October 25, 2006 | General

30-Plus Years Of Composting Experience

BioCycle October 2006, Vol. 47, No. 10, p. 26
New Era Farm Service manufactures 100,000 tons per year of compost, custom blending it for growers and showing them how to optimize results for cost-effective success.
Ralph W. Jurgens

SINCE 1975, New Era Farm Service, Inc. (a California Corporation) has been supplying compost to agricultural farm lands. At New Era, we deal with the “below portion” of the soil as well as the top portion of the crops being grown. Our key to these “biologically influenced fertility systems is organic matter and its management.”
If we are going to make a compost product that is high in humus and beneficial organisms, we have to understand soils – not only their physical and chemical aspects, but their biological fertility. In the chain of life, in microbial ecology, microbes eat at the table first. They are at the beginning of the first part of the chain, and we want to make sure we take care of these microbes because they release nutrients for plants. A fertile soil is a chemical self-feeder. The more we can build soil fertility, the more we can increase organic matter and convert it to humus – and the better the soil will act as a chemical self-feeder.
Ideally, soils should be 25 percent water, 25 percent air, 45 percent mineral, and two to five percent organic matter. Then we have the living organisms, which should be at a level of at least one percent.
The key to microbial vitality is the air-moisture relationships. If there is too much air and not enough moisture, microbes will die due to a lack of moisture. And if there is too much moisture in relation to air, the microbes will die due to a lack of oxygen. I like to ask my growers what is the most important ingredient for proper microbial viability – organic matter (as food), heat (to keep warm), moisture (water intake) and last but not least, air. Then I ask them how long they can live without food, heat, too little or too much water, or without air. Without food, heat or water, they might live up to four days. With too much water, they could drown. And without air, they could only last several minutes (how long can you hold your breath). The point is that in all microbial systems, air is by far the most important ingredient.
We teach growers how to use organic matter, encouraging them to buy compost and use it in their system. But if we don’t make them aware of air-moisture relationships and management, then the job we ask them to do can fail. Paying close attention to water practices (over-watering pushes out oxygen) is absolutely critical in sustainable farming systems because it can regulate the survivability of the microorganisms.
The soil colloidal mineral (cation exchange) balance is also very important in its ability to regulate air flow and moisture management. A soil high in percent saturation of calcium 65 to 75 percent and with an optimum balance of 10 to 15 percent magnesium, 2 to 5 percent potassium, and 0.5 to 1.0 percent sodium, is usually a good candidate for optimum organic matter management and microbial viability. When the soil’s percent saturation of magnesium becomes greater than 15 to 20 percent and calcium is lower than 65 percent, the soil can seal and cut off oxygen supply, to both the soil microbes and plant, thus affecting crop quality and health. Compost applications alone may or may not work due to the sealing effect, but by adding a calcium source with compost, we can assure better flocculation and air flow, allowing compost and its microbial viability to work better and longer for optimum soil and crop health.
We specialize in custom blending of compost (whether it is animal manure or green waste) to meet the soil’s specific needs. It is hard for me to tell a grower to put ten tons of compost on his soil and it will take care of all his problems because it may or may not. It depends on the soil structure itself, and on the nutrient loading capacity of the crop to be grown. For example, perhaps the soil needs additional calcium to help hold its platelet-like structure apart, allowing for better air flow and water percolation or movement. Calcium plays a real key role in keeping the soil flocculated, allowing for better air flow and water percolation or movement.
It is important to understand the soil’s cation exchange capacity and the percentage cation ratio’s for optimum microbial performance.
Once the compost is done, based upon analytical data and we determine what the soil’s limitations are, we custom blend our compost for each grower, e.g. a 50:50 blend of compost and gypsum, or a mix of 75 percent compost and 25 percent limestone. If the soil needs additional potassium, is it cheaper to add potassium (sulfate of potash) to the compost or is it cheaper to add more compost to the soil structure? If the soil needs more phosphate, we look at the cost of phosphate versus the economics of adding phosphate from compost. A dry ton of our particular compost consists of approximately 25 pounds of nitrogen (N), 30 pounds of phosphorous (P2O5), 60 pounds of potassium (K2O) and 50 pounds of calcium (Ca). Therefore, by avoiding supplemental phosphate and potassium, calcium etc., the savings can add up when five tons/ acre of our compost is applied.
Everything we do is specifically blended for the field. We always want to look at the soil first. Testing is critical. We base everything on analytical data, soil testing, and tissue testing and water analysis. That information is compiled, and then we try to custom blend from there. We even look at biological assays and microbial reserves bacterial or fungal balance.
