I live near a horse ranch and the owner has offered to give me all of the horse manure that I can haul away. These horses are fed mostly oats and the pile of this stuff looks like a small mountain. Problem is that I don’t know how to figure out the Nitrogen content of this stuff or if I should even use it.
A friend of mine uses cow manure, but he is very cautious as to how much he uses. About a one-inch layer he says, and his trees look great.
Should I even mess with this stuff? Any guidelines available?
Thanks Karl

I use the Black cow brand from Home Depot. I use one fourty pound bag per tree each spring. The rest of the year they get Vigoro citrus fertilizer.

I would assume that horse $hit would work as well...

Theoretically, horse manure should work several times better than cow manure. Cows have more complex stomach than horses as well as the microbial fauna inside which will extract more nutrients and utilize them. So what comes out of the cow is mostly undigestible lignin with very very few nutrients on it, unlike what's coming from horses. That is also why cow poops are very good to use as stove fuel in some places of the world. It burns very cleanly.

I have used horse manure in the distant past. I stopped because of weeds introduced with the manure. Horses that graze in open pastures end up eating a lot of weeds. You will find the weeds showing up in your garden. I am sure the same applies to cows that graze in pastures that have weeds. I have heard that manure from dairy cows works best because there are fewer weed seeds.

I use the composted cow manure that Lazz mentioned, except that I get mine at Lowes. I first started using it after a friend left some potted plants at our nursery. They grew so well that I asked what kind of fertilizer she was using. Answer: Composted cow manure from HD. I recently started using it in combination with my regular fertilizer, and, so far, it seems to help.

Joe, when I was younger I worked with Monfort which is an EXTREMELY LARGE cattle feed lot, in Colorado (in the top 4 largest in the nation). Cattle really do not digest as much of the feed as you think. It was a normal practice to mix manure into the batch of new feed and than feed ithat mixture back to the cattle. This was done because the once used feed (in other words MANURE) still contained 20 percent of the original feed nutrient value. Actually, I believe the feed value of the manure was higher but it has been too many years since I was at the feed lot to remember. Sounds gross but it is very common and saves the feedlots a ton of money on the feed bill. - Millet

That is why horse manure needed to be composted too. The high temperature of the composting process should kill off most of weed seeds and most pathogens. If you just left out the manure in a regular pile to compost naturally and then collect after several years, only the very core of that pile is composted, the surface may also have collected billions of weed seeds deposited by wind aside from the undigested seeds. In fact some of the seeds will need to be eaten by some animals before they will germinate, but most of these seeds were not designed to survive proper composting.

Based on personal experiences, if I buy composted manure from the stores, I find that composted horse manure are better than those of cow manure, but of course this could depend on the composting process.

On the other hand, for people hauling away raw manure, and either using them directly or some sort of their own composting process, the cow manures significantly have better responses from their gardens which I think you already know very well as you have indicated.

If you look here, and let me quote:
http://www.sturmsoft.com/Writing/guide_to-gardening/composts_and_fertilisers.htm

Quote:

Cow Manure This is rated second only to horse manure in value for the compost heap, though The Git rates it above all other manures. It is just as fibrous as horse manure, but is lower in nitrogen content. In the paddock, it retains much more of its nutrient content than horse manure. Biodynamic practitioners would not dream of making compost without it. Horse Manure Horse manure is very high in both fibre and nitrogen content as horses are very inefficient users of the nutrients in their food. A good source of horse manure is from racing stables. As very high protein diets are fed to racehorses, the manure is also highest in nitrogen. The manure will in all likelihood come already mixed with fibre of some sort, generally sawdust, or wood shavings. Care must be taken to ensure it is not contaminated with wood preservatives, such as copper-chrome-arsenate. Horse manure is generally rated number one for market gardening.

And base on my old notes of nutrient analysis, which are really highly variable depending upon the composting process, such as addition of limes, controlling acidity and other composting processes, but from earlier studies that I come across horse manure indeed shows that it has more nutrient contents than do cow manure. For example, not only do Total Nitrogen is higher, but most importantly, Potassium, the next majore element that citruses needed is several times more abundant in horse manure than do cow manures, in fact it is 1,814% much more in composted horse manure than do cow manure.

