Then the soil will sit for 1 - 1 1/2 months before planting. I am now wondering if this is sufficient time for the raw manure to break down or if I will have to worry about E. Coli, Listeria, or Salmonella being passed to the future veggies. Please help!

*****

I don't know where this gardener lives and grows a garden b/c that would also impact the rate that pathogens in the manure would be inactivated, but I would not suggest doing what is proposed.

And above there were quite a few pathogens that were not included. It's just too risky.

There are any number of links one can find by Googling that give the US Ag depts recommendations about using raw manure and I picked just one of them to link to below.

Hope that helps.

Carolyn

Here is a link that might be useful: raw manure as compost/fertilizer

Wow, Harmonyliz, I'm not Dr. Carolyn but you reminded me of the way we once did things on the farm.

Our vegetable gardens were just outside the corrals. Each year, Dad would scrape the cow manure out and we would use of the previous year's pile of manure - spreading it and plowing it into the ground. One year, we used what bad been pulled out that Spring.

Everything went well until the garden began to dry and then we turned the water into it. The beautiful leafy greens that had been doing so well then looked like someone had gone thru them with a blow-torch. They were "incinerated." I don't recall what happened to the tomatoes.

Incidents of E. coli infection haven't just occurred as a result of growing food in a few California farm fields. People have been taken ill from eating backyard garden produce, as well.

Here's what Colorado State University has to say, "In home gardens, it's recommended that all manure be well composted before being added to soil where vegetables or fruit are growing. Bacteria will survive winter freezing so fall garden applications and even 'aged manure' additions provide no guarantee of a garden free of potential disease organisms." They recommend "hot composting" manure then allowing 2+ months additional time after the temperature has fallen before garden application.

I don't think that an abundance of caution is uncalled for in bringing animal manure and human food together. These infections can be life-threatening, particularly for children.

Steve

Here is a link that might be useful: Fresh Manure and Food Gardens Don't Mix

Well, there you have it . . .

Thanks so much for your comments!

Carolyn - I am in zone 7A. I had read about the time frames but have not seen the link you sent - thanks! I knew that it would be close, but it sounds like not all is lost. If the soil is going to sit for 1 1/2 months (March - mid April) with no animals on it, then I plant in late April, then I should be able to harvest many crops as long as they do not mature before the 90 (no soil contact) or 120 (with soil contact) days. I do plan on using drip irrigation and mulching around seedlings so this will help with the soil splashing. It sounds like I could start harvesting in May/June without worries. Am I interpreting this correctly?

Steve - I did see the article you included during my research and felt that as long as things heated up then it was relatively safe, although it does say that even 140 degrees can leave some pathogens behind. I don't think that the manure/bedding will get to this degree, but I was thinking about solarizing the area with clear plastic during March and April to heat it up for a long period of time. Do you have any thoughts on this?

Got to agree - using fresh manure (fresh being any that hasn't been well composted) in a produce garden just isn't recommended. The associated risks outweigh any benefits or convenience. Lawns, flower beds, etc. fine - use at your own risk. But per lots of studies available on the web - for vegetable gardens - compost it thoroughly before use.

Dave

"I am starting a new veggie garden and have used a box scrape to clear the grass away. What is left is clay soil that has never had any amendments."

There are varying degrees of "clay soil." Is the soil clay loam, sandy clay loam, or simply hardpan clay? What percentage of clay to sand and organic particles? Etc.

If indeed it is a poor, hard clay soil, then it needs to be amended with organic material and the organic material needs to be thoroughly blended in with the top 12" of soil into which the garden crops will be planted. The organic material will glom with the clay particles and provide a texture that allows water to perk down through the soil without chronic saturation as would be a problem with hard clay only.

"I wanted to increase the fertility before planting in the spring and I have access to cow manure."

Cow manure is a great source of oganic material especially when it's mixed with bedding material and thoroughly composted before being blended with the clay soil. Still, the emphasis is on blending the organic material with the existing soil so that the organic material is well incorporated into the soil texture to a depth of at least the top 12 inches of garden soil.

"My plan was to fence our 14 cows in the garden area for Dec. and Jan. and feed them hay so that they would concentrate their raw manure over the garden soil."

First of all, I don't know what the area of the garden is. You don't say how many square feet of area un which you intend to keep the cattle enclosed. SOunds like a bad idea to me though simply because the cattle will further compact the soil by trampling it with their hooves and their heavy bodies. This will not accomplish the task of stirring up the soil, encorporating the organic material with the clay, and developing a good tilth needed for a garden plot.

