The last time we connected via this blog, we were discussing soil organic matter (SOM). This topic is very interesting and very dear to me. However, it is a complicated topic and at this time I realized that I am not conveying clearly to the general public the importance and complexity of this topic. My science is very good but my blogs on this topic lack clarity. For the time being, we will put aside SOM and return to it at a more opportune time.
We are focusing on spreading as much compost as possible because we have many windrows and we have too much wood chips. Most of the windrows have been composting for three months or less. We still have three windrows that were started in November and have only recently reached high temperatures. They are being monitored closely and I think they contained some substance that was difficult to decompose by the microbes in the compost foodweb. The high temperatures indicate that the microbes in the compost ecosystem have finally adapted to the compost conditions and are metabolizing the unknown compound that is causing problems. After the temperature of these windrows drops to acceptable levels, samples will be analyzed for the biology, the micro-nutrient content and a bioassay will be performed using beans or peas as the test vegetable (using the right controls we should be able to determine if the compost is good or bad).
An 89 foot windrow labeled N-6 is destined to be spread on the McKinney field (about 1 acre) where Marlene and Kristin will be planting peppers and tomatoes. This windrow was constructed so as to be dominated by bacteria (the ratio of bacteria to fungi should be higher than in the fungal dominated windrows). N-6 was started on 19 January and this week the temperatures in this windrow have dropped to acceptable levels. The windrow will be turned and watered one more time to make sure that the windrow is cooling. The windrow will be analyzed for the biology and for various nutrients. In the mean time, a bacterial tea is being applied to the McKinney field to speed up the rehabilitation of this field which last year did not perform very well (yields and health of various vegetables was not spectacular).
Farmer Al has been concentrating a lot of energy on applying compost tea to apricots and peaches due to the weather conditions (cool nights, warm days, a little bit of humidity). Two diseases (brown rot and mildew) are of major concern and we have been preparing compost tea with a fungal dominance (the beneficial fungi in the tea are there to outcompete/suppress the non-beneficial fungi).
More bacterial teas have been used to water the various seedlings that Marlene and Kristin are preparing for the McKinney field. The idea is to create a healthy soil foodweb in the seedling pots and to suppress any potential diseases.
The rates at which compost and compost tea are applied can be very different depending on the final outcome that is needed. Farmer Al has thousands of trees on 140 acres of land. He has to apply as much of his on-site produced compost as he can get his hands on and he can never have too much compost (we will do a calculation in a future blog to prove this point). Farmer Al also use compost tea to suppress diseases and he also can use as much tea as regulations permit (C.C.O.F.). The vegetable farmers are starting seedlings in pots that contain compost. I have recommended that the seedlings should only be watered 3 times with compost tea before they are planted in the McKinney field. The reason is that the compost and vermicompost should contain a healthy foodweb and watering with tea should be done just an initial enhancement of the biology. Too frequent watering in a closed environment (pots) is redundant and may cause problems. On the other hand, Jennifer (CSA coordinator) and Pearl (marketing director) have started their vegetable gardens and mini-orchards. Jennifer has a vegetable garden and a sandy soil. Her ecosystem needs as much compost and beneficial microbes as possible to create structure. Pearl has planted two fruit trees (Frog Hollow trees) in her back yard. Odds are that her soil needs remediation and can use in the short term as much compost and compost tea as is practical. Three different groups of people three different uses of compost.
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.