Sadly, you cannot rule out herbicide damage. Depending on the source of the manure, it may contain traces of herbicide in it.

Hay and other feed for horses may be treated with a wide variety of herbicides that may persist through composting. There are a few other threads on the same topic.

Since the common link between the plants is the manure and the plants are showing clear signs of herbicide damage, I would draw the conclusion that the manure is contaminated.

If I were you, I would not use anymore until you could get it tested.

That would have been my first guess too - herbicides in the manure unless you really know the source and can eliminate that possibility absolutely? I've seen it happen several times.

Dave

Well, I wouldn't exactly say that I'm VERY familiar with the source, but I can tell you quite a bit. I met the ladies that own these horses and did shoveling myself.

These horses live in a rented field. The field was unfenced and unkempt until the last two years or so when it was fenced off by the horse owners. As part of the deal for renting, they had to fence it off themselves. The horses roam this field, grazing for the most part, but are fed pellets daily. I find it odd that someone would spray herbicide on an unkempt field occupied with horses. The land owner certainly wouldn't waste money to do it. The ladies that owned the horses would have neither the reason nor the cash to do it themselves.

I've been over it in my head and the only possible source I can think of for herbicide would be if the land owner sprayed the fence-line with roundup or something to keep weeds from growing under the fence. But again, why would he do that when the horses would gladly do it for him? And I don't think horse feed pellets contain any herbicide.

What about the hay?

It was said: "he only possible source I can think of for herbicide would be if the land owner sprayed the fence-line with roundup or something to keep weeds from growing under the fence."

Not necessarily so.

First, roundup shows different symptoms.

This looks more like 2,4-D damage
Or damage from several commercial weed killers that produce the same effect. They're used to get rid of broadleaved weeds among grasses -- in other words, used on pastures, and the like. Passes thru the animals intact, doesn't damage the animals but will damage broadleaved plants in the garden.

You can test your organic matter that you added with a simple bio-assay to determine if the organic matter is the culprit.

Review info, including bio-assay, here:
http://www.puyallup.wsu.edu/soilmgmt/Clopyralid.htm
Same damage, same bio-assay for aminopyralid and other I don't recall right now.

Here is a link that might be useful: inadvertent herbicide damage in gardens; bio-assay

Agree with Jean that it is much more 2-4D looking and if this is a rural pasture then the county likely sprays the easements along road sides with it like they do here. Drift into the pasture is common. Not to mention the horses browsing through the fence.

Herbicide drift is far-reaching. Even a 1/4 mile away pasture spray can drift and don't ask me how I learned this. :(

But the real problem is what to do now with those plants - pull em' IMO - and how to plant new ones in that area. What do you plan to do?

Dave

After hitting "Preview", I realized this post is LONG! Before you guys read enough to judge my intelligence and stop, I would like to thank all those that offered advice on this issue. Even if I don't quite show it, please don't think I don't value the experience I see here.

In researching 2-4D, I found that it had a halflife of 10 days. I picked up the manure on Jan 31. Some of it was aged, some, not so much. Although the age is irrelevant as the manure may have become exposed to the herbicide after being... well, abandoned by the horse. Either way, whatever the concentration, it should have been at half strength on Feb 10, quarter strength on Feb 20, 1/8 strength on Mar 2, and 1/16 on Mar 12. Plants were planted on March 6. In looking at the docs provided by Jean, my plants appear to be much worse than the worst case scenario provided by the studies they did.

However, with that said, it may not be 2-4D either, but something else that is more persistent. Or, there is the possibility that my neighbor sprayed something that I'm not aware of, possibly in his front yard (these are on the end of the bed closest to the front of the house...). Still, I would think that if this were drift, it would have affected more than just these four plants and the difference between plants four and 5 wouldn't be so evident.

Either way, if it was the manure, and I believe we all agree that it is, I may still be OK. I don't care about these plants. There is nothing I can do about them anyway. Even if I were to pull them, I would have to put something else in their place and unless I dig out that whole end of the yard, I'd be putting new plants in the same position as the ones I'd be pulling. Besides, I'm in Texas. It's too late to be setting out. I've never put anything out this late and had it produce anything. The plants are going to have to die, grow out of it, or sit there and pout in a permanent prepubescent state.

I had plants that had this issue last year on the other end of the same bed. They grew out of it just fine and ended up producing as well as anything else in my garden (it was not a good year). In the mean time, I'll keep soaking these plants to see if I can dilute down whatever is in the soil to levels were they are not longer an issue. If the plants die, the plants die. I have about 21 more. Like I said, these are experimentals anyway.

Finally, I agree that this looks exactly like herbicide damage, and if you guys have not heard of anything other than herbicide that could cause this problem from horse manure, then we'll agree that this is herbicide damage.

