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For the gardening monkeys....

mantispf2000

Turbo Monkey
Aug 9, 2001
1,737
193
Nevada, 2 hours from Mammoth
A simple question for a change.........

I used grass clippings for fill/mulch/fertilizer for our veggie garden. Wife seems to think the chemicals used last year will still be in the grass this year. I say the chemicals have run their course and the clippings are "clean".

Who's right, and yes, I appreciate that you care..........
 

Montana rider

Monkey
Mar 14, 2005
601
506
It probably depends what type of chemicals you were using, how you compost and how wet/warm your compost piles get...


http://www.extension.umn.edu/distribution/horticulture/components/3296-02.html

Avoid composting plants that have been treated with herbicides or pesticides. Small amounts of herbicide-treated plants (e.g., grass clippings) may be mixed in the pile as long as you are careful to let them decompose thoroughly. Studies have shown that low levels (less than 0.1 parts per million) of 2,4-D, diazinon, and pendimethalin can be detected in well-composted yard trimmings2. This level, however, is less than 1% of the level typically found in yard waste mixtures prior to composting and is not considered a risk for using in the garden. Ideally, clippings from lawns recently treated with herbicides should be left on the lawn to decompose (see section on Alternatives to Composting Grass Clippings). Both pesticides and herbicides are degraded at varying rates. A list of common chemicals used on the home lawn and their degradation rate in soil is provided in Table 1. Even if some treated grass clippings are used, the degradation of these chemicals in a properly maintained compost pile should be at least as fast as that in the soil.




Table 1. Persistence of herbicides in soil 3



Common Name

Trade Names

Persistence in Soil
(months)




--------------------------------------------------------------------------------




Benefin

Balan

4-8



DCPA

Dacthal

4-8



Bensulide

Betasan

6-12



Glyphosate

Roundup, Kleenup

Less than 1



2,4-D

(Many Formulations)

1-2



MCPP

(Many Formulations)

1-3



Dicamba

Banvel

3-12

AND THIS ONE:

http://www.rachelcarsoncouncil.org/index.php?page=killer-compost-new-problems-a-new-chemical

Killer Compost: New Problems, a New Chemical.

We have recently heard reports of continuing incidents of herbicide contaminated compost damaging crops of organic farmers and gardeners. A news report ( http://www.capitalpress.com/SB-herbicide-residue-123110-art ) discusses continuing damage from residues of aminopyralid in composted grasses. The report also discusses labeling changes proposed by Dow AgroSciences to help address this problem.

Additionally, we have learned of another "Killer Compost" chemical herbicide. It is called Aminocyclopyrachlor, and this one does come with a restriction on the label.

As we have previously discussed some herbicide active ingredients including clopyralid, aminiopyralid and others are registered for use on pastures. These chemicals can be so persistent that they remain active in the manure that animals pass after grazing on the treated grasses even after this manure is composted. This can create a major problem for anyone who uses the contaminated compost as it can kill or seriously damage broadleaf crops and garden vegetables.

The Washington State University Extension Service reports that herbicide contaminated compost was responsible for "tens of thousands" of dollars of lost revenue for several organic farms, and additional damage to several home gardeners. Tests confirmed the presence of aminopyralid at low levels. The chemical can cause damage to plants at concentrations as low as ten parts per billion (10ppb).

A spokesman for Dow Agrosciences the maker of aminopyralid said that the company had submitted a proposal to the Environmental Protection Agency to address the handling of the herbicide, and that they would be meeting with the EPA shortly. The suggested changes would make it illegal for people in several states to move aminopyralid treated hay or forage grass off the farm where it was applied. A supplemental label however would exempt users in some states.

