Fresh manure, as opposed to composed manure, is much higher in nitrogen and micronutrients and has an acidic pH, as opposed to compost which has a neutral ph. The amount of N difference depends on the source of the manure.

However fresh manure is not recommended for use around food crops. Only composted manure (90-120 days) is recommended in food production because of the bacteria and other pathogens it can contain.

You can find more detailed discussions about manure, its uses and benefits, over on the Soil & Composting forum if interested.

Dave

Compost and manure are both decay products of a process that is bacteria-dominated. The main difference are two: there are potentially dangerous bacteria in manure, and manure is more fertile because it will also contain urine. In fact most of the fertilization (the nitrogen) comes from urine. Manure will also feed the earthworms a lot better, though any sort of unfinished nitrogen-rich compost will do the same, basically producing a better soil through biological activity.

Finished compost is safe, and is a great seeding medium. I plant everything in compost pots indoors or compost rows outdoors, but it really does not count as fertilizer.

I'm glad you asked this, because this is one my biggest questions planning stuff for this season. Last year I considered using horse manure, because a local stable advertised it for free on craigslist. And lots of people swear by it, saying it produces the best tasting veges. But I was worried about pathogens. It was really old manure, so it was probably fully composted, and perfectly safe. But I'm a bit paranoid about these things:) And then there's all the de-worming stuff they give horses. And the last thing I want to do is kill off my earthworms. But I think that stuff breaks down after a while, so it's probably not a big deal with old manure.

So I'm wondering if cut up weeds and weed teas will work just as well. Or if there's something special about it, like you asked, after it comes out the back end of a horse. Urine sounds kinda yucky, but it's typically sterile, from what I've read. At least human urine, unless you're sick. And doesn't require the expense of loading it in a truck, and hauling it. So I'm wondering if a combination of weeds, weed teas, and urine, would work just as well.

Maybe some of the bacteria from the horse remains in the manure, and enhances the soil's ability to continue breaking stuff down, making it available to the plants? Maybe that's why manure works so well? I'm thinking that plants evolved in an environment fertilized by animals, so they probably adapted to it. If that's the case, then finding a way to add the bacteria might help. Or maybe it's something else, like digestive enzymes?

Although it is difficult to generalize about manure (there are so many of them), manures will in general be the refuse of a nitrogen-rich diet. Other minerals, too, abound in greenery and seeds, and are relatively scarce in woody tissue.

So you will generally get more minerals per pound in manure than in yard waste. There may be something else too, vitamins B for example are abundant in manure and are said to help plants. Finally, because the composting of manure is already advanced, manure will release most of its nutrients this year.

Bacteria in the manure may help, as you say, because vegetables generally prefer soils that are rich in bacteria than soils rich in fungi. Nitrogen fixing is a probable leading cause, but there may be other effects as you say.
With manure you have bacteria and bacteria food in one package. If you want the bacteria but are leery of manure why not bury kitchen scraps? They will produce bacteria like no tomorrow.

Health concerns aside, uncomposted manure can give your garden a healthy dose of weed seeds.

glib - Thanks, that helps. And could the kitchen scraps be from a vegetarian kitchen? I'm wondering if weeds left soaking in water would produce the same thing. They smell horrible enough. Or would aerated compost tea do the same thing?

nc-crn - I've got plenty of those:)

Undecomposed manure can be very high in nitrogen, and the undecomposed bedding mixed in can salt you with weeds. Also, whether fresh or decomposed, manure contains a higher level of salt. Heavy use of manure can lead to rising salt levels in your soil if it doesn't get "rinsed" out periodically with excess water and drainage.

I'm not suggesting you avoid manure, but applying 3 inches of composted manure year after year can lead to problems--it did for me. I stopped using manure for a couple years and had to irrigate heavily a couple times to get things back to normal, now I use it with more moderation and use yard waste and other non-salty vegetable matter.

