Personally I'd avoid applying fresh manure around veggies that are already established and presently growing, the same with "half composed" whatever that means (older but in dry storage?).

Nutrient-wise, the difference between manure tea and manure is that the former is distributed with a bucket and the latter is distributed with a shovel. It's the ammonia in manure that can burn roots, but in lower concentrations, that ammonia makes nitrogen fertilizer. So you can apply diluted manure tea, or you can just apply less manure. Of course, the advantage with manure is that it conditions the soil and makes it more friable. Tea doesn't do that. That's why composted manure (in which most of the ammonia is dispersed) is optimal. You can apply lots of that.

Strongly smelling manure is manure with more ammonia.

So if I premix my manure (either neatish or semi rotted) with a bit of soil,I now feel that it would be unlikely to soak the roots in ammonia to any serious degree of concentration.

I have quite a few areas in the field where the donkeys leave their droppings and now I see a way to use them without having to necessarily add them first to the compost heap (which is actually a mixture of bedding and donkey manure that I generally leave over winter until the spring and summer)

It is not suggested to use uncomposted or unaged manure in an actively growing vegetable garden or around edible plants. In addition to nutrient concentrations (primarily urea) being excessive, there is a very real risk of pathogens contaminating the plants. Salmonella, E.coli and Leptospira are all common to livestock manures. You can apply fresh manure to any fallow planting area now and it should be adequately aged for spring planting.

Why not use the manure from the "compost heap". Dig under the pile to get the oldest.

The pathogen risk is one to take seriously, but then again, even composted manure is often not composed completely, and some will remain. That's what you get with casual composting, without proper mixing and heating. Salmonella and E. coli easily survive in a dry environment for example, so just leaving it in a not-so-hot pile over the winter won't help much with pathogens, though it will eliminate most of the ammonia. Using manure of any kind presents such risks at some level. Of course, you're always going to get birds and wildlife pooping in your bed. Yes, using a small amount of uncomposted manure can avoid ammonia poisoning, but it's pretty hard to be quantitative about it. Premixing with soil certainly doesn't remove the ammonia. It just dilutes it.

One year I planted two crops of corn in the same spot and after seeding the 2nd crop I spread a couple inches of fresh horse manure because I couldn't find any composted manure that time of year. The seeds germinated and the corn grew well. But that's corn which needs a lot of fertilizer.

But when it comes to in ground crops or low growing crops like lettuce and spinach I would never use fresh or composted manure. I dig in composted manure in the fall and then plant in spring.

To answer your questions: I wouldn't add more manure to your brassicas now. I never add more manure during a growing season as manure is a slow release fertilizer and will provide all the nutrients you need for the current growing season and even for next season for many crops. I would collect the manure in the field and pile it up and let it compost better. But if I were digging a new garden and needed a soil amendment I would dig in the fresh manure now and would be comfortable next spring.

Also I don't think you can add too much well composted manure. My previous test was adding too much and getting 14 foot tall beefsteak tomato plants, but they gave me the usual amount of tomatoes, maybe more for the Yellow Pear tomatoes. Last spring I built a hot frame with a foot of manure a foot down under the soil. The tomato plants that I didn't set out just grew and obviously got down into the foot of fresh horse manure. The plants grew very long but looked healthy. There were a lot fewer tomatoes, but that was partially because of a lack of sunlight in that jumble of plants.

How do you know when you added too much ammonia? The plants will die. 75 μg/m3 is supposed to be too much but, yeah, that's not that helpful. Also, worth knowing that different plants have different degrees of nitrogen toxicity. Solanaceae (eggplants, peppers, and tomatoes) are especially sensitive. As I said, it's pretty hard to be quantitative about it which is why most home gardeners don't do it. Actually, farmers DO add ammonia to their fields, but they do so in a careful, measured way. I think one tablespoon of pure household ammonia per gallon of water is safe fertilizer. But that smells a LOT less than fresh manure, so fresh manure is a lot more concentrated.

BTW, well composted manure is free of most ammonia and pathogens. Old, aged, or simply "rotted" manure still has pathogens, but if it was kept moist, the ammonia has largely departed.

I should add that, at least with regard to nitrogen, manure is a fast release fertilizer. The ammonium nitrates are right there. For everything else, yes, it is a slow release fertilizer, as is most vegetative compost.

So what doesn't kill them feeds them? ;-)

I can pile on the manure up to the point they kee over and peg it?

Not some mid way dosage where more harm is being done than good?

Yep, ammonia turns into a fertilizer. But before it does, it's a poison. The issue is how much is too much. Different manures at different stages of aging will have different concentrations of ammonia, so it isn't simple to say how many shovelfuls are deadly. Chicken manure has the most, cattle the least. So yes, if the ammonia doesn't kill the plants, the ammonium cation that it eventually leads to in the soil will help the plants grow.