Another herbicide active ingredient to be aware of is Aminocyclopyrachlor. This herbicide is of a different chemical family than the other killer compost chemicals that we have warned about before, however it has a similar mode of action and a similar risk of persistence in compost. (It is not registered for pasture use however)

Products containing aminocyclopyrachlor come with the following label restriction:

" Do not use grass clippings from treated areas for mulching or compost, or allow for collection to composting facilities. Grass clippings must either be left on the treated area, or, if allowed by local yard waste regulations, disposed of in the trash. Applicators must give verbal or written notice to property owner/property manager/residents to not use grass clippings from treated turf for mulch or compost." (from the label for Imprelis)

At RCC we remain most concerned about these chemicals. The potential to cause harm to unsuspecting farmers and gardeners is very disturbing. Organic farmers and gardeners rely on compost and should be careful of where they get the compost that they use.

The Washington State University Extension Service recommends farmers or gardeners taking several steps to avoid bringing contaminated compost to their properties.

Ask the supplier for information about the origin of the compost and about who the intermediate handlers were. Ask what farm the compost came from and ask for the details of the herbicide practices of that farm. Establish a contract with the compost supplier to guarantee that the compost is contaminant-free. Perform tests for the presence of herbicide contamination. This can be done by growing a test plant in the compost before it is applied to the entire field. For more information please look at our previous news items on Killer Compost. (LINKS)

http://www.rachelcarsoncouncil.org/index.php?page=updated-information-on-contaminated-compost

http://www.rachelcarsoncouncil.org/index.php?page=a-gardener-alert--update

http://www.rachelcarsoncouncil.org/uploads/articles/AGardenerAlerttoKillerCompost11-5-08.pdf
The Washington State University Extension Service also has information about aminopyralid problems here: http://whatcom.wsu.edu/ag/aminopyralid/



A simple question for a change.........

I used grass clippings for fill/mulch/fertilizer for our veggie garden. Wife seems to think the chemicals used last year will still be in the grass this year. I say the chemicals have run their course and the clippings are "clean".

Who's right, and yes, I appreciate that you care..........
 

buildyourown

Turbo Monkey
Feb 9, 2004
4,837
0
South Seattle
I wouldn't use the clippings on my edibles. I don't grow edibles near the house or street because of historically high lead levels. I bring in new dirt for the beds and don't use any chemicals of any kind. It might seem excessive but ask yourself why you need chemicals.
Grass clippings are lousy compost anyways. Go get some chicken ****.
 

skibunny24

Enthusiastic Receiver of Reputation
Jun 16, 2010
3,279
548
Renton, WA
MR has so much info... tl;dr.

I'd use them. We throw our clippings into our regular compost (we compost everything we can in the house), and I think the process of breaking down in the bins helps. Do you mix them with anything? Do you have a bin where you can let them sit for a bit before you use them? What kind of plants are you using them on?

If you have plants like tomatos or hydrangas that take a more acidic fertilizer, use coffee grounds. Starbucks puts all of their grounds into 5 lb bags and packs them to give away to gardeners for free!
 

stoney

Part of the unwashed, middle-American horde
Jul 26, 2006
15,127
1,818
Colorado
I have used fertilizer on my lawn and am running the clippings in our compost. I won't touch anything with herbicide, but I also dont use herbicide.
 

Pesqueeb

bicycle in airplane hangar
Feb 2, 2007
29,608
5,058
Riding the baggage carousel.
I have used fertilizer on my lawn and am running the clippings in our compost. I won't touch anything with herbicide, but I also dont use herbicide.
I switched to an organic lawn fertilizer this spring for this reason. It seemed like such a waste to be tossing the clippings, they were probably toxic, and I didn't want them anywhere near the veg. I'm doing a lot more weeding by hand this year though. :think:
 

X3pilot

Texans fan - LOL
Aug 13, 2007
5,861
1
SoMD
Probably OK to use in flower gardens and such, but I'd avoid food plots. Personally, we compost kitchen waste and leaves. I use composted horse manure on my yard every year. $150 for 16 cu yards delivered, my yard looks good and smells good when it rains!
 

mantispf2000

Turbo Monkey
Aug 9, 2001
1,737
193
Nevada, 2 hours from Mammoth
See, I'd rather use chicken/house/cow/bat guano myself. Sure it might smell "lovely", yet to results would be well worth the fragrance. Wife's just into re-using poop.

Oh well, since I've already mixed in said grass clippings, guess I'll just have to be typing with my toes in the future.......