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HISTORY OF VERMICOMPOSTING
Vermicomposting, as an industrial process, was originally developed to remove unwanted organic materials from the agricultural and industrial waste streams. The derived product: earthworm castings, is now recognized as a high value material which, when blended with soil, can restore soil tilth by correcting the imbalances caused by the over-utilization of petrol-chemical based fertilizers; thus enabling crops and plants to naturally combat pests and diseases, all resulting in increased crop production and general plant health. Using European technology we began researching production processes and the potential of Vermicomposting over 20 years ago. In 1991 we built the first American flow through Vermicomposting processor in Portland Oregon which continues to handle more than 2,000 tons of food waste per year at an annual cost savings of approximately $70,000.00. The Worm Castings are sold as an Organic soil amendment or mixed to form valuable plant growth media, as well as providing a natural pesticide and fungicide. In 1997: Awarded our first of three Phase I, and Phase II USDA-SBIR grants enabling advanced engineering, design and process modifications to be made in order to achieve a greater understanding of the production process and the products potential. In collaboration with Ohio State University, and Professor Clive Edwards, these grants supported extensive field and greenhouse trials using Vermicompost on a wide range of fruits, vegetables and ornamentals. The results clearly demonstrated that the affects were nutritional - as all experimental plants received the same full range of nutrients – and remarkably small quantities of Vermicompost promoted enhanced germination, growth, flowering and yield on a variety of crop plants. Agricultural wastes, food and garden wastes, paper waste, and bio-solids from waste water treatment plants, when processed by earthworms, all showed similar results. With the aid of two additional USDA-SBIR grants - again collaborating with OSU and Dr. C. Edwards - we investigated a range of structural and functional comparisons between Vermicompost and traditional types of compost. * The continuous-flow production process does not allow nutrient leaching as occurs with conventional thermophilic composting and some less efficient methods of Vermicomposting * There were large physical, chemical and biological differences, all seemingly related to leachate control and the organic waste passage through the earthworms gut. * Vermicomposting was far more efficient in controlling odors and other vector issues. * With high worm populations and optimum conditions Vermicomposting is much faster than most conventional composting processes. * The percentages of Nitrogen, Potassium, Potash, Magnesium, and Calcium - in forms readily available for plant uptake - are much greater in Vermicomposts. * Microbial activity is much greater in finished Vermicompost; maintaining many types of bacteria and fungi that contribute to soil health and fertility. Our research showed - in laboratory, greenhouse and field trials - that a specific amount of Vermicompost, added to commercial potting mediums suppressed diseases, insect populations and insect damage to and on plants grown in Vermicompost treated soils. It is now widely accepted that the readily available micro organisms available in Vermicompost are the likely source of the plant growth regulators and Humates now known to be responsible for the increased germination, flowering and yields found in the plant growth trials. The project then focused on investigating the reason why the smaller particle size and greater moisture holding capacity in Vermicompost contributed to a decrease in soil nutrient leaching when Vermicompost was added to soils; demonstrating the destruction of viable weed seeds through Vermicomposting and the destruction of humane pathogens in contaminated organic...
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