The main thing I was worried about was my compost pile. I used half the manure I retrieved that day on the spots these plants are now mixed the other half into my compost pile. The compost is about a year's worth and is finally finished. I used all I could this year and thought some manure and leaves now and coffee grounds through the year might keep it young and vibrant to be used for next year. While I'm sure it will be safe when next year's plants hit it in Feb-March of next year, I'll be sure to add some more materials to dilute any herbicide residuals that may persist. I was very worried that I was going to lose my compost pile (how sad is that?) The plants took 3 months to grow. I work on my compost piles year round!

Did you read about the clopyralid? (It can last a year even if composted.)

And do the bio-assay to know for certain if the Organic matter is contaminated or if it was drift.

"In researching 2-4D, I found that it had a halflife of 10 days."

Clopyralid is broken down by incorporating into the soil and being broken down by soil microorganisms. When contaminated material is not thoroughly mixed with the soil (as would be the case in a compost pile), almost no breakdown occurs. It can easily persist in compost piles for a year or even two.

The other thing to remember is that even if it is mixed with the soil and breaks down very quickly ("quickly" being a relative term here), the toxicity to tomatoes is very acute. According to a report published by the Ohio State Extension "It (Clopyralid) can stunt tomato, clover, lettuce, pea,lentil, sunflower, pepper, and bean plants at levels in compost as low as 10 parts per billion..."

If we were to play devil's advocate and say "There is definitly no herbicide residue in the manure", then there is only one other possibility to make leaves look like that, and that would be a virus, but the chance of that is remote at best.

We're sort of getting into Occam's Razor territory here...

Which of these scenarios requires the least assumptions:
A.) Four plants were planted into contaminated manure.
B.) Four plants were selectively infected by a rare tomato virus, while others are left unaffected.
C.) Four plants were contaminated by herbicide drift, while adjacent plants received no drift.

I'm going with "A".

Thanx, Jean. I have some extra sugar snap pea seeds that I'll use for the test. I'll fill a 4" pot with my compost and another in MG (as a control plant) and see if I can see any signs of herbicide damage.

Regardless of the results, there's nothing I can do for these four plants, but at least it will help me judge if I want to use this compost next year. Right now, I was going to take what I have left and mixing it in with my other compost bin that is full of leaves and grass clippings. Maybe I'll hold off on that until I get the results of this test. If I see damage, I will wait and rerun the test again at the end of the year before using it next year.

Great idea!

I have the same problem from adding too much horse manure and am now trying to determine the best course of action based upon soil test results from the local county extension office.
Tested for nutrients, organic matter and soluble salts, and my soluble salts were 1.75 mmhos which is high and all the other tests indicated everything was fine. Herbicide tests are $100 so i will wait. Horticulturist though too much manure raised the salt and thus leach with lots of water and or gypsum to lower salts.

If it is herbicide carry over, from what i have read all you can do is give it time to dissipate and or add soil to dilute and advance the dissipation.

I plan to use 4 inch pots of soil from the garden, fresh manure, aged manure, etc. to try to see which source stunts the plants and if my dilution amendments have worked.

What did you find cured your problem?

It may be hard to determine truth based on 6 plants. When I looked at your pictures, I smiled looking at the quality of the topsoil. If it is the horse manure, then I must be getting lucky on mine. I do not have the knowledge or experience YET, but why not hit those short, slow to grow plants with a heavy dose of nitrogen. What do you have to lose?(late thought by a season or so)

Take care,
Travis

The horticulturist is correct, with the idea of leaching. Thing is, with the water these days, it seems difficult to leach properly unless it comes from the sky. So maybe, we can come to a more probable scenario that when we plant seed,even seed from the same package,that they are not all born equal? I have scene this before,and recently.

BTW, garedneck, I think you think like I think regarding a problem/issue. No question can top the first hand.

Take care,
Travis

I had 2,4d damage that looked exactly like that last year
(overspray from a neighbor). In researching herbicide
damage to tomato plants (they're EXTREMELY sensitive to
herbicide, I found info about aminopyralid as well as
clopyralid. These are considered "grazable" herbicides
that are sometimes used on hay and straw. These persist in
the soil (they pass through the horse)much longer than
2,4d. I have two horses and have always used their manure
on my garden with great success. Since reading this
material, I've stopped using it in the garden since I've
started to use hay cubes from Canada and hay from western
states instead of local hay. I think before I'd use compost made with hay or straw, I'd plant some extra tomato
seedlings in it to make sure they did not exhibit leaf curling. I've also read just soaking the hay (if you have it) and watering an extra seedling with it will cause the
same curl if contaminated. Beans are extremely sensitive to the same so your "pea" test should work. I found out that these chemicals are also used on pastures to kill buttercup which isn't affected by 2,4d (buttercup is irritating to horses)as well as other weeds. Here's some sites you can look at for more info:

http://whatcom.wsu.edu/ag/aminopyralid
http://www.the-compost-gardener.com/picloram.html
http://en.wikipedia.org/wiki/aminopyralid

At another popular forum which begins with T, you'll
find a great deal of info if you use the search feature
for these chemicals or just "herbicide". This forum won't
accept the name of another.