southern California on fire.

STOP with the extremes, okay?

Sue (and no, I'm NOT in a good mood today -- what tipped you off?)


 o
RE: Cover With a Tarp?

Since I have, in the past, covered one of my compost piles with a tarp I can speak from experience that the tarp will greatly restrict air flow and you can get an anaerobic digestion process going because of that restricted air flow.
My compost piles, in a wooden bin, are covered so I can better regulate the amount of moisture in those piles, but there is plenty of room around for air infiltration. A tarp, or plastic sheeting, will not allow any air infiltration. I have camped out using tarps for tents and they do not breath.


 o
RE: Cover With a Tarp?

I hope you're in a better mood, belgianpup--and I bet you are if temps are lower for you there like they are here in TN. Because man! I fell out laughing! Nothing like taking extreme examples of going to the extreme to criticize...going to extremes!! Ahem...whew...I guess it just struck my funny bone, gasp, giggle.

Now, boys and girls, kimmsr is...dare I say it, right. A tarp won't seal off a pile from air, of course not. It blocks the pile AIR FLOW, or ventilation --see the post on passive aeration--oxygen doesn't just diffuse into a pile, it's pulled in.

Normally, hot air rises from a pile and creates a vacuum effect at the bases and sides to entrain fresh air. It's kinda like a chimney effect. A tarp that retains that heat messes up the air flow and the hot humid air would collect in the bubble and fill it up, until the oxygen inside the pile was used up and aerobic bacteria died.

I don't know how long it would take for hypoxic death of the aerobic bacteria, or whether the heat would kill weeds seeds better at the edges before the whole cycle collapsed on itself.

My idea, which I was kicking around ONLY, on the spur of the moment, was, since I read on the internet that weed seeds died in only 15-20 minutes at 140 degrees, that slapping a tarp on a hot, hot pile for a mere hour might be enough to more thoroughly kill weed seeds.

NOTE: this was specifically a hot finsh out scenario, the last hurrah of a well mixed addition of UCG and very finely whipped up leaves before the pile was left to mature.

kimmsr has said elsewhere that it's not just the heat that kills weed seeds, but the whole process. BUT, heat has always worked for me, and I'm always looking for 'a better, faster' way to achieve my highly personal compost goals.

Gentlemen, we have the technology. *


*see UCG, OP grass clippings, weed whacker, garbage can, OP fall leaves, water and/or pee/aquarium water, sweat, thermometer, tarp


 o
RE: Cover With a Tarp?

  • Posted by pt03 3 Southern Manitoba (My Page) on
    Sat, Aug 9, 08 at 19:41

 o
RE: Cover With a Tarp?

Pt: Thank you for post that photo. I like the looks of that. And it's inexpensive.


 o
RE: Cover With a Tarp?

pt03--what a lovely, lovely picture. :) Your covering is a lid, still open at the top edge all around as well as open at part of the side. It's not exactly what I was picturing when I said 'cover with a tarp.' I was imagining a bigger tarp over a smaller pile, so that it would be one solid tarp, working as a cloche. Nevertheless, what a great picture, and look at all that rich soil all around! That's what we're all after!


 o Post a Follow-Up

Please Note: Only registered members are able to post messages to this forum.

    If you are a member, please log in.

    If you aren't yet a member, join now!


Return to the Soil Forum

Information about Posting

  • You must be logged in to post a message. Once you are logged in, a posting window will appear at the bottom of the messages. If you are not a member, please register for an account.
  • Posting is a two-step process. Once you have composed your message, you will be taken to the preview page. You will then have a chance to review your post, make changes and upload photos.
  • After posting your message, you may need to refresh the forum page in order to see it.
  • Before posting copyrighted material, please read about Copyright and Fair Use.
  • We have a strict no-advertising policy!
  • If you would like to practice posting or uploading photos, please visit our Test forum.
  • If you need assistance, please Contact Us and we will be happy to help.


Learn more about in-text links on this page here