Fall is almost upon us and we will be applying compost (thermophilic and vermicompost) to as many trees as possible. Presently, we have 4 windrows that are ready to be spread in the orchard as soon as they pass all the necessary tests (al 4 windrows probably weigh100-200 tons; precise measurements have not yet been made). They have the right amount of moisture, they have reached temperatures of 130F or more and were turned 5 times each time 130F was reached. They have been made predominantly fungal because of the proportion of woody/cardboard material used in their construction. They have undergone composting for 2-3 months and presently they are cooling down. Once the temperature of the windrows drops to 110 F or less, a biological assessment will be done to see if the compost is fungal dominated and whether it contains the necessary microbes in the right amounts. A chemical test will measure the evolution of carbon-dioxide and ammonia in order to confirm the biological results.
As part of the compost management program at Frog Hollow, we do a visual test and a smell test of materials that come from outside the farm (from local landscape businesses and horse stables). If some material does not look good or smells bad (anaerobic smell), it is not added to the windrows. We try to bio-re-mediate this material if possible.
We are preparing vermicompost for vegetable crops to be planted sometime in October. The challenge is to produce vermicompost that is as free as possible of weed seeds (which can compete with the vegetables). Thermophilic compost is theoretically free of weed seeds because it attains temperatures of 130F during its life cycle. However, our thermophilic compost is usually fungal dominant because we use it in the tree orchard. Also, thermophilic compost is not as rich as vermicompost in various plant nutrients including phytohormones. We are using coffee grounds to feed our worms instead of plant material and horse-bedding and the vermicompost should be almost free of any weed seeds. We will also be experimenting with making judicious mixtures of thermophilic compost and vermicompost (because we have less vermicompost than thermophilic compost). Finally, we will also use a bacterially dominant compost tea to make the thremophilic compost less fungal.
Author: Christophe Kreis MLF Soil Consulting PhD, Molecular Biology/Developmental Biology, University of British Columbia, Canada. Christophe is co-founder of MLF Soil Consulting with his wife Monique. He started his career in basic medical research and after various positions in academia and industry Christophe slowly returned to his first passion Soil Ecology and Microbiology. It is his belief that human health is tied intimately to soil health through the production of healthy food. For this reason MLF Soil Consulting is committed to help farmers improve the management of their soil through composting, vermicomposting and biological analysis of microbial soil life.