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Timothy Hay and Clopyralid

GA, GA(Zone 7b)


I have a rabbit so there is old timothy hay to dispose of so I was googling "composting timothy hay" when I ran across an article that mentioned the contamination potential of the herbacide Clopyralid into compost. It can survive over two years in compost and harm/kill your plants.

Is clopyralid still used to contol weeds in timothy hay?

I want to compost the hay and use the rabbit manure for my veggie garden but not if it will contain active herbacide. I keep googling and can't find any current information.

Thanks for any help!

Tacoma, WA(Zone 8b)

Hi Danita, that is a very good question. We had a problem with our "zoo doo" in that hay produced in Eastern, WA has the same problem and they could not give out the zoo doo because it was contaiminated. I would contact the supplier of Timothy Hay directly. Is timothy hay a type of hay or a name by a company? I looked on Amazon and it appears a Timothy Hay product is made by "Sun Seed Company"

Sun Seed Company, Inc. . P.O. Box 33 . Bowling Green, OH 43402 . USA . Tel: 419-832-1641 . Fax: 419-832-0724

But I do not know if this is the company that supplies your hay in particular.

Dublin, CA(Zone 9a)

I would call whoever is supplying your hay--I imagine there are multiple ways to grow it and multiple types of pesticides that could be used while growing it so different growers are going to do it differently. It's possible that the company that makes yours gets bunches of hay from a lot of random sources and would have no idea what was used with it though. If that's the case then I'd look around for a supplier that knows where the hay came from if you want to be safe--I wonder if there are even companies that would supply organically grown hay?

Bloomington, IN(Zone 6a)

I believe this herbicide (Dow) has been removed from the consumer market in many states but may still be in many herbicides marketed to the agricultural industry. It has a very lengthy residual effect and can indeed cause damage to food crops. This has been documented and is not an environmental scare story. I purchase straw from time to time for my garden beds and I have started asking this question of all growers that I am considering purchasing from.

Central Valley, CA(Zone 9a)

I just read this thread after I put a bunch of my chicken's manure and timothy hay bedding into my garden. It seems that this herbicide is part of a class of herbicides that are widely used on vegetable crops, lawns and pasture. It can be taken up my animals and passed through their urine and manure. So, even if you avoid this bedding, clopyralid can contaminate your soil through many other sources. Supposedly, alfalfa is the least likely to have this herbicide.

The effects of this class of herbicides is low crop production. Sogns are curled leaves, mis-shapen fruit and twisted branches. Very low levels can effect most fruits and vegetables. It does appear to break down as little as 30 days in some situations. Sunlight rapidly breaks it down.

It supposedly not used that often and only a few locations in the US.

Here are few links I found:

You can also test to see if your compost is contaminated by growing tomatoes,legumes or other sensitive plants in the compost.

Central Valley, CA(Zone 9a)

KayTee called me back yesterday about the use of clopyralid in their timothy hay. The lady said the only info she could get is that they use as litlle herbicides as possible. This worries me because a) they did not know how their product was grown in the first place and b) all this secrecy behind the production of hay. She tried to assure me that her family had grown hay for years and herbicides are for the most part not needed. From looking at different extension sights, it seems that most areas don't use clopyralid if 2/2-D herbicide is available. This other herbicide breaks down quickly and shouldn't be a problem in compost.

I am currently doing a bio-assey test on the areas were I dug in the bedding and my compost. So far, there doesn't seem to be any problems.

Central Valley, CA(Zone 9a)

Its been a month since the garden was planted and 6-8 weeks since it was amended with compost that contained timothy hay.

The cucumbers and about a 1/4 of the tomatoes seem to demonstrate the signs of clopyralid. A few of their leaves are cupped/wrinkled. Some of the very young tomato seedlings have yellow leaves and slow growth. This is most likely fertilizer burn due to heavy amounts of fresh coffee grounds falling on the leaves. The marigolds, lettuce, carrots, basil and green onions seem uneffected.

Despite the appearance, the plants are thriving. The cucumbers have the first signs of buds.

So far, any clopyralid contamination is shown in the general appearance of the plant. Growth and development does not seem to have decreased at all. Quite the opposite, this years garden is more vigorous than previous years. This probably due to the large application of homemade compost.

This message was edited Apr 20, 2010 1:41 PM

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