"I will layer wood chips, leaves, and mulch over the manure periodically during this time."

If the wood chips, leaves and mulch aren't thoroughly composted before being blended with the raw manure, all you're doing is extending the time required to compost the materials properly. All the chips, mulch, leaves, manure, etc., should be contained in a compost heap to develop the proper heat and micro-organisms needed to break down the raw material into composted organic material ready for incorporation into the garden soil by means other than hoof trampling.

"At the end of Jan. I plan on moving the cows out and moving the pigs in, who will root through the layers of manure and organic material to mix it up and aerate it."

Who says that pigs rooting through the accumulated manure and spoiled feed with "aerate" it? Pigs not only root, they wallow, urinate, deficate, and add more compaction and raw material that requires proper blending and composting to process it into usable material. BTW, pig manure is more concentrated than cow manure in that it has less "roughage" from bedding and feed sources. Bad bad idea.

"Then the soil will sit for 1 - 1 1/2 months before planting. I am now wondering if this is sufficient time for the raw manure to break down or if I will have to worry about E. Coli, Listeria, or Salmonella being passed to the future veggies."

No. Maybe if the manure and other waste materials were heaped into a compost pile, and the interior temperature reached the required 130*F plus temperatures required to "pasturize" the material, and you stirred the compost occasionally to incorporate oxygen and to move un-composted material from the outside of the heap to the interior "working zone," THEN you might be able to get a finished organic material suitable for gardening in a couple of months maybe.

Working compost at sub-85*F average daily temps by laying it flat on the ground even during warm weather, is a much slower process and usually leaves raw pathogens. And here you're talking about trying to accomplish grade-level composting in winter weather! Bad idea.

Additionally, preparing a new garden bed from unworked soil, especially hardpan clay, requires working up the bed at least one season ahead of planting. You may still have time to work up the garden if you mix say 5% - 10% organic material with the top 12 inches of soil, thoroughly incorporating the organic material with the native clay soil NOW.

To calculate how much FINISHED organic material to apply to the top 12 inches, measure the dimensions of your garden to get the square footage. In this case the square footage will equal the cubic feet because you are tilling one foot (12 inches) deep.

So, when you have the square footage, you can either acquire 5 - 10% of that figure in composted organic material in cubic feet, or you can calculate it in cubic yards by dividing by 27 (cubic feet per yard). Or you can calculate it in pounds by estimating that one cubic yard of compost equals about 1000 - 1400 pounds depending on moisture content.

Example: 100 feet x 100 feet garden area = 10,000 square feet.

10,000 square feet x 12 inches deep = 10,000 cubic feet.

10,000 cubic feet/27 = 370.37 cubic yards.

370.37 x 5% = 18.51 cubic yards.

18.5 cubic yards of composted organic material is going to be about 18,500 - 25,900 pounds or 9 - 13 tons of compost.

You'll get by with less than 5% organic material if your soil is clay loam. You might even get by with less than 5% organic material if you soil is hardpan clay. But I would want more myself ... more than maybe 10% even. JMO.

Harmonyliz,
I like the holistic approach you are describing and have read where your idea came from.

I come from the school of thought that has witnessed and believes that the hooves of the cattle naturally will work organic matter into the soil. They urine will increase the nitrogen and help break down the bedding you add.

I have heard and if I had the land resource us multiple paddock rotations where you place the livestock in one paddock, follow them with chickens to spread the manure, allow the land to fallow for a year with a cover crop, then cultivate a cash or veggie crop, followed by the livestock again.

In your case I think that the diet and of the cattle and the bedding used is most important for the quality of the organic matter produced. The swine will do alot of work for you too. I believe you will have alot of manure worms and soil life.

I think this a good conversation to have. For one thing, it points to the limited regulation on raw manure/sewage sludge application in US agriculture.

Harmonyliz, as Hoosiercherokee points out, you are using your garden area more as a Winter feedlot than as a composting site. Urine salts build up and may ultimately have a toxic effect on plants.

To return again to pathogen contamination, some studies have shown that E. coli O157:H7 can survive in a simple manure pile for 21 months. Even a "manure pile, which was periodically aerated by mixing, remained culture positive for 4 months."

A study of the survival of E.coli O157:H7 in soil after the application of manure was detectable for more than 109 days at 15C (59°F). That is warm soil.

In Canada, "Standards for organic production allow the use of manure that has been stacked and aged for at least six months unless it has been brought in from off the farm, in which case composting is required. Raw manure can also be used but only on perennials or crops not for human consumption. Raw and aged manure should be spread when the soil is warm enough (i.e., when plants are growing) for the micro-organisms to be active."

Steve

On this issue I agree that properly heat-composted stuff is the preferred thing. But, it is not free unless you have the resources to "make" it yourself... and even then it is not entirely "free". The stuff I get in the fall is mostly raw and even in a 4 or 5 ton heap, it will not develop much heat at all with low ambient temps. Stack a 25 ton pile, yes it will.

Deal here is that getting "free" and "well composted manure" usually does not happen. Nevertheless, were I Liz, I would try to collect and stack at least SOME it in a waste area close to the patch. More work but that would be a resource that could be applied after the plot was been worked in early spring.

Now on the example used to calculate amount of amendment to add (370.37 x 5% = 18.51 cubic yards...) it is not quite correct because it does not account for the volume of the amendment.

The real final vol concentration in above example is 18.51/(370.37 + 18.51), which is 4.76%.

Rewritten should be: 0.05(370.37 + [370.37*0.05]). This resolves to 19.44 cubic yards.

Reg

Personally, I would be worried about the run-off from the concentration of raw manure and urine and its possible contamination of the water and land because fencing in the animals in no way fences in the run-off.

I think talking with your local extension and grange representatives will be a wise and prudent thing to do before you undertake this auto-fertilization with your cows and pigs. They will set you straight as to its wisdom or folly and they can also advise you if the concentration is a red-flag for inspection.

http://managingwholes.com/-restoration-no-soil.htm

Wow! So many opinions on this topic, I had no idea. First of all, the area is 150 ft. X 100 ft. (probably not all to be planted in, but this is the area we are attempting to amend. Also, I would describe the soil as pretty heavy clay, but I am new to the region and this type of soil so I'm too sure of the differences between clay loam, etc. The soil cracks when dry, holds water like a sponge, and you can form balls when it is wet, so I would think there is a lot of clay there.
I did expect the animals to compact the soil and figured I would have to rent a subsoiler before planting. This will not only break up the compaction, but also work some of the manure/bedding into the top of the soil. We did put down a layer of dried corn first which will encourage the pigs to root deep through the manure/bedding layers to thoroughly mix it up. This is where the aerating comes in as pigs root a lot!

I do believe that the diet of the animals will be beneficial in this process. The cows eat hay, spilling some on the ground and adding to the organic matter (I agree weeds will be a problem no matter what). They are also all grass fed cows, who have little E. Coli compared to grain fed. The pigs do get supplemental grain with their hay, but this is contained in the feeder and will only enter the mix through their manure.

In regards to the "feedlot", maybe I can give a clearer picture by saying that containing the cows in this area for two months will probably result in about 1" of manure across the area and this will be layered periodically with mulch, leaves, etc. for a total depth of, oh, maybe 6". This is not like the cows that stand waist deep in manure. I think you are right though that this is not officially composting. My concern is exactly that - will it heat up enough, etc. Also, the study that you send refers to sheep manure, but it also states that, "An E. coli O157:H7-positive bovine manure pile was culture positive for 47 days." This makes me think that cow manure must break down faster than other types.

All-in-all, I am thinking that raking the manure into a pile on a frequent basis and adding the organic material just in that pile will result in a more traditional compost pile, which will heat up more and be able to be turned. Then, if it does not seem broken down enough by planting time I don't have to spread it out until it's ready. I will surely have to locate this pile on the low side of the area to avoid any run-off.

Thanks for all of your help!

The second study I cited above utilized cow manure-amended soil. E.coli was detectable in the soil for more than 109 days at 15°C (59°F). I garden in a different zone but my soil temperature would not even reach this temperature until Summer.

Regarding the amount of manure - - According to Purdue University, "Beef cows produce about 75 pounds of fresh manure per day." 75lbs x 14 cows x 60 days = 63000 lbs manure, or, 31.5 tons.

Using Purdue's calculations this amount is equal to 840 cubic feet of cow manure on your ground alone. This does not account for the pigs and the time they are on the land. (Nor does it count spilled hay or the "wood chips, leaves, and mulch" you said you would apply.)

We never had more than 40 head of cows but the corral was larger than your area altho' not double. The cows had access to pasture right thru the Winter and were only fed in the corrals. Manure would pile up in that area more than 3 feet deep by Spring.

Steve