A typical scene in our area would show dairymen using raw manure at fairly high rates. What is wrong with this approach? There may be no problem during the growing season; however at the end of the growing season, there can be an uneven release of nitrogen, inhibiting the crop from maturing.
Cover crops can be an essential as part of a Biologically Influenced Fertility System, especially, when applying compost over the top of a cover crop, at rates of two or three tons, will have a tremendous positive effect, on your biological system.
We also have experimented over the years blending screened compost at very small rates with commercial fertilizer. I always was led to believe that blending commercial fertilizer with compost would kill the microorganisms. But the results showed otherwise.
We applied 500 pounds/acre of a fertilizer (15 percent each of N, P and K). Then on half the field, we added 500 pounds of screened dairy manure compost. It was our first indication that we could apply compost closer to the root and increase the efficiency of the commercial fertilizer. This practice does not build soil fertility but it does increase the efficiency of the chemical fertilizer being put on. What we learned is that the compost released the phosphate more efficiently.
What we are trying to do by using small amounts of compost is increase the microbial environment around the root zone, making sure those organisms around that root zone can pick up nutrients more efficiently. Therefore, the value of compost becomes greater in small amounts. This knowledge became a key to our compost marketing program. When we were trying to expand our market, the limitation is trucking. Most everyone says we can only haul our compost 50-100 miles to still make a profit. Our work with using precision applied rates of compost applications led us to experiment with in season applications as well. This approach enables us to transport our compost 400-500 miles as a biological inoculant in the middle of the growing season right around the root zone to enhance root growth – at a cost of about $15 to $20/acre – giving higher yields to growers.
Overall, however, the use of precision applied compost does not replace a good fertility program – it only can enhance one.
Over the years, New Era has developed a few guiding principles that we stress to our growers. Based on our experience, compost is a key element in transitioning farmers from conventional to biological methods, but growers also need to balance nutrients for optimum production. When one element is deficient, its absence affects uptake of other elements. For example, nitrogen is critical to growth of plants and living cells. But one of the most common problems is over-fertilization with nitrogen, which results in higher magnesium availability, but lowers uptake of potassium, calcium and other nutrients. The end result is rapid cell wall expansion, which leads to weak cell walls and crops that are susceptible to pest attack.
In a biological system, where we are introducing thousands of microbes by applying compost, air and moisture have to be present in the right quantities for the microbes to perform well. If soil is completely compacted or too wet or too dry, you can apply the best compost in the world and get disappointing results.
Our goal at New Era is to educate and equip the grower with a cost-effective fertility program which meets the needs of the current crop and improves the quality and productive capacity of his soil.
New Era Farm Service is currently retailing over 80,000-100,000 tons/year of dairy manure compost on California and Arizona agricultural soils.
Ralph Jurgens, is an agronomist and co-owner of New Era Farm Service, Inc. in Tulare, California.
IN LIGHT of the most recent food safety E coli outbreak, it is extremely important that as a compost manufacturer, we assure our customers that our compost meets the current USDA/FDA food safety standards.
E. coli is a member of the family Enterobacteriaceae, which includes many genera, including known pathogens such as Salmonella, Shigella, and Yersinia. E coli O157.H7 is a specific strain that can kill.
Fecal Coliform are bacteria that live in the digestive tract of warm blooded animals (humans, pets, farm animals and wildlife) and are excreted in the feces. Research has shown that during the thermophilic stage of the composting process, from 130°F-150°F, (ideal 140°F), three days at 130°F, can kill most all parasites, weed seeds, and disease-causing organisms. It is important to turn the compost piles frequently to ensure that all parts of the pile are exposed to these temperatures.
To achieve pathogen reduction and food safety issues, each windrow is closely monitored during the compost process. Every 150 feet is probed at a sample depth of, 6″, 12″, 18″, 24″, and 36″, in two week intervals, monitoring for moisture, temperature, oxygen, and carbon dioxide. Each windrow is then turned based on these levels, which help stimulate the aerobic microbes and assure pathogen safety.
Once a month, each batch is tested for nutrient content, C/N ratios, EPA 503 Heavy Metals, and a Food Safety Screen, which tests for Salmonella, Staphylococcus aureus, Fecal Coliform, and E coli O157:H7. These batches are not released until they are tested safe and meet USDA/FDA standards.
As the demand for composted animal manure increases, organic vegetable, and fruit producers will demand a safe, pathogen free product.

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