Composted horse manure
Conductivity 8.54
Nitrogen (total) ppm 583.6
Phosphorus, ppm 64.8
Potassium, ppm 3476
Calcium, ppm 118
Magnesium, ppm 54.7


Composted cow manure
Conductivity 6.74
Nitrogen (total) ppm 421.5
Phosphorus, ppm 0.4
Potassium, ppm 191.7
Calcium, ppm 1521
Magnesium, ppm 309.4


Composted worm castings
Conductivity 5.29
Nitrogen (total) ppm 315.9
Phosphorus, ppm 90.5
Potassium, ppm 1751
Calcium, ppm 154.9
Magnesium, ppm 104.1


Of course, this depends where your horses and cows graze, what kind of feed supplements they eat, and the like.

One thing for sure, if you are buying from commercial sources, take a look at nutrient analysis, some companies balances the nutrients for quality control, and this makes our discussions of which type has more, very "mooooo"t.

So if you have both horses and cows, it might help to feed horse manure to cows. I don't know if there were studies in this area, I only had 6 units of animal husbandry in college, and somehow remember some of it after more than 30 years, and the some of it part could be dangerous.

woooot!
Then im doing pretty well with the worming thing....
They took a hit in the heat over the summer, but we got a pretty big harvest this spring.

I dont know if its a regional difference, but the only times ive bought BlackKow, is been SUPER sandy.

Manure is both a soil conditioner and a fertilizer. Because of its high content of soluble salts, it can also cause burning. Manure should never be applied fresh. Always compost it for 1 year or more. If your impatient, check your local supplier as someone will have some well-aged manure. Manures vary greatly in nutrient content. The age and the type of manure creates many variables. This makes it almost impossible to know how strong it is. As a rule, the older the manure, the less nutrient value, but even old manure makes a good soil conditioner for poor soils. Rabbit and poultry manure are about twice as rich as that of horses, cows and pigs. Sheep and goats sit somewhere between the two. It is hard to give accurate recommendations for application because even the same type of manure may vary a great deal. But I'll do it anyway. Generally, I use manure only in soil and in raised beds, NEVER EVER in containers. In soil beds that are at least 18 inches deep, and for ground use, I add no more than 1 inch of well composted manure (half that amount for chicken or rabbit manure). Blend it thoroughly into the existing soil to prevent hot spots. If the manure is made up of large clods, try to break it up prior to applying it. Ned, if you don't want to bother with composting and waiting, you can also make MANURE TEA, even with fresh manure, by simply infusing water with the manure. Fill a gunny sack with the horse manure or prepare an old bucket to hold the manure. Take a nail and hammer hundreds of holes in the bottom and sides. Set the sack or bucket full of manure into a large container of water for a few hours. Remove the manure bucket/sack and your tea is ready. The "tea" is primarily a source of nitrogen and can be absorbed through the leaf as well as the roots. As you might have guessed, it doesn't smell great. If it is flavor you want, try Lipton. - Millet

What is the difference between mulch -- which is bad for citrus and manure? Does it not also promote phytophora?

Actually, I have just been using the processed one sold at Lowes. As I said, in the past I have had too much trouble with weed seed in the "free" piles, and I don't have time or energy to fool with composting. Maybe if I had the proper equipment, but shoveling manure around in compost bins ain't my cup of tea!

I have often wondered about farmers spreading manure over their fields. Seems like they would be spreading a lot of weeds. Then again, I suppose they are pretty selective about what they spread.

Ned

Thanks
This is already much more information than I thought I would get without reading several books.
So, don’t use it in the raw state but let it mulch for one year, Expect seeds to be a problem, and it is difficult to determine how strong or how much of the stuff to use.
One thought comes to mind about the weeds so what do you think about this idea?
Preen has the same ingredient of Treflan so what if I mixed the manure with Preen and turned over for a period of say now until February when I would use it for the first time.
Do you think that this would take care of most of the seeds? They say that Preen/treflan is only good for three months.
It’s not about the cost of fertilizer but, it’s about getting a product that is better than fertilizer. The three weeds that I have trouble with are pig weed, rag weed and crabgrass. And I sure wouldn’t want to add any to the mix.
Karl

We use Treflan in the nursery rows, on our farm, It works very well on most all weed seeds except pig weed. It does not do a very good job against pig weed seed germination. Anyway,I would not mix the manure and chemical. I would spread the manure, and then spred the treflan. - Millet