It's a BIG DEAL for farmers what the ammonia volatization rate is. That's how much ammonia floats away instead of getting converted into ammonium. That's what farmers worry about when they dig fresh manure into the soil, well before planting. Now, if you want to put manure on plants, you want that volatization to be pretty complete. Of course, that means that the amount of nitrogen fertilizer that you get from it will be a lot less. That means that the best way to use fresh manure is to dig it in immediately, and let it convert to fertilizer BEFORE PLANTING.

I'm guessing that if the manure is kept moist, and well chopped up, after a month or two it should be pretty clean of ammonia.

Thanks (chemistry was one of my very weakest subjects :-) )

One thing I'd note is the strong ammonia smell from some manures is often mainly from urine, particularly if the manure is collected in a slurry. Field manure including from donkeys probably won't have this issue, or not as much. Also, I think donkeys, like horses, are non-ruminants and hence the fibre content of the grasses they eat is much less broken down (less, er, dense) - more air and bulk structure in their final product.

That said, I'd echo the main concern is pathogens if this is to be applied around food crops - in a word, just not worth it. For non-food plants in a garden, if you get it a bit wrong with overly fresh manure, you've just lost some plants.

FWIW, I read that donkey manure (like horse manure) has somewhat lower nitrogen content than other manures. That's ammonia. It's also pretty dry, which isn't a good way to volatilize the urea that makes it.

• Do the pathogens that have been mentioned need to be in contact with the edible parts of the plant to present a danger or can they also travel through its system?

Good question. With regard to salmonella, the answer is that yes, root uptake definitely happens. For example

https://www.foodsafetynews.com/2019/01/researchers-uncover-how-salmonella-infects-plants-before-harvest/

With regard to E. coli, not so clear.

https://www.foodsafetynews.com/2011/04/researchers-unlock-an-e-coli-mystery/

But splashing of pathogens onto fruits and leaves by rain is always possible.

Again, the issue is avoiding LOTS of these pathogens. Salmonella and E. coli are always present in the environment. They are toxic when you consume too much of them.

I seem to notice from your first link that there may be no danger from these pathogens if the vegetable is to be cooked.(from the salmonella at least)

The danger seems to be more so when growing lettuce,tomatoes etc

So brassicas seem to me to be quite safe unless possibly if the leaves are eaten raw in large enough amounts (which we do as it happens)

170F for 10 minutes or 130F for an hour will do it.

I'm guessing that most of the pathogen is just splashed or wind-blown onto the surface. So a good washing is most important.

Now, keep in mind that if this stuff is airborne from, for example, manure that is dried and dusty, you'll get a dose of pathogen just by breathing it as you're shoveling it. Of course, these pathogens are shed by animals in other ways, like saliva. If you're around infected animals, the bacteria are all around you. As normal environmental constituents, these pathogens are naturally dealt with by the immune system, up to a point.

Let's face it. Playing with uncomposted manure isn't all that safe.

Personally I would NOT rely on cooking vegetables to deal with all pathogens, except for the types of vegetables you know must be boiled or at very high temperatures for specific periods (like a rutabaga or something like that) or in soups/stews. Why? Because we (for example) like to prepare our vegetables very lightly steamed and by most standards under-cooked, crispy. No way I want to keep track of which vegetables were treated with the manure.

(And yes, I'm aware that we are taking some risk with veggies and that they're not going to be pathogen 'free.' That's the way we like our veggies is all).

Manure tea needs to be aerated while steeping to avoid anaerobic organisms from proliferating.

I will just add that, to the extent you want to use this manure as a *mulch*, and not dig it in, such that it is not contacting the roots directly, you probably won't kill the plants as long as the manure doesn't have an ammonia smell. Just sniff carefully, assuming it's moist. If it's dried out, the urea could have crystallized, and may release a lot of ammonia when moistened. Of course, if used as mulch, then it's just laying on the surface, drying out and blowing around onto the veggies, which is pretty much inviting contamination.

"Drying out" would be a cruel irony in our part of the world ;-)

Of course, if your part of the world isn't dry, mulching may be unnecessary.

I prefer chicken manure.

If the barn your manure came from has an earthen floor then there will be very little ammonia as they won't use straw, wood chips etc as there's no need for any bedding. The urine will soak into the ground.

Also; never use manure with wood chips used for bedding. The wood chips will prevent direct seeded seeds from germinating and you'll blame it on the manure.

Not sure I believe that. The moisture in manure is basically urine, and the urea in urine will decompose into ammonia. I don't think you're going to find any fresh, moist manure that won't produce a lot of ammonia. If you dry the manure, the urea will crystallize and be ready to produce ammonia when it is moistened. Now, it's true that if you rinse the manure with water, the urea will leach out, leaving you with urea-less manure, which is nutritionally pretty poor.