Manure is high in phosphorous. As pointed out above, most of the nitrogen and potassium is in the urine. If your lucky, you can get manure with a lot of urine mixed in. The source of the manure and what they are feeding is important. I work fresh organic manure / urine directly into the soil, because the 90-120 day pathogen counter only applies to when you harvest, not planting. I only worry about pathogens if antibiotics were used or the manure is from a monogastric. I work in lots of other residue and the nitrogen in the urine speeds decomposition. I do not worry about weed seeds. I mulch and use a wheel hoe / weazel. Weed seeds are going to blow in no matter what I do.

Here is a link that might be useful: Building up Soil

I think manure is amazing. I always add a table spoon or two to my morning coffee. Much better than compost to my taste as compost is often bland and woody tasting. While composted manure has that acidic bite that I crave with my morning cup.lol

because the 90-120 day pathogen counter only applies to when you harvest, not planting. I only worry about pathogens if antibiotics were used or the manure is from a monogastric.

Unfortunately most of the university research into using manure in food gardening would disagree with you. UC Davis (for one) has extensive publications on the subject if interested. And their research shows that many harmful pathogens can survive beyond the 120 day time frame. Again, this is all discussed in great detail over on the Soil, Mulch, and Composting forum here.

I will say that it "might" be true IF you only spot applied the manure rather than applying it to the garden as a whole and only planted long DTM crops in those spots. OR if you only harvested anything after 120 days. But that would mean many of your crops would have gone to seed, would be beyond the edible stage.

Since many food crops are harvested at anywhere from 30 to 180 days after planting, the standard recommendation is to avoid using fresh manure around food crops (also helps you avoid the N burning of seedlings that can result). OR only apply fresh uncomposted manures no later than 60 days prior to planting.

The best way to avoid any problems is to restrict your use to composted manures only. ;) That way you get all the benefits of using it while minimizing any risks.

Dave

Investigate your local county fairgrounds. They usually offer composted (old) manure for free if you haul away, the one I'm closest to will even load it. I have a friend with a dump truck and he brings me a load every spring.

Having been raised on a farm and now having retired back to it, I'm amused by the discussion about fresh vs composted. Anyone who tries to use fresh will immediately discover an aroma that ain't rosebuds!! Ignoring health issues, which you certainly shouldn't, this very pervasive aroma will be around for awhile, and if you're in urban setting....

When we actually farmed here, in the spring we cleaned out the barns, spread the fresh cow manure on fields that were going to be plowed under and that was it.

One thing I do wonder about, the "composted" variety which I get and is probably what most of you refer to, isn't composted, it's just old. Composting as I practice it, means periodically turning and aerating the bins. this stuff is just piled and allowed to mellow.

Ev

I raise chickens, so I use chicken manure. Generally, I spread my manure in the fall after I put the garden to bed for the year.

It helps knowing without a shadow of doubt that my animals are healthy.

Dave - your right. Anyone can go to the USDA web site and see the organic certification requirements. They openly and freely admit that harmful pathogens might live beyond the 120 day limit. The decision was made that the chances after 120 days are very slim and not worth requiring. I am very careful about my source and I always work manure and organic matter in by December. That means I can eat raw by April. I have no crops I want to eat raw until about that time. If I did I would work the manure in sooner. Bin composting is far more work than is necessary for the types of crops I want to grow (turnip, kale, okra, collards, etc.). Safety is important, but I would not want people working harder to decompose their organic matter than they need to. Gardening is hard enough as it is. Now if someone cannot get manure in by December, I recommend skipping it or bin composting.

One time a buddy of mine who ate alot of tomato's had to relieve himself and dropped off a pile of number two behind a tree at a jobsite we were working. The next month he went back there and found a tomato plant growing at the same location. I guess manure is good for growing plants.

shoontok you are hilarious whether you intended it or not. That reminds me of a guy's story about the pea that he fed his chicken, and when the chicken relieve itself a few weeks later a pea grew at the exact same spot of the chicken manure. Good to go, fresh manure.