Growers can lend a helping hand to soil life in favor of the crop. With the combination of crop plan, green manures, soil tillage and control on a C: N ratio, they have various control options. During the online Soil Day of the Rusthoeve experimental farm in Colijnsplaat, experts discussed this with the growers.
According to Delphy’s consultant Pierre Cammaert, it is often better for the living soil to be left alone. “Non-inverting tillage keeps soil life more intact and in balance. It’s an argument for NKG. ” According to Cammaert, green manures are a good stimulus and protection for soil life in the period when there is no crop in the field.
Lein de Visser of CZAV discussed the influence of a diverse mixture of green manures. This makes it possible to create more diversity in the soil. De Visser states that steering on the ratio C: N is a steering option. The C: N quotient differs per green manure and thus the underground flora and fauna that live on it. There are more ways to control the C: N ratio. Growers can work with fertilizers, crop residues and soil improvers to stimulate beneficial soil fungi or bacteria.
“For bacteria, the C: N ratio of 10 is best and for soil fungi it is more between 20 and 25,” says De Visser. “In the short growing season, as a grower, you are more likely to have a beneficial effect on the bacteria than on the beneficial soil fungi. Instead of that bacterial dominance, we prefer to see more fungi. ”
Eelco Boot, manager of the experimental farm, points out the unfavorable effect of raw straw residues. A more active soil life breaks down the organic residues in the soil better and thus ensures fine humus and a beautiful structure. The company in Colijnsplaat is conducting research into soil improvers that focus on a better balance between the different types of soil life. According to Dennis Smits of CZAV, a smooth digestion of organic material is an indicator of an active and healthy soil life. With Neosol, the grower stimulates fungi in particular, with Soilset the soil bacteria and with a compost dose the grower actively contributes to organic matter build-up. Green manures contribute to soil life, structure and organic matter, according to Smits.
Harmful technique
The growers are allowed to participate in the discussion on the basis of statements. One of the propositions is that without adjustments to the (too heavy) machinery it makes little sense to work on better soil life. According to De Visser, it is certain that heavy machines have a negative effect on soil life. “I am convinced that it always makes sense to work on your soil life.” To reduce damage caused by heavy machines, Cammaert advocates adjustments to construction plans and a timely harvest time.
It is difficult for soil life to remove all damage caused by machines that are too heavy. When repairing compaction, De Visser thinks of the combination of rooting, soil life and mechanization: “You could first use a building advisor, followed by the sowing of a green manure. Its roots grow in the corridors made by the construction adviser and stabilize them. There is then a role for the soil life, but that alone will not make it. ” Cammaert states that, in the absence of real winters, NKG in combination with green manures works well. “Make sure that you have the drainage of the plot in order. That is important to me and of course it always is, even without NKG. ”
