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I'm all in with organic gardening. That's all I use for all my needs, lawn flowers vegetables etc. I use no pesticides either. I'm looking for some links to support why synthetic, petroleum based urea is bad for soil. Can anyone help me out?

Thanks

Here is the link but you can read some of the effects below. Hope this helps.
https://www.sustainablebabysteps.com/effects-of-chemical-fertilizers.html


Negative Effects of Chemical Fertilizers

The biggest issue facing the use of chemical fertilizers is groundwater contamination. Nitorgen fertilizers break down into nitrates and travel easily through the soil. Because it is water-soluble and can remain in groundwater for decades, the addition of more nitrogen over the years has an accumulative effect.

At the University of Wisconsin, Madison, they discovered the effects of chemical fertilizers are compounded when mixed with a single pesticide. They discovered altered immune, endocrine and nervous system functions in mice, as well as influence on childen's and fetus's developing neurological, endocrine and immune systems. These influences "portend change in ability to learn and in patterns of aggression."73

One popular fertilizer, urea, produces ammonia emanation, contributes to acid rain, groundwater contamination and ozone depletion due to release of nitrous oxide by denitrification process. With it's increased use and projections of future use, this problem may increase several fold in the coming decades.105

Groundwater contamination has been linked to gastric cancer, goitre, birth malformations, and hypertension107; testicular cancer108 and stomach cancer.109

One of the big objections is actually the damage caused to the environment by the production of fertilizer from fossil fuels. The second is that synthetics are pure substances lacking any of the trace minerals etc that natural might have. Over time studies have shown that synthetic fertilizers tend to "wear the ground out". There are many of these small farms across this country that need a lot of rehabilitation to grow much of anything anymore.
This is the basic arguement in the nutshell.

Thanks guys!

Interesting article. I have just started my garden and initial use was DAP (Diammoniam phosphate), also intended to use urea but I think I will now ban it from my garden. Question remains what to do with the bought urea fertilizer. I will research further about disadvantages of chemical fertilizers and I think I will from now on stick to organic manures.

All fertilizer from what ever source has the potential to become a pollutant if it is used in excess or not applied in a way that protects surface and groundwater sources,.

It is not the use but the abuse that causes the problem.

Some organic contamination is a by product of the way agriculture is managed especially in dairy,cattle, chicken, and swine production where animals are kept in close quarters and high nitrogen waste is not managed well.

Synthetic fertilizers like urea can come from natural (animal) and man made sources. Some synthetic fertilizers take a lot of energy and can be polluting in the process of being made. However, this is not the case with urea.

https://www.fao.org/docrep/w2598e/w2598e06.htm#organic fertilizers
https://www.extension.umn.edu/distributi ... c0636.html
https://www.uvm.edu/~vlrs/Agriculture/or ... lution.pdf

Hi here is a great documentary about Dirt and how we are harming it and ourselves. They also talk about synthetic pesticides and fertilizers.

https://www.truththeory.org/dirt-the-movie/

It is a very good video. It is more of a comment of how far we as a society have drifted from our roots. If we nurture the land it will nurture us.

imafan26 wrote:Synthetic fertilizers like urea can come from natural (animal) and man made sources. Some synthetic fertilizers take a lot of energy and can be polluting in the process of being made. However, this is not the case with urea.

https://www.fao.org/docrep/w2598e/w2598e06.htm#organic fertilizers
https://www.extension.umn.edu/distributi ... c0636.html
https://www.uvm.edu/~vlrs/Agriculture/or ... lution.pdf

I looked at all three linked articles/sources. In two of them, the word "urea" didn't even appear. In none of them were the economics, whether financial or energy, of manufacturing urea analyzed.

In light of your lead-in ("Some synthetic fertilizers take a lot of energy and can be polluting..this is not the case with urea"), do you have sources to show this particular aspect?

Thank you.

Cynthia H.
Sunset Zone 17, USDA Zone 9

Hi Cynthia
Urea can be produced in at least two ways
Synthetically using the Haber-Bosch process which takes nitrogen from the air, uses natural gas (1-2% of the supply) to provide heat and the by-product is steam. This process was an improvement on other methods of creating nitrate.

https://en.wikipedia.org/wiki/Haber_process

The second source of urea is in manures. It is in the form of animal urine that can be mixed with bedding or fecal matter.
This is not a pure source and does contain other nutrients as well as contaminants and salts. Fresh manures are also a source of pathogens.

Another source of nitrogen (not urea) is from nitrates which can be manufactured or mined.

Spreading fresh manure on the land either by animal dropping or putting fresh manure on the land in quantity can cause contamination and runoff problems especially when it rains or when contaminated soil gets into streams and water ways.

