**4.1 Weeds management**

The field control has to begin in the autumn before the new agricultural year begins. Weeds like quack grass and foxtail can be found in dry clay soil, indicating calcium deficits and compact soil. Mow the grasses and compost the cuttings into the soil to help with calcium deficits. Broadleaf weeds, like ragweed, indicate copper deficiencies problem, and a phosphate/potassium imbalance. The rate between phosphate and potassium should be 2/1 for row crops and 4/1 for grass crops. Succulent weeds increase soil water capacity, replenish carbonate ions while covering the ground to protect against soil erosion. Weeds role is to deposit nutrients and metabolites in the soil or rearrange the nutrients existing in the soil. There is plenty of information in the literature about weeds role and weeds usage as a soil indicator [47–49]. This information is important to design a fertilization plan, in order to balance the nutrients. Herbicides must be avoided as much as possible since weeds get resistant to synthetic inputs, plants get unhealthy while the microbial population will decrease. Brix index in plants leaf must be measured before foliar application and 2 h

after. After a few foliar applications, the crop will thrive and weeds will be attacked by insects and diseases, and not the established culture. As the nutrients are balanced, pH changes and weeds are under control.
