• We had a fair amount of rain last week and this means that it was not possible to turn the thermophilic compost windrows as scheduled. It was difficult at times to measure the temperatures because of the muddy condition of the soil around the windrows, which was due to the fact that the local landscapers/arborists had to bring their woody material to Frog Hollow in spite of the rain. One of our windrows, which was constructed on August 27, has an average temperature of 117 F (28 readings) but still has about 5 hotspots ranging from 130 F-140 F. It looks like this will continue composting for four months and maybe beyond. As we discussed before, this windrow must have been constructed with a nitrogen rich material that was added in excess. The biology is being analyzed in this windrow and a chemical analysis is also being performed. Another windrow, which was constructed on September 19, will probably be ready before the end of the year for spreading (about three months of composting): the average temperature of this windrow is 117 F with only two hotspots at 130 F. Another three windrows that were started in October (10-14 October) look like they will be ready for application in early January.
• The outdoor vermicompost beds did not get too wet after the rains. The moisture in the beds has remained at the right levels. The worms did not leave the beds in spite of the high rainfall. In the indoor beds, I am using some of the beds to produce worms that are fatter. Some of the beds are used to increase worm breeding rates by the addition of oatmeal discards from the Frog Hollow Café (Ferry Building in San Francisco).
• When I discuss composting or the nature of soil organic matter or soil organic carbon or humus with people on the farm and off the farm, I realize that a lot of misconceptions concerning these terms are due to the fact that a lot of the products that are sold to farmers and gardeners are not defined properly by the manufacturers. I have discussed humus and soil organic matter briefly in previous blogs but I will start this discussion again but in more detail in subsequent blogs. Because of the enormous amount of carbon stored in soil organic matter, soil management and composting play not only an important role in agroecology but may be important factors in affecting/moderating the global greenhouse effect.
• What is soil organic matter? SOM is composed of all the living organisms that reside in soil (the soil foodweb) including the living roots of plants, dead tissue (remnants of microbes, roots, leaves etc.), and non-living non-tissue (humus and non-humic substances). Let’s reflect upon this definition and we will continue this discussion in the next blog.
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.