What are SOILTEQ philosophy’s basic steps?
Agriculture comprises a complex system of interacting processes. As Archambeaud noted, "...when we place soil and its fertility at the center of our activities, we ascertain that positive changes are reflected in the other system parts: climate change, pollution, water quality, soil erosion, etc." To help us work appropriately with soil and hence the whole system, it is important to follow the basic SOILTEQ philosophy steps.
Reorganization of soil structure
Many years of heavy ploughing and tillage lead to a horizontal structure of the soil with distinct compacted layers. A natural, vertical soil structure has to be restored in order to allow good water infiltration, roots growth and nutrients cycles. Reorganization of soil structure must be done mainly by cover crops: they replace metal by roots and fuel by photosynthesis while adding organic matter to the soil. Taking care of the soil structure is an everyday and long-term mission.
It is important to avoid farming operations in wet conditions as much as possible and consider minimum equipment weight to reduce compaction.
Creating permanent soil coverage
Soil must be covered by plants as much as possible. Every single day with bare soil means water evaporation, erosion, biological life destruction and time for weeds to develop.
- Sow cover crops right after harvest in order to take advantage of remaining moisture in soil and the long and warm days of summer for plant growth ;
- Care about cover crops sowing quality as if they were main crops. Cover crops are investments for the future. Only well managed investments bring good results.
- Mix at least 4 crop species in the mixture. Each of them have their own characteristics that will provide maximum soil coverage, roots exploration and biomass production. Diversity also allows for compensation in case of extreme weather conditions.
- Include at least 50% of legumes in the mix. Legumes have the ability to fix nitrogen from the air into the soil and make it available for the next crops. They bring a very high fertility value to the cover crop mix.
- Cover crop should be finished when flowering. At this point plants are the most vulnerable and can be killed easily by rolling, shallow tillage or frost (depending on the species).
Involvement of mechanization
Setting up SOILTEQ technology on farm does not require any specific equipment. Many farmers practice adaptation of existing machinery to improve quality of operations and evaluate which technics best fit their context. With time and growing expertise, farmers may invest in some specific machinery in order to improve their results and scale up their capacities.
Use intercropping in crop rotation selection, weed control and management
To select crops, it is necessary to know their advantages and disadvantages.
- Undersowing crops are sown at the same time or shortly after the main crop, and the herbicide strategy is adapted to the main crop’s treatment.
- Short period cover crops are sown as soon as possible after the main crop’s harvest to create maximum biomass and reduce weed competition. By producing high-quality green mass, we ensure nitrogen and simple sugars supply to support soil organisms and the nutritional intake of the subsequent crop (supports decomposition of post-harvest residues and supplies starting nutrients).
- Medium period cover crops are used before early-sown spring crops to protect the soil, so more species in mixtures can be afforded. They are more flexible in composition and date of sowing. They produce enough carbon for soil protection and creation of high-quality organic matter. Using more species ensures diversity in the root and above-ground mass. The target is to let the crop freeze and as soon as the cover crop grows, we roll it.
- Long period cover crops are used before later sown spring crops, such as corn, sunflower, and soya (also suitable for strip-till technology). Such create biomass and long-term soil cover. Spring and winter intercropping can be combined with subsequent spring desiccation. The target is to create enough biomass and soil cover from autumn to spring - simple as well as multiple-component mixtures can be used.
Cover crops need to be taken into consideration in the selection and term of main crop herbicide treatment, as intercropping creates good competition against the spread of weeds in the period between main crops.
Low-deep tillage and direct sowing methods reduce soil supply of weed seeds and regrowth, and allow you to gradually reduce the volume of herbicides for undersowing crops, as weeds are sufficiently suppressed by undersowing crops.
Strategy of fertilization
High-quality fertilization aims to maintain soil nutrients in a form acceptable for plants in order to prevent losses of nitrogen and other nutrients, e.g. by wash-out.
- Over half of the nitrogen that a plant receives comes from organic soil matter - not from supplied fertilizers.
- Content of organic matter in soil supports the regular supply of crop residues and supports microbial activity.
- Nutrition of micro-organisms and mineralization can be supported by plant roots (leading to correction of soil structure and aeration), spreading post-harvest residues, or using green manure.
- The correct nitrogen and phosphorus ratio that plants use is 2:1 to 4:1 – this is ensured mainly by the micro-organisms and plants that can bind nitrogen from the air.
- Livestock manure can be partly replaced by granular fertilizers containing hen or pig manure.
- When switching to direct sowing technology, it’s necessary to temporarily increase the dose of nitrogen fertilizers, due to the increased consumption of micro-organisms and limited mineralization. This investment returns in the next years.