That is why it is important that manures be composted first. It is also how fresh manure can burn plants.

Urea breaks down

CO(NH2)2 + H2O + urinase ==>2NH3 +CO2

I am rusty on my chemistry but the short end of this is that urea + water breaks down to ammonia and carbon dioxide.

Urea breaks down quickly and is readily absorbed by plants. It can also be lost quickly and must be incorporated into the soil or dissolved in water or it will volatize off back into the air as ammonia gas.

It is the same ammonia smell you get from compost piles that have too many greens that are breaking down faster than they can be incorporated.
And one of the strongest smells on chicken farms especially after rain.

Urea is an incomplete fertilizer. It does not contain any other nutrient, but if your soil test says you only need nitrogen. It is a good source since the nitrogen percentage is known and consistent.

P.S., most soil tests will recommend some nitrogen, even if all the other elements are high. Soil tests will tell you how much to apply to avoid waste.

Nitrogen applications should be divided and not applied all at once.

You could also use blood meal or other organically approved nitrogen source. It has a much lower total nitrogen and you would have to use a lot more of it at a higher cost.

https://d.yimg.com/kq/groups/24783254/18 ... 717891.pdf

Organic fertilizers need to be applied in larger quantities, and have other benefits including additional nutrients and biomass. They can also come with unwanted salts and possible pathogens. If your soil already has very high levels of phosphorus and potassium, it may be hard to find an organic source to provide enough nitrogen without increasing phos or potassium as well.

Synthetic fertilizers can be manufactured or mined. The process can be destructive and polluting.

What do the plants care about?

Synthetic nutrients are in their elemental form and readily available to plants. Applied in the proper amounts and at the right time, they are cheap and should not cause excess runoff.

Applied in quantity and without precautions to prevent runoff, it wastes money applying fertilizer you do not need and can run off into waterways damaging the environment.

Organic fertilizers are low in NPK, they require larger quantities to be applied to equal similar NPK of synthetic fertilizers.

For the plants to obtain the nutrients in organic fertilizers, they first need to be broken down into their inorganic form by soil microorganisms or fixed by nitrogen fixing bacteria from the air. This takes time. up to 6 months to complete, so all of the NPK in the organic fertilizer is released slowly over time, which is good thing. You want nutrients to be released slowly over time, but is not a quick fix.

NPK of organic fertilizers will vary much more than synthetics, depending on the source and in the case of manures, what type of animal and what they are being fed.

Organic sources can still have pathogens, antibiotics, wormers, pesticide residues that you may not know about. This is true especially if you are getting organic products from composting facilities, stables, chicken farms and tree trimmers.

https://www.extension.org/pages/18567/ma ... ic-farming

You do not know what is in the feed materials and how much remains after it is composted unless you specifically test for it. Although, proper composting procedures should limit these risks.

You can choose to use synthetic or organic sources of urea or any other nutrients. Plants can only take up nutrients in their converted inorganic (mineralized) forms.

If you are strictly organic, urea is on the prohibited list of source materials.

https://www.aasl.psu.edu/using_organic_n ... oruces.pdf

However, there are studies that favor urine, which contains urea, as a fertilizer.

https://d.yimg.com/kq/groups/24783254/18 ... 717891.pdf

To say that something is good or bad, you need to look at the source and their biases. If you are looking at University based research it is more objective (although it can still be biased) than from an organization with an agenda.

Either source can be polluting if not properly used. Both will provide what the plants need, if applied in the proper amounts at the right time.

The choice is yours.

The use of any synthetic fertilizer in an Organic Garden will absolutely destroy the whole purpose of the organic gardening in the first place. Synthetic Chemicals, Urea included will kill the micro life in the soil that actually break down the organic matter in the soil that in turn provide nutrients to your plants.

In a true organic setting with high quality organic soil your plants will grow healthier and arguably just as large as any synthetic fertilizer can even synthetic hydroponic setups. One of the main keys to ensure the quick growth like hydroponics provides is to make sure you mix a quality humate soil condition in your organic soil.

But the second you add a synthetic fertilizer to the organic setting described above the plant that received the synthetic fertilizers growth will slow possibly begin to burn the plant or even kill it depending on how sensitive the type of plant your are growing is.

I believe in the middle ground. I do not get great yields using organic fertilizers alone. The plants and soils are definitely healthier with the addition of organic matter, but I get bigger plants and higher yields with the addition of synthetic nitrogen.

To prevent the harmful effects that are attributed to synthetic fertilizers, I do get soil tests and apply only what is needed in divided applications. My soil tests indicate that only nitrogen is needed as there is more than adequate amounts of the other elements.

I do not use manures because of the risk of pathogens and even manures can cause harmful runoff.

