Wednesday, May 16th, 2012
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STREET ADDRESS Polk County Corner Gibson St and Ward St 60 Gibson Street Columbus, NC 28722 (828) 894-8218 Phone (828) 894-5693 Fax Map & Mailing Information Recent Tweets MT@FireAntInfo [more] is the starting point for all things fire ants #insects #garden #invasives #CESvalue #CoopExt 
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Composting Horse Manure Introduction In 1995 two Burke County horse trainers worked with me to build two composting facilities to handle the manure from their operations. These composters are built from pressure treated lumber on concrete pads, and are under roof to prevent rain water from over wetting the material during the composting process and the storage afterwards. State Water Quality Cost Share funds were used to reimburse 75% of the construction cost. After operating the composters, the first buildings I know of that were designed and built expressly for composting horse manure and shavings, for 3 years we have learned how to incorporate the similarities, and overcome the differences, between composting this material and poultry mortality, which was the germ for attempting this approach to the problem. We can now report that, while the process is not a cure all, and while it is certainly not for everyone, the process does work and work well. The remainder of this document is a handout that I gave to interested horse owners attending a field day and demonstration at one of the horse farms. Composting The basic composting process is the same for horse manure as for any other organic product. The principle difference is the uneven distribution of nitrogen compounds through the manure and the bedding material. During the initial ferment our goals are short term storage of the material and to build micro organism populations to effective levels. The first turning will more evenly mix the higher and lower nitrogen content materials and, in the presence of the higher micro organism populations we have now developed, carry on the composting process. Of course the more stirring action done during the first turning, the more evenly these compounds will be mixed, and the fewer identifiable "muffins" will remain in the finished product. The importance of this, more or less aesthetic characteristic, will depend on the end user. For your own use as a pasture fertilizer the presence of a few obviously composted but still identifiable muffins will be of no consequence. If your customer is a landscape contractor who intends to use the compost as a mulch, identifiable muffins may render the product unacceptable. The more complete the mixing at each turning, the fewer muffins will remain. In any event it is important to remember that the finished product will probably still be identifiable as shavings or sawdust based. The finished product will not look like rich, dark earth. Continuing the turning and composting process will, of course, eventually render the product unidentifiable in origin, but this will add to the time requirement and will impact the space requirements of your building. Practically speaking, after the second turning the composting process will have progressed to the point where the material is free of pathogenic organisms and objectional odors. At this point the nitrogen compounds will also have become stabilized, enhancing their utility as a fertilizer. A third heat in the storage bin will further stabilize the material, but will have little effect on it's usefulness as an on-farm fertilizer. While shavings and sawdust are both wood products with the same carbon to nitrogen ratio, the fineness of the sawdust will reduce the time requirement for completion of the process and alter the appearance of the finished product. Conversely, feeding grass hay, which is higher in fiber than alfalfa, will necessarily result in wasted hay being mixed with the bedding and will lengthen the time requirement. In the absence of more rigorous stirring this will result in some identifiable hay fibers in the finished product. Again this is more an aesthetic consideration and does not reduce the product's usefulness as an on-farm fertilizer as the heat produced in the process will destroy the ability of the grass and weed seeds to germinate. It has been our experience that stirring to the degree requiredto eliminate the presence of identifiable characteristics of origin, such as shavings and muffins, is not economically feasible. Our greenhouse and nursery customers are not overly concerned with this and, in the busy world of breeding and showing, the less time diverted to managing the manure pile, the better. On the time requirement for managing the process, it can vary significantly with the type of bedding and the degree of mixing you feel compelled to do. One of our operators uses a small Bobcat and lifts and moves each bin to the next to mix and stir. This takes a long time, about 6-8 hours per week. The other operator uses a tractor and bucket loader to pull the material out onto the apron and then pushes and lifts it back into the same bin. He reports that this technique gets the time requirement down to acceptable limits, a couple of hours every other week, without sacrificing his ability to mix in enough new oxygen to keep things going. Another factor which plays into the time required for composting to occur is the moisture content of the pile. We have found our material to be slightly on the dry side and have found it advantageous to add water via a garden hose initially and at several times in the process. A water hydrant at the building is therefore strongly recommended. At the same time it is important to guard against over irrigation as too much water actually slows the process. The material should feel damp to the touch but squeezing a handful tightly should not result in any moisture either dripping from the ball or forming on the surface. Remember that excess moisture will move downward through the stack which may result in the interior moisture level being too high although the upper portion of the stack appears to be within the proper limits. With some types of composting it is necessary to supplement the nitrogen via nitrogen fertilizer. We have not found this to be the case with horse manure. While the nitrogen content is lower in the daily pickings than in the weekly cleanout, probably due to the movement of urine down into the bedding, we have had no difficulty maintaining a temperature in the 160 to 180 degree range over a two to three week period. This would seem to indicate that all of the necessary components are present in sufficient quantities for normal composting to occur. Temperatures in this range, and for this duration, are more than adequate to kill fly eggs and the parthenogenic organisms. What we have in effect is a large, self fueled autoclave. Horse owners will also appreciate the fact that the finished product lacks the distinctive aroma which renders pastures receiving untreated manure unpalatable to grazing horses. We have noted that horses grazing pastures receiving the compost graze normally and do not attempt to restrict grazing to thestreaks receiving the thinnest application rates. Some have suggested that horses tend to select against forages with high concentrations of nitrates. We have not noticed this with compost fertilized pasture forages, due either to the slower release of nitrate ions from the composted material or its lower nitrogen content. Analysis by the NCDA Waste Analysis Laboratory indicates 6.1 pounds of nitrogen, 4.5 pounds of phosphate, and 10.8 pounds of potash per ton on a wet basis. Compared to the 40 pounds of nitrogen, 33 pounds of phosphate and 42 pounds of potash in a recently submitted sample of poultry waste, this lower nutrient content has some appeal. It is less likely to cause nitrogen related problems such as blossom end rot in a home garden situation, where rates are frequently over applied. It is also reassuring to those compelled to spread the waste on their own property in a time and state where there is considerable concern over the over application of animal wastes and the associated nutrient saturation problems. One of the strongest advantages to this type of system is it's all weather capability and large storage area. Stall cleanouts need not be rushed or delayed in order to avoid inclement weather. Concrete pads, graveled access roads and the roof covering allow manure to be deposited in virtually all types of weather. Should a bin need to be emptied in order to make room for new material, this building has a storage bin capable of storing up to three month's production. We are therefore freed from the pressure of spreading waste on summer dormant or excessively muddy winter pastures, and can wait for conditions to improve. For those seeking EQIP or SWQ Cost Share funding there are restrictions which must be accepted. The site must be 150 feet from any well and 300 feet from any dwelling occupied by persons outside the owner/operator's family. In addition the recipient of grant money must agree to use the facility for a minimum of ten years. It has been our experience that the ten year use requirement is not a problem. The system is such an improvement over any other known system that not taking advantage of it's availability is unthinkable. There may be other local restrictions and it would be wise to check carefully for these before committing resources to construction. Should your operation fail to qualify for cost share assistance you should still be able to receive technical assistance from your local Soil and Water Conservation District and Extension Service. Please be aware that this is a new application of composting technology and not all SWC or CES personnel are going to be familiar with all the particulars. In such a case patience and perseverance are valuable attributes. |