The sowing and the subsequent burial or shredding of a crop that belongs to the Brassicaceae family (usually horseradish or mustard), and used especially where there are nematodes in the ground, but more generally to disinfect the telluric environment. The biocides freed by Brassicaceae used as green manure are extremely volatile with quite a short half-life, meaning that there are no derivative products or bioaccumulation. The plant’s biocide effect does not affect the action of the green manure in any way, i.e., to protect of the soil with plant cover between the main crop and the next crop and also to provide organic matter. The action is also quite fast and therefore can roughly act on bigger telluric community populations without creating a biological vacuum. This has a type of purifying effect, after which the land can be repopulated in a more balanced way by the surviving organisms. The most harmonious action is the one obtained through mixing the species, especially in the case of temporary or permanent grass planting of multiannual crops.