I have a small garden, a 365 day growing year, and I would have to plant a green manure or wait about 6-8 weeks to plant my garden after applying manures and organic matter.

I do not have a traditional compost pile. I do not have the space for a large pile. I use vermicast and incorporate crop residues, kitchen waste and add purchased compost. Since I do not use animal products in my garden (except for vermicast), it is difficult for me to get enough nitrogen through organic matter alone.

Synthetic nitrogen does not kill off all soil bacteria, on the contrary, some bacteria actually thrive in a nitrogen rich environment. Soils rich in organic matter will tie up nitrogen making less available to plants until the organic matter breaks down and the bacteria die.

Nitrogen should not be applied directly to the seed. It will burn.
It should be incorporated into the soil as soon as possible so less will volatize off. Nitrogen should be applied in divided doses at the right time that the plants need it.

Organic or inorganic fertilizers can be sequestered in soil organisms as they consume the nitrogen and make it temporarily unavailable to plants until the the bacteria die and release the nitrogen they have stored. Most nitrogen is tied up in organic matter.

"Immobilization is the process of incorporating inorganic into organic form by microbes or plants. Because it is largely dependent on microbes, the availability of carbon and other nutrients determine the rate of immobilization. When residues with high carbon:N ratios are being decomposed, all readily available N within the soil system may be tied up by the microbes and therefore unavailable for plant uptake. This effect eventually fades because, without external N, the microbial population dies off and decomposes, releasing N which is available to plants. The risk of immobilization is avoided by mixing plant residues into the soil well before the next cropping cycle."

"Organic matter, which contains the majority of native N, is concentrated in the plow layer of soils, and is thus susceptible to loss by erosion. Loss by erosion is reduced by soil conservation practices.

Leaching losses occur when NO3- remains in the soil water and moves away from root uptake areas with downward water movement. Nitrogen lost in this fashion is a contaminant if it reaches ground or surface waters. Leaching is more likely to occur when rainfall exceeds crop use. Prudent management options that lessen the probability of NO3- leaching include using recommended rates of fertilizer N for the crop being grown, using realistic yield goals in cropping decisions, applying N as close as possible to when the crop will need it, using winter cover crops to scavenge N left over from the previous summer and giving credit for all possible N inputs such as legumes or manure application."

Organic culture does increase soil microbial activity. The use of organic or synthetic fertilizers promote different microbial species.
Organically amended soils were higher in thermophillic bacteria, but contained twice as much enteric bacteria like e. coli than synthetically fertilized soils.

Organic culture can over time 3-5 years reap a benefit in higher yields. Organic alternatives contain more micro nutrients that are not usually added to synthetic fertilizers and they build soil which synthetic fertilizers do not.

Organic culture works. But, an investment must be made in planning a year ahead. Organic matter and organic fertilizers do not release their nutrients readily and the soil bacteria will compete with plants especially for nitrogen. Organic matter benefits successive crops, but until the organic matter is completely broken down, the soil microbes will compete with the plants especially for nitrogen.

https://projects.cals.ncsu.edu/ristaino/ ... rticle.pdf
https://msucares.com/crops/soils/nitrogen.html

If you want larger yields with organic gardening it's simple make sure to have a lot of worm castings and humate. Composting creates humate, organic fertilizers breaking down creates humate but not in enough of an amount to allow nutrients in your soil to be available enough like a synthetic fertilizer would. Another reason your you won't experience large yield with organic gardening in your sense is because of the synthetic fertilizers. Synthetic fertilizers which use EDTAs to chelate nutrients which makes them available to your plants but kills all the beneficial bacteria the EDTA comes in contact with so by adding the synthetic fertilizer your just killed all the living organisms in your soil that were feeding your plants.

This specific reason is why you use a high quality humate and use it in healthy amounts mixed with your soil. Humates provide humic and fulvic acids which organically and naturally make nutrients highly available to your plants. Organic Nitrogen fetilizers are needed through out the the growing season because you are feeding the microlife not the plants. The microlife need nitrogen to feed your roots and help ward off pests and diseases.

The synthetic fertilizers is why small yields using organic fertilizers even liquid organic fertilizers use synthetic forms of humic and fulvic acids. That's why use a high quality humate soil conditioner will provide higher yields in organic gardening and I mean hydroponic like yields.

imafan26 wrote:I believe in the middle ground. I do not get great yields using organic fertilizers alone. The plants and soils are definitely healthier with the addition of organic matter, but I get bigger plants and higher yields with the addition of synthetic nitrogen.

To prevent the harmful effects that are attributed to synthetic fertilizers, I do get soil tests and apply only what is needed in divided applications. My soil tests indicate that only nitrogen is needed as there is more than adequate amounts of the other elements.