You need to think of the plumbing on the animal and what's on the floor of the stalls. If you have a concrete floor you get a puddle; so bedding is used to soak the puddle off the floor. If you have a dirt floor the urine will soak into the earth so no bedding is used. In that case the only other organic matter in the manure will be some spoiled hay that the animal knocked to the floor. My cows wouldn't eat the hay off the floor unless it was in a corner where it didn't get spoiled.

Your "Now it's true" comment ignores the fact that probably 99.9% of manure is stored out in the rain.

Well, with fresh, moist manure the urine hasn't yet soaked out into the earth. Even later on, only a small amount will have soaked out. If you leave a wet towel on the ground, it won't dry out because all the water soaks into the earth. By the same token, fresh moist manure probably hasn't been rained on much. Once the manure surface has dried into a crust, not really that clear to what extent rainwater will effectively leach what is inside. True, that if you want to leach urea out of manure, it ought to be soft and permeable.

Your still ignoring the plumbing. And I don't want to Leach My Manure. I use it as a fertilizer / soil amendment.

This is a gardening forum. I've spent some time loading manure at a barn. Sometimes in spring it gets crowded and conversations develop. I've never heard a discussion of how great the ammonia is in this pile; or isn't.

Seems like on every discussion about manure there are a couple folks who drag the conversation into their chemistry text books from 40 years ago. If your not getting paid by the bagged fertilizer industry; you should be.

"Seems like on every discussion about manure there are a couple folks who drag the conversation into their chemistry text books from 40 years ago."

And for a very good reason. Do you think that somehow the "science" of manure has changed in the past 40 years? Aside from being more aware of the dangers involved in using fresh manure, it hasn't!!

Science !!! It appears that some "scientists" can't understand the purpose of the bedding in a stall. For hundreds, thousands of years of years simple folk have known, Remember the manger scene. And NOT only that; they knew how to use it while growing crops.

But! A bigger question! How does one imagine that all the urine in a stall winds up in one clod on the earth floor. Lets hear a scientific explanation for that one.

one has to know the basics of a subject before he/she can take their thinking into the scientific realm It's so obvious that those who dispel the manure conspiracy have never used it; never hauled it. Never marveled at what nice crops it grows. And then you're the one who promotes the use of human manure but has a problem with animal manures.

As I said many days ago, ammonia volatilization in a manure pile is a big deal for farmers. You can look it up, and I'll leave it at that. https://lmgtfy.app/?q=ammonia+volatilization. Oh, that's not 40 year old textbook stuff. But it does involve a little science, which seems to scare you.

That being said, I've shoveled manure and bedding in stalls, and I also understand something about urea. Kind of odd being accused of promoting the use of human manure. I have NEVER promoted that, or even asked about it. I also don't have any problem with animal manure, as long is it is used safely. Several years ago, I posted some questions about using urine for fertilization, and that was pretty interesting. It's not that simple.

How does one imagine that all the urine in a stall winds up in one clod on the earth floor? Beats me! I never thought it did. Manure conspiracy?

dan, John may be referring to me re: the human manure, although I only remarked on it......never advocated its usage (although it is quite common in some parts of the globe).

And I too would be interested in knowing more about this "manure conspiracy" :-) Was not aware there was one........... But the "conspiracies" DO tend to exist for those who are not well informed or hold unsupported opinions.

I'm going to repeat what my recent post contained which became an attack on science:

"If the barn your manure came from has an earthen floor then there will be very little ammonia as they won't use straw, wood chips etc as there's no need for any bedding. The urine will soak into the ground.

Also; never use manure with wood chips used for bedding. The wood chips will prevent direct seeded seeds from germinating and you'll blame it on the manure."

I also referred to those who take a garden thread and copy into it many posts that are so scientific as to scare away the folks who were posting there.. I was referring to making a garden thread a boring textbook. But you can't comprehend something so simple. My point is you don't need a degree to understand the benefits to gardening that manure can make.

I tried not to get vulgar referring to how the urine does or doesn't get into the manure when it soaks into the ground. Trying another vulgarless try. If there's no straw for it to soak into, when the stalls cleaned up. how does the urine get into the wheelbarrow and then the manure pile.

I want you to reread what I reposted above. What is wrong with the post. Will the vast majority of the urine soak into the ground in the stall. Or will it mostly soak into the clod. If it soaks into the ground how does it get to the manure pile. And think about this: why would we use bedding in a stall with a dirt floor. Are you saying that all that straw we used for thousands of years wasn't necessary. The clod will soak it all up without the bedding..