I do not use manures because of the risk of pathogens and even manures can cause harmful runoff.

I have a small garden, a 365 day growing year, and I would have to plant a green manure or wait about 6-8 weeks to plant my garden after applying manures and organic matter.

I do not have a traditional compost pile. I do not have the space for a large pile. I use vermicast and incorporate crop residues, kitchen waste and add purchased compost. Since I do not use animal products in my garden (except for vermicast), it is difficult for me to get enough nitrogen through organic matter alone.

Synthetic nitrogen does not kill off all soil bacteria, on the contrary, some bacteria actually thrive in a nitrogen rich environment. Soils rich in organic matter will tie up nitrogen making less available to plants until the organic matter breaks down and the bacteria die.

Nitrogen should not be applied directly to the seed. It will burn.
It should be incorporated into the soil as soon as possible so less will volatize off. Nitrogen should be applied in divided doses at the right time that the plants need it.

Organic or inorganic fertilizers can be sequestered in soil organisms as they consume the nitrogen and make it temporarily unavailable to plants until the the bacteria die and release the nitrogen they have stored. Most nitrogen is tied up in organic matter.

"Immobilization is the process of incorporating inorganic into organic form by microbes or plants. Because it is largely dependent on microbes, the availability of carbon and other nutrients determine the rate of immobilization. When residues with high carbon:N ratios are being decomposed, all readily available N within the soil system may be tied up by the microbes and therefore unavailable for plant uptake. This effect eventually fades because, without external N, the microbial population dies off and decomposes, releasing N which is available to plants. The risk of immobilization is avoided by mixing plant residues into the soil well before the next cropping cycle."

"Organic matter, which contains the majority of native N, is concentrated in the plow layer of soils, and is thus susceptible to loss by erosion. Loss by erosion is reduced by soil conservation practices.

Leaching losses occur when NO3- remains in the soil water and moves away from root uptake areas with downward water movement. Nitrogen lost in this fashion is a contaminant if it reaches ground or surface waters. Leaching is more likely to occur when rainfall exceeds crop use. Prudent management options that lessen the probability of NO3- leaching include using recommended rates of fertilizer N for the crop being grown, using realistic yield goals in cropping decisions, applying N as close as possible to when the crop will need it, using winter cover crops to scavenge N left over from the previous summer and giving credit for all possible N inputs such as legumes or manure application."

Organic culture does increase soil microbial activity. The use of organic or synthetic fertilizers promote different microbial species.
Organically amended soils were higher in thermophillic bacteria, but contained twice as much enteric bacteria like e. coli than synthetically fertilized soils.

Organic culture can over time 3-5 years reap a benefit in higher yields. Organic alternatives contain more micro nutrients that are not usually added to synthetic fertilizers and they build soil which synthetic fertilizers do not.

Organic culture works. But, an investment must be made in planning a year ahead. Organic matter and organic fertilizers do not release their nutrients readily and the soil bacteria will compete with plants especially for nitrogen. Organic matter benefits successive crops, but until the organic matter is completely broken down, the soil microbes will compete with the plants especially for nitrogen.

https://projects.cals.ncsu.edu/ristaino/ ... rticle.pdf
https://msucares.com/crops/soils/nitrogen.html

One more thing using a soil that has had synthetic fertilizers in it with in a minimum of 4 years will also create lower yields because of the EDTAs that are still present in the soil killing the micro life as they try to populate the soil

You are correct. I do believe that it does take time for organic culture to show results and it does take 3-4 years to transition for improved yields.

I don't agree that synthetic fertilizers kill soil microbes. I think that there is a different biota in the soil from organic soils. The removal of organic matter and the continual plowing of conventional farming does not build soil and those practices are harmful to the soil web. There are still microbes living in the fields of conventional farms. They are just different species and fewer in total number.

If conventional farming practiced vertical or minimal tillage they would preserve more of the microbes in the soil web. If organic matter was added by incorporating more crop residues and adding composted or other organic materials, the soils would be able to support more soil microbes and more species and help repair the soil, even with the judicious use of synthetic fertilizers.

I have added humic acids in the form of gro power. I did like the result, but it is difficult to get here as there is not much demand for it. It is like butter, it has a relatively short shelf life....four months or the beneficial organisms in it will also start to decline in storage.

It is why I have been doing more vermicast and I looked into bokashi and EM1 to increase microbial activity.

I do not use manures or animal products because of the risk of pathogens. Heat treated chicken manure is relatively pathogen free but would also not contain any other beneficial microbes. Chicken manure would also increase the soil pH by 0.5% which is undesirable.

If you are determined to find